Skip to main content
Chemical and Biological Technologies in Agriculture
Download PDF
Download ePub

Effect of mechanochemically modified MoO3–ZnO on Mo supply to plants when co-granulated with macronutrient fertilizers

Chemical and Biological Technologies in Agriculture volume 11, Article number: 115 (2024) Cite this article

Abstract

Molybdenum (Mo) is an essential micronutrient required for plant growth but is prone to leaching from neutral and alkaline soils. The use of slow-release Mo sources could potentially reduce leaching losses from soils and increase crop yields. In this study, we assessed mechanochemistry as a green method to produce slow-release Mo sources. Molybdenum compounds (MoO3 or (NH4)6Mo7O24·4H2O) were mechanochemically (MC) treated with ZnO to synthesize compounds with a Mo content of 1–36%. Reduced Mo solubility after MC treatment, compared to the initial Mo source, was obtained with the MoO3 source and these composites were used for co-compaction with macronutrient fertilizers. Macronutrient pellets with 0.2% Mo were compacted using the 4% Mo and 36% Mo (characterized as ZnMoO4) compounds. A column dissolution test showed that the 4% Mo compound in a macronutrient carrier (DAP and MAP) only released around 40% of the total Mo compared to 80% for a non-MC treated control over 72 h. Column leaching using two soils revealed that the release behavior of Mo was strongly related to the pH of the leachate, which was affected by both the soil pH and the macronutrient carrier. More Mo was released when the MC-treated compound was co-compacted with diammonium phosphate (DAP) compared to monoammonium phosphate (MAP). The MC-treated compound with 4% Mo showed significantly less leaching than the control without ball milling when co-compacted with both MAP and DAP. In a pot trial with simulated leaching, the uptake of Mo was greater for the MC-treated 4% Mo compound co-compacted into DAP than for the other Mo sources. Overall, our results indicate that MC-treated MoO3–ZnO could be used as a slow-release Mo source in high-rainfall areas.

Graphical Abstract

Introduction

Molybdenum (Mo) and zinc (Zn) are essential nutrients for plant growth [29]. The dominant soluble Mo species in the soil is MoO42− (molybdate) and this anion is adsorbed by clay minerals and Fe and Al oxides in acid soils [19, 20]. Unlike most other essential cationic micronutrients (e.g., Cu and Zn), Mo availability decreases with decreasing pH [21]. In acidic soils, liming usually rectifies Mo deficiency, as absorbed Mo is released into the soil solution [6, 50]. However, in areas of high rainfall, Mo levels in soil may be low, due to losses through leaching and runoff [29]. In general, Mo toxic is rare but accumulation might cause safety issues with animal consumption. The safest limit of Mo for plants largely depends on the type of crop. For the optimum application rate of Mo as fertilizer Adams [3] suggested the optimum application rate of Mo fertilizer ranges from 0.1 to 0.3 kg ha−1 soil. Mo deficiency could largely decrease the crop yield, particularly for legumes as it is continuously required for symbiotic nitrogen fixation. Furthermore, other plants such as the Brassicaceae family are severely affected by molybdenum deficiency [17, 29]. Currently, soluble molybdates [Na2MoO4.2H2O and (NH4)6Mo7O24.4H2O] are commonly used as Mo fertilizers. Few studies have examined the use of slow-release Mo sources in fertilizers. A 1960s study reports the use of a Mo glassy frit in a field experiment [23] and found a greater residual effect on crop growth compared to a soluble Mo source. Bandyopadhyay et al. [9] proposed a Mo-containing long-chain magnesium sodium polyphosphate as a slow-release Mo fertilizer and found increased crop yield over the soluble Mo treatment in a field study. More recently, a layered double hydroxide (LDH) incorporated with Mo was proposed as a slow-release Mo fertilizer, with urea being a potential carrier to allow the slow-release character of the Mo source to be maintained [15].

Until now, Zn deficiency remains a global health problem. It affects more than 17% of the world’s population [40]. Zinc fertilizers can be applied by themselves, incorporated with macronutrients or applied in foliar sprays [38]. Compared to separate soil or foliar applications with a low rate of micronutrients, incorporating micronutrients with macronutrients is a more efficient way to reduce labour and spreading costs and to increase equal distribution of micronutrients in the field [16, 39].

Mechanochemistry is a green manufacturing method that has gained much attention in industrial synthesis for alloys, semiconductors, ceramics and pharmaceutical applications [8, 27]. Recent mechanochemical approaches to fertilizer synthesis have mainly focused on macronutrient NPK fertilizers. Several studies have been carried out to incorporate NPK nutrients into an inorganic matrix such as a clay mineral or LDH [10, 33, 47, 60]. Recently, mechanochemical methods have been used to combine alkaline metal salts with urea in organic co-crystals to produce more stable N fertilizers with reduced volatilization losses [11, 25, 26]. Only one study reported the mechanochemical incorporation of metal or metalloid oxides in a fertilizer using a ball mill. Yuan et al. [56] reported an amorphous glass phase of K–Si–Ca–O produced using CaO, SiO2, and KOH as reactants. The reactants were milled for 2 h and both the milling speed and the SiO2 content were adjusted to achieve optimal results. The optimal SiO2 content was chosen to perform a study of the K release rate versus the milling speed. They concluded that a slow-release K fertilizer can be obtained when the milling speed is above 300 rpm. Overall, few attempts have been made to synthesize micronutrient fertilizers using mechanochemistry [34, 46] and most mechanochemically synthesized products have only been tested for water solubility to indicate their effectiveness as slow-release fertilizers. However, solubility tests are not a good indicator of agronomic efficiency in soil [13, 38]. Therefore, it is crucial to assess newly synthesized fertilizers for their agronomic performance.

Zinc oxide is one of the cheapest and high analysis sources of Zn widely used in the fertilizer industry. Zinc oxide has low water solubility and high chemical stability, but its effectiveness as a fertilizer depends largely on the application method, soil pH, and (if applicable) the macronutrient it is incorporated with [35]. The efficiency of ZnO is similar or close to that of soluble Zn fertilizers such as ZnSO4 when optimum application methods are selected [24, 35, 38, 43]. Molybdenum-doped ZnO and ZnMoO4 have been synthesized by different chemical methods using ZnO and MoO3 [52, 53, 59] and have drawn much attention in the materials engineering industry as semiconductors and photocatalysts [55, 61]. Two of the products made were mechanochemically synthesized ZnO–MoO3 [57] and nickel molybdates [32]. In other industries, mechanochemistry has been proposed to prepare complex metal oxides, doped metal oxide, and metal oxide nanoparticles as functional materials [48, 58].

In this study, we aimed to incorporate Mo into the chemically stable ZnO structure or synthesize a new complex metal oxide using mechanochemistry. We hypothesized that mechanochemically synthesized ZnO–MoO3 variants are stable compounds with slow-release characteristics that could be useful as slow-release micronutrient compounds in fertilizers. In addition to the formulation and characterization, the resulting products were thoroughly assessed by (a) co-compacting Mo products into macronutrient fertilizers (muriate of potash—MOP, MAP and DAP); (b) performing column leaching using two soils; and (c) evaluating the effectiveness of the Mo-incorporated fertilizers in a plant uptake experiment with simulated leaching.

Methods

Mechanochemical synthesis and characterisation

Zinc oxide (ZnO, 99.0% puriss) from Sigma-Aldrich (NSW, Australia), molybdenum oxide (VI) (MoO3, 99.5%) from Merck (VIC, Australia) and ammonium molybdate tetrahydrate ((NH4)6Mo7O24·4H2O) from Chem-Supply (SA, Australia) were used as received.

Different amounts of (NH4)6Mo7O24·4H2O (AMT) or MoO3 were mixed with ZnO to obtain 3 g mixtures in total with Mo concentrations ranging from 1 to 36% as indicated in Table S1 (AMT samples) and Table 1 (MoO3 samples). The mixtures were milled in a 50-ml zirconia jar with six zirconia balls (15 mm diameter and 10 g per ball) to achieve a ball-to-powder weight ratio of 20. Ball milling was carried out in a planetary mill (PM200, Retsch, Haan, Germany) for 8 h at a rotation speed of 550 rpm with a break of 5 min and a change of direction every 30 min to avoid overheating. The parameters were chosen to get higher input energy (maximum speed is 650 rpm for the PM200 planetary mill). The 8 h was chosen to achieve optimum and effective milling with the lowest crystallite size and highest lattice strain as indicated in other literature [5]. The milled products were characterized by X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. X-ray diffraction patterns of products and reactants were recorded with an X'Pert Pro multipurpose diffractometer (PANalytical B.V. Almelo, Netherlands) using Fe-filtered Co Kα radiation, automatic divergence slit, 2° anti-scatter slit, and fast X'Celerator Si strip detector. The diffraction patterns were recorded in steps of 0.017° 2-theta with a counting time of 0.5 s per step for an overall counting time of approximately 30 min. The relative amounts of the major phases were determined by the Rietveld method using the Bruker TOPAS software package (Bruker BioSpinCorporation, Billerica, MA, USA). Fourier transform infrared spectroscopy measurement was carried out using the attenuated total reflectance (ATR) module on an Alpha FT-IR spectrometer (Bruker Optics, Ettlingen, Germany). The analysis was performed in the middle infrared range (wavenumber from 4000 to 400 cm−1) at a resolution of 4 cm−1 and corrected for an air background. The sample was mounted on a platinum platform and covered with a thin layer of foil paper. Each sample was scanned 100 times and the platform was cleaned with lint-free tissue and ethanol between treatments. The morphology of the synthesized products was imaged using field emission scanning electron microscopy (FE-SEM, Quanta 450, FEI, USA).

Table 1 The mechanochemical treatments of MoO3 and ZnO milled with different Zn:Mo ratios for 8 h
Full size table

Batch solubility, fertilizer manufacturing, and column dissolution

Batch solubility tests were conducted to assess the solubility of the mechanochemically treated Mo–ZnO products from both AMT and MoO3 (1, 2, 4, 8, 10 and 33/36% Mo). In addition, we also tested the 4% and 36% Mo-Control, which had the same MoO3–ZnO reactant mixture, but without ball milling. The solubility of the samples was evaluated by weighing 0.1 g of the sample in a 50 ml digestion tube with 10 ml of reverse osmosis (RO) water. Samples were shaken on an end-to-end shaker for 1 h followed by 10 min centrifugation at 4685 g and pH was determined. Samples were filtered through a 0.2-µm syringe filter before analysis. The sediment remaining in the centrifuge tubes was digested overnight at room temperature using aqua regia (HNO3: HCl = 1:3 v/v), followed by 45 min of heating at 80 °C and 165 min of heating at 125 °C in hot block digestion. All samples were analyzed by inductively coupled plasma-optical emission spectrometry (ICP–OES, Avio 200, Perkin Elmer, Waltham, USA) to determine the total content of soluble and insoluble Mo and Zn.

The compaction of micronutrient and macronutrient fertilizer powders was carried out using a pellet press. The selected micronutrient samples were the compounds made using MoO3 and ZnO with 4% or 36% Mo. Also, mixtures of MoO3 and ZnO without mechanochemical treatment were included for comparison, as well as a mixture of AMT and ZnSO4·7H2O as a soluble reference treatment. Granules of MOP (muriate of potash, KCl), MAP (monoammonium phosphate) and DAP (diammonium phosphate) were ground, sieved (< 250 μm) and mixed with the Mo products (Table 2) before adding 1 ml of DI water to 5 g of mixed powder to form a paste. The paste was placed in a 4-cm diameter die and 9.8 MPa pressure was applied using a pellet press (Simplex 12HJ Templeton Kenlyand Co, IL, USA) to form a single pellet. The pellet was air-dried and cut into small pellets of similar size (2–3 mm square) and weights (around 40 mg).

Table 2 The amount of micronutrient compound added to macronutrient fertilizers with or without mechanochemical treatment
Full size table

Release of Mo and Zn from these products was tested using the column perfusion method described by Baird et al. [7]. This is a laboratory method that examines the dynamic release of nutrients from fertilizer formulations by continuously perfusing samples with a solution in real time. Previous studies have shown a good correlation between pot, leaching, and seedling toxicity experiments with this method [1, 2, 14]. Pellet samples (0.2 g) were placed between 1 g of glass wool in each polypropylene column (150 mm long × 15 mm diameter). The percolating solution (RO water) was introduced into the column from the bottom using a peristaltic pump at a constant rate of 10 ml h−1. The solutions released from the top of the column were collected every hour for 72 h using a fraction collector (SuperFracTM, Pharmacia, USA). At the end of the study, the residues, the glass wool and the solution remaining in each column were collected and dried in the oven at 90° C until all the liquid vaporized. These residues were digested using hot aqua regia, analyzed by ICP–OES, and added to all nutrients released over time to establish the total nutrient content of the sample. The nutrient release was expressed as a percentage of this total content. All column dissolutions were performed in duplicate.

Leaching in soil

A column leaching experiment was performed to examine the release of Mo from the fertilizers in an acid soil and in a calcareous soil, with both considered to have low to very low fertility (for soil properties see Table S2). The columns consisted of syringes (120 mm length and 15 mm diameter) that were filled with a layer of glass wool and 30 g of soil. Around 400 mg of fertilizer (circa 10 granules) was evenly distributed throughout the soil column. Treatments were DAP or MAP alone or cogranulated with the mechanochemically treated compound (MC), the non-treated MoO3–ZnO mixture (C) or the soluble Mo and Zn sources (AMT) (Table 2). Deionized water was introduced to the column from the bottom to the top using a peristaltic pump at a constant rate. The soil was first saturated until no dry soil was observed; then 30 ml of deionized water was added to leach the column from the top on day 1 and day 3 followed by six leaching events with 20 ml of DI water every 2 or 3 days. After each leaching, the column was incubated at a constant temperature of 25 °C. After the final leaching, the soil in each column was dried in the oven and further homogenized by grinding using a mortar and pestle. The soil was then subsampled and digested to determine total Mo concentrations. The collected and filtered leachate after each leaching and digested soil extract were analyzed using ICP–OES.

Pot trial

The pot trial was conducted in a glasshouse using pure sand as a growth medium. The pure sand was used for pot trial due to low Mo plant uptake (below detection limits) in a preliminary study. Chickpea was selected due to the high demand for Mo by legumes. Plastic pots (120 mm diameter and 120 mm height) with a few layers of mesh placed at the bottom were filled with 1 kg of washed sand. For each pot, 5 granules (0.2 g of fertilizer treatments mentioned in the leaching study, containing around 0.4 mg Mo and 7.6 mg Zn), corresponding to 0.28 kg Mo ha−1 soil assuming a bulk density of 1.4 g cm−3, were placed 4.5 cm equidistantly below the soil surface. Leaching was carried out two days later to allow the dissolution of the fertilizer before leaching. The initial water content of the sand, prior to leaching, was 4%. Treatments were randomized with 4 replicates of each treatment using a complete block design generated by GenStat 19th edition. The leaching procedure was performed with DI water. Each pot was leached four times with 350 ml (or a total of approximately four pore volumes) of water to mimic heavy rainfall events which could remove soluble Mo from the fertilizer and soil. The leachates of each pot were collected and filtered before the determination of solution pH and Mo concentrations by ICP analysis. After the leaching events, the pots were left in ambient conditions for 3 days before planting. The chickpea (anti-fungi treated) was germinated for 2 days in the dark at a constant temperature of 25 °C. Germinated seeds (3 seeds per pot) were transplanted 2.5 cm below the soil surface and thinned to 1 after 2 weeks. All pots received 10 ml of basal nutrient solution 5 days after planting and every week during the growing period (7 times in total). Total amounts of nutrients supplied by the basal nutrient solution were 63 mg N kg−1, 198 mg P kg−1, 250 mg K kg−1 90 mg Ca kg−1, 150 mg S kg−1, 15 mg Mg kg−1, 5 mg Mn kg−1, 5 mg Fe kg−1, 0.5 mg Cu kg−1, 0.05 mg B kg−1, and 0.05 mg Co kg−1. All pots were maintained at 50% field capacity by checking their weights every day and adding DI water as needed. Harvesting was carried out at flowering (stage R1) 7 weeks after planting. Plant shoots were cut 1 cm above the soil surface and roots were collected and washed with DI water. Both roots and shoots were oven dried for 72 h at 60 °C for dry mass weight and further ground and digested before ICP analysis for Mo content.

For statistical analysis, one-way and two-way ANOVA (analysis of variance) was used followed by Duncan's multiple range test (MRT) to check significant differences using GenStat (19th edition). Where needed, the data were log-transformed to homogenize variance.

Results and discussion

Solubility of mechanochemically treated Mo–ZnO and characteristics of materials

The measured total Mo content was close to the expected content for both AMT and MoO3 treatments (Table S3). Molybdenum release was much higher for the AMT than for the MoO3 treatments (Fig. 1a). Molybdenum solubility increased with increasing Mo content for both MoO3 and AMT treatments up to a Mo content of 10%, where all Mo was dissolved for the AMT treatment and ~ 30% for the MoO3 treatment. At the highest Mo content (33%), Mo in the AMT treatment was fully dissolved, while the solubility for the MoO3 (36% Mo) treatment was lower than the treatment with 10% Mo. The 4% and 36% Mo control treatments (without mechanochemical processing) released more than twice the Mo compared to the mechanochemically treated samples. This is likely due to the formation of new compounds with higher Mo solubility in water. Given the high solubility of the AMT incorporated compounds, only compounds made with MoO3 were further evaluated. The 4% Mo was selected because of its suitable Zn/Mo ratio for agronomic purposes (ratio similar to that of common Zn/Mo fertilizer rates) and the 36% Mo, because newly formed compounds were found in this material (see below).

Fig. 1
figure 1

a Solubility of Mo for mechanochemically treated ZnO with different amounts of MoO3 and (NH4)6Mo7O24·4H2O after 1 h equilibration in water; b FTIR and c XRD patterns of mechanochemically treated ZnO with different amounts of MoO3; d FTIR and e XRD of the reactants

Full size image

The FTIR spectra of mechanochemically treated samples showed a different pattern compared to the reactants, ZnO and MoO3 (Fig. 1b, d and Figure S2 magnified in the range of 500–1500 cm−1) as increased Mo content modified the peak intensity and position. The peak at 851 cm−1 in the 2% Mo sample shifted to 899 cm−1 at 4% Mo and split to a shoulder peak at 909 and 806/798 cm−1 for the 8% and 10% formulations. The peaks at 851, 899 and 909 cm−1 are likely ascribed to the Mo–O–Mo vibration of Mo6+ in [MoO4] clusters [12]. The observed shoulder peaks observed in the 8 and 10% Mo at 806 and 789 cm−1 could be assigned to antisymmetric stretching of Mo–O [54]. Characteristic peaks of MoO3 (Fig. 1d) and Zn–O–Mo (1100–1400 cm−1) were not observed in the 2–10% Mo samples [55]. The FTIR spectra of the 36% Mo sample are in line with the FTIR spectra of ZnMoO4 reported in an earlier study [54]. It can be concluded that the chemical structure of the reactants has changed after ball milling.

Changes in the XRD patterns with increased milling time further support differences in chemical structure observed with FTIR. The six clear peaks in the samples incorporated with 2–10% MoO3 could be assigned to the wurtzite phase of ZnO (Fig. 1c), but they were broader than in the control samples [55]. In the control sample, the peaks assigned to MoO3 were clearly visible even at lower Mo content (Figure S3a), but these peaks completely disappeared in the mechanochemically treated samples with 2–10% Mo (Fig. 1c). However, a broad bump was observed around 2 theta = 31° when the percentage of Mo increased to 8% which was in line with the FTIR results where the shoulder peaks (between 800 and 900 cm−1) appeared. This could be due to an increase in the Mo concentration that indicated reduction of inter-planar “d” spacing in the sample [4]. When the Mo content increased to 36%, in addition to the identifiable ZnO peaks and minor peaks assigned to MoO3 (Figure S3b), many new peaks assigned to several zinc molybdates and zinc molybdenum oxide were observed (Figure S3b) [51]. A calculation using the Scherrer equation confirmed the decrease of crystallite size to approximately 1.5–2.0 nm for low Mo concentration samples after mechanochemical treatment (data not shown) [42]. Therefore, the much smaller crystallite size of ZnO obtained after MC treatment with MoO3 was likely due to smaller Mo6+ (0.065 nm) doped into and replacing Zn2+ in the ZnO structure, thus suppressing the growth of ZnO crystals [55]. Overall, these results indicate that the mechanochemically treated samples at a low Mo inclusion rate successfully penetrated the wurtzite crystalline lattice of ZnO, particularly at 2% and 4% Mo, where no impurity peaks were observed [49], while the crystal structure changed at the highest 36% Mo rate as a result of new compound formation.

Column dissolution of Mo compacted with MAP, MOP, and DAP

All pelletized samples were macronutrient fertilizers containing a final Mo concentration of 0.2% as indicated in Table 2. Both macronutrients (K and P) were quickly released from the formulations and no difference in the macronutrient release was observed between Mo treatments (Figure S4a, c). Total Mo released from DAP and MAP was twice as high in the treatments with the 36% Mo compounds, reaching 80% and 70%, respectively, compared to those with the 4% Mo compounds (Fig. 2a, b). The Mo release for the 4% Mo treatments was half that of the 4% Mo-Control for both the MAP and DAP treatments. The Mo release from MAP + 4% Mo was slow and constant, while in DAP + 4% Mo, a dual release was observed where the release was fast in the initial 10 h (39%), followed by a minor release (3%) in the following 62 h. This is likely due to the pH initially changing in the solution to slightly alkaline with DAP and acidic with MAP dissolution. The alkaline solution from DAP could quickly dissolve all the Mo that was not incorporated into the ZnO structure [45]. On the other hand, an acidic solution from MAP treatment releases Mo through dissolving ZnO, which is slowly released over time. In the MOP treatments, more than 80% of the total Mo was released after 72 h of dissolution. Total Zn release was negligible in most treatments (< 6%) over 72 h, except for MOP + 36% Mo and MAP + 36% Mo where 70% and 18% of the total Zn was released, respectively. The higher release rate of Mo and Zn in MOP + 36% Mo and MAP + 36% Mo is likely due to the presents of high concentration of other salts, such as KCl. The lower percentage release of Zn in the 4% Mo treatments was likely due to (i) the 36% Mo treatments containing ZnMoO4 had a much higher Zn solubility compared to ZnO, and a faster rate of Zn release and (ii) the higher ZnO content of the 4% Mo treatments had higher absolute amount of Zn. Overall, the column dissolution indicated that the DAP + 4% Mo and MAP + 4% Mo behaved as slow-release Mo Fertilizers. Leaching in soil and a pot trial were performed to further evaluate the agronomic effectiveness of these two treatments.

Fig. 2
figure 2

The cumulative release over 72 h of (a, b, c) Mo, and (d, e, f) Zn (as % of added) from MAP, MOP and DAP compacted with 0.2% Mo, either as (a, d) the mechanochemically treated compounds with 36% Mo or (b, e) 4% Mo with (c, f) or the 4% Mo-Control without mechanochemical treatment. Error bars present the standard error of the mean (n = 2)

Full size image

Molybdenum leaching from fertilizers in soils

Leaching of Mo was assessed in two contrasting soils. For all treatments, Mo incorporated with DAP had higher Mo leaching compared to MAP (Fig. 3). When Mo sources were applied with MAP, the lowest Mo leaching was observed in AMT and MC treatments in both soils, both circa half that of the C treatment. The leached Mo from C was 66% in Ngarkat soil and 93% in Streaky Bay soil at the end of incubation (Fig. 3e, f). When Mo sources were applied with DAP, the Mo release was lowest with MC treated products (Fig. 3g, h). Molybdenum leached from MC treatments was approximately 20% lower in Ngarkat soil and 40% in Streaky Bay soil compared to C and AMT treatments. The Mo leached over time in both soils followed the same trend as the pH changes, with an increase in Mo leaching as the pH of the leachate increased (Fig. 3a–d). Molybdenum recovery in the soil corresponded well with the leaching results except for C with DAP in the Ngarkat soil, where no residue was recovered, despite incomplete leaching. This may have been due to heterogeneity of the soil sample or residues remaining attached to the glass wool. The amount of retained Mo in the soil after leaching was higher for the MC treatments than the other treatments, except with MAP in the Ngarkat soil where AMT and MC retained a similar amount (Fig. 3i). For the C treatment, Mo in the soil was detected only in Ngarkat soil with MAP as the carrier.

Fig. 3
figure 3

The (a, b, c, d) pH of the leachate and (e, f, g, h) cumulative Mo (% of added Mo) leached from columns at each leaching day from Ngarkat and Streaky Bay soils; i digested residual Mo in the soils after the leaching events. The table shows the micronutrients added to the treatments while the letters represent the treatments. Error bars present the standard error of the mean (n = 6)

Full size image

Overall, Mo release was affected by the soil, most likely due to differences in the soil pH [44]. Most treatments had lower Mo recovery in the alkaline Streaky Bay soil than in the neutral Ngarkat soil except for MC + DAP. This is consistent with the theory that typical well-drained, near-neutral sandy soils or calcareous soils with organic matter less than 50 g kg−1 tend to retain little Mo [18, 41]. Moreover, the Mo release from the pellet is also largely affected by the pH induced by the macronutrient carrier. With the same Mo source and soil, the Mo release was higher for DAP compared to MAP due to the higher solution pH around DAP granules, except for C treatments where most of the Mo leached out within the first 3 days in the Streaky Bay soil. Due to the lower pH of the leachate in AMT compared to C, the leached Mo was higher for C in all treatments, except the DAP treatments applied in the Streaky Bay soil, where most Mo leached out by day 3. Interestingly, the MC and C treatments had a similar pH in the leachate over the six leaching events, while the release of Mo was 20–50% lower for MC compared to C treatments regardless of the soil and carrier. The results, therefore, suggest that the MC treatments might be less affected by soil pH compared to the C and AMT treatments.

Pot trial

More Mo was leached from DAP treatments than from the MAP treatments (Fig. 4a, b). The highest recovery of Mo in the leachate was observed in the DAP treatment with C, for which more than 70% of added Mo was found in the leachate (Fig. 4b), while only 13% was leached for the corresponding treatment with MAP (Fig. 4a). The lowest Mo recovery in leachate was observed in the MAP + MC treatment (5%). With DAP as the carrier, the Mo recovery from the MC treatment reached 39% in the leachate. The AMT treatments behaved similarly for both MAP and DAP fertilizers, with 17–25% of the added Mo leached after four leaching events. Surprisingly, the Mo leaching from the soluble AMT treatment was lower than that of the MC treatment for DAP (Fig. 4d). This can perhaps be explained by the lower leachate pH for the AMT treatment than for the MC treatment. Furthermore, the pH of leachates was higher for DAP than for MAP across all treatments (Fig. 4c, d). In agreement with column leaching, the recovery of Mo in the leachate was closely associated with the pH of the leachate. Leaching of Zn was observed only in the AMT treatment with MAP as the carrier (Figure S5a). Despite the use of soluble ZnSO4·7H2O in the AMT treatment, leaching of Zn from the sandy medium for the AMT treatment with DAP was low, likely due to precipitation of Zn with P compounds under the higher pH environment, such as NH4ZnPO4 and hopeite [Zn3(PO4)2·4H2O] [37].

Fig. 4
figure 4

a, b Amount of Mo recovered in the leachate (expressed as a percentage of added) and (c,d) pH of the leachate for MAP or DAP alone (N), or co-compacted with soluble Mo and Zn sources (AMT treatment), non-treated oxides (C treatment) or mechanochemically treated oxides (MC treatment) in the pot experiment collected after 4 consecutive leaching events of one pore volume each (L1 to L4). Error bars present the standard error of the mean (n = 4). Different letters indicate statistical (P ≤ 0.05) differences between Mo treatments using a one-way ANOVA; Duncan's MRT

Full size image

The shoot and root dry weights were significantly lower in the DAP + AMT treatment than in the treatment with DAP alone and the shoot dry weight of DAP + MC was significantly higher than the treatment with DAP alone (Fig. 5a, d). The lower yield for the DAP + AMT treatment may have been due to dissolved Zn2+ from ZnSO4·7H2O causing toxicity [30] as the sand had no or minimal cation exchange capacity. In the MAP treatments, there were no significant differences in yield between the treatments (Fig. 5a, d).

Fig. 5
figure 5

a, d Shoot and root dry matter yields, b, e Mo concentrations in the shoots and roots, and c, f Mo uptake in shoots and roots of chickpea in response to application of MAP, DAP alone (N) or co-compacted with soluble Mo and Zn sources (AMT treatment), non-treated oxides (C treatment) or mechanochemically treated oxides (MC treatment). Error bars present the standard error of the mean (n = 4). Different letters indicate significant differences between treatments for a given macronutrient carrier—capital letter assigned to MAP and small letter assigned to DAP. Significance of Mo treatments (Mo) and their interactions (Carriers × Mo) are indicated by asterisks above each figure (*P ≤ 0.05; **P ≤ 0.01; ***P ≤ 0.001; ns, not significant; using two-way ANOVA; Duncan's MRT)

Full size image

For both macronutrient carriers, the effect of Mo addition on Mo concentration and uptake was much higher in the root than in the shoot (Fig. 5b, c, e and f). The highest shoot Mo concentrations were observed in MAP/DAP + MC and MAP + C treatments (Fig. 5b). The small but detectable Mo shoot concentrations in the N treatments were likely derived from the chickpea seed itself as the pure sand did not contain a detectable amount of Mo. Concentrations of Mo in roots were highest for AMT and MC in the DAP treatments, and highest for MC and C in the MAP treatments (Fig. 5e). The Mo uptake in roots and shoots followed the order MC > C = AMT ≥ N when DAP was the carrier and MC = C > AMT > N when MAP was the carrier (Fig. 5c, f). The lower Mo uptake observed for the MAP + AMT treatment compared to the other Mo treatments was likely due to both AMT and zinc sulphate fertilizer acidifying the sand solution around roots, thus reducing Mo uptake (Gammon Jr et al., 1954). This is supported by the leaching results where AMT treatments had much lower pH than the control and other Mo-added treatments (Fig. 4c). Moreover, the pure sand had a very low soil cation exchange capacity, thus the decreased soil pH will also have increased Zn bioavailability and further caused plant phytotoxicity.

The availability of Mo is controlled by the pH of the soil solution. Many studies have concluded that liming along with Mo application can promote Mo availability and improve Mo uptake by plants [22, 36]. In soil, Mo movement or leaching is mainly affected by soil pH. Johansen et al. [28] conducted a field trial on tropical pasture legumes using MoO3 and sodium molybdate and reached a similar conclusion that soil pH influences Mo movement. Furthermore, they also concluded that there was no difference in residual effects on legume growth between the two Mo sources they applied. Therefore, in our study, plant uptake of Mo was likely affected by the pH of both the macronutrient carrier and the soil solution, as well as the solubility of the Mo source.

Overall, the MC treatment resulted in slower Mo release and protected Mo against leaching, resulting in higher uptake than for the control (without MC treatment) when DAP was the carrier. There was no significant difference in plant uptake between the MC and control treatment when MAP was the carrier, likely because there was less Mo leaching with MAP for all the treatments (due to the lower pH induced by MAP). However, our experiments were carried out at high fertilizer rates (columns) or with a pure sand (pot trial). In field soils with higher pH buffering capacity, the fertilizer carrier would likely have less effect on soil pH and there would be less chance of Zn toxicity with more soluble treatments (e.g., AMT). Further work is, therefore, recommended to compare these fertilizer sources in soil systems.

Conclusions

The MC synthesized Mo–Zn fertilizer was found to be less prone to leaching than currently used Mo sources [MoO3 and (NH4)6Mo7O24·4H2O]. In addition, the lower leaching loss was found to result in higher Mo uptake compared to a non-treated control when DAP was the fertilizer carrier. Therefore, the mechanochemically synthesized Mo–Zn fertilizer has promise as a slow release fertilizer for application in high rainfall areas, light textured soils and/or soils with high pH. The MC method used in this study did not require water or solvent and did not produce any waste streams. Compared to other methods in the literature preparing similar doped material, the mechanochemical approach requires less procedure such as hours of magnetic stirring, oven drying, calcination and purification with ethanol or water [31, 55]. To promote this green synthesis method, agronomic comparisons with conventional fertilizers are essential. This study demonstrated the importance of agronomically assessing new fertilizers, especially when examining micronutrients, as micronutrients are required in only small amounts and their availability is more likely to be affected by other nutrients applied at the same time. Informed selection of macronutrient carriers can greatly change the effectiveness of applied micronutrients. However, pot trials cannot guarantee performance in all agronomic situations. The soils used in this study were sandy with a low ability to adsorb Mo, unlike heavier soils where Mo fixation might become a dominant parameter affecting plant Mo uptake. Further, other climates with less rainfall might affect the efficiency of the proposed products. Therefore, further pot and field trials with different soils and climates are required to further evaluate the effectiveness of these synthesized products.

Availability of data and materials

The data sets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Abbreviations

MC:

Mechanochemistry

DAP:

Diammonium phosphate

MAP:

Monoammonium phosphate

LDH:

Layered double hydroxide

AMT:

(NH4)6Mo7O24·4H2O

XRD:

X-ray diffraction

FTIR:

Fourier transform infrared

FE-SEM:

Field-emission scanning electron microscopy

ICP–OES:

Inductively coupled plasma–optical emission spectrometry

g:

Relative centrifugal force

References

  1. Abat M, Degryse F, Baird R, McLaughlin MJ. Boron phosphates (BPO4) as a seedling-safe boron fertilizer source. Plant Soil. 2015;391(1):153–60. https://doi.org/10.1007/s11104-015-2424-6.

    Article  CAS  Google Scholar 

  2. Abat M, Degryse F, Baird R, McLaughlin MJ. Responses of canola to the application of slow-release boron fertilizers and their residual effect. Soil Sci Soc Am J. 2015;79(1):97–103. https://doi.org/10.2136/sssaj2014.07.0280.

    Article  CAS  Google Scholar 

  3. Adams JF. Yield response to molybdenum by field and horticultural crops. In: Gupta UC, editor. Molybdenum in agriculture. Cambridge: Cambridge University Press; 1997. p. 182–210.

    Chapter  Google Scholar 

  4. Ali A, Ammar M, Ali M, Yahya Z, Javaid MY, Hassan SU, Ahmed T. Mo-doped ZnO nanoflakes on Ni-foam for asymmetric supercapacitor applications. RSC Adv. 2019;9(47):27432–8. https://doi.org/10.1039/C9RA05051E.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  5. Amirkhanlou S, Ketabchi M, Parvin N. Nanocrystalline/nanoparticle ZnO synthesized by high energy ball milling process. Mater Lett. 2012;86:122–4. https://doi.org/10.1016/j.matlet.2012.07.041.

    Article  CAS  Google Scholar 

  6. Anderson AJ. Molybdenum as a fertilizer. In: Norman AG, editor. Advances in agronomy. Cambridge: Academic Press; 1956.

    Google Scholar 

  7. Baird R, da Silva RC, Degryse F, McLaughlin MJ. A column perfusion test to assess the kinetics of nutrient release by soluble sparingly soluble and coated granular fertilizers. J Plant Nutr Soil Sci. 2019. https://doi.org/10.1002/jpln.201800666.

    Article  Google Scholar 

  8. Baláž P, Achimovičová M, Baláž M, Billik P, Cherkezova-Zheleva Z, Criado JM, Delogu F, Dutková E, Gaffet E, Gotor FJ, Kumar R, Mitov I, Rojac T, Senna M, Streletskii A, Wieczorek-Ciurowa K. Hallmarks of mechanochemistry: from nanoparticles to technology. Chem Soc Rev. 2013;42(18):7571–637. https://doi.org/10.1039/C3CS35468G.

    Article  PubMed  Google Scholar 

  9. Bandyopadhyay S, Bhattacharya I, Ghosh K, Varadachari C. New slow-releasing molybdenum fertilizer. J Agric Food Chem. 2008;56(4):1343–9. https://doi.org/10.1021/jf072878g.

    Article  CAS  PubMed  Google Scholar 

  10. Borges R, Prevot V, Forano C, Wypych F. Design and kinetic study of sustainable potential slow-release fertilizer obtained by mechanochemical activation of clay minerals and potassium monohydrogen phosphate. Ind Eng Chem Res. 2017;56(3):708–16. https://doi.org/10.1021/acs.iecr.6b04378.

    Article  CAS  Google Scholar 

  11. Casali L, Mazzei L, Shemchuk O, Honer K, Grepioni F, Ciurli S, Braga D, Baltrusaitis J. Smart urea ionic co-crystals with enhanced urease inhibition activity for improved nitrogen cycle management. Chem Commun. 2018;54(55):7637–40. https://doi.org/10.1039/C8CC03777A.

    Article  CAS  Google Scholar 

  12. Chen Y, Lu C, Xu L, Ma Y, Hou W, Zhu J-J. Single-crystalline orthorhombic molybdenum oxide nanobelts: synthesis and photocatalytic properties. CrystEngComm. 2010;12(11):3740–7. https://doi.org/10.1039/C000744G.

    Article  CAS  Google Scholar 

  13. Chien SH, Prochnow LI, Tu S, Snyder CS. Agronomic and environmental aspects of phosphate fertilizers varying in source and solubility: an update review. Nutr Cycl Agroecosyst. 2011;89(2):229–55. https://doi.org/10.1007/s10705-010-9390-4.

    Article  Google Scholar 

  14. da Silva R, Baird R, Degryse F, McLaughlin MJ. Slow and fast-release boron sources in potash fertilizers: spatial variability, nutrient dissolution and plant uptake. Soil Sci Soc Am J. 2018;82(6):1437–48. https://doi.org/10.2136/sssaj2018.02.0065.

    Article  CAS  Google Scholar 

  15. Everaert M, Smolders E, McLaughlin MJ, Andelkovic I, Smolders S, Degryse F. Layered double hydroxides as slow-release fertilizer compounds for the micronutrient molybdenum. J Agric Food Chem. 2021;69(48):14501–11. https://doi.org/10.1021/acs.jafc.1c06056.

    Article  CAS  PubMed  Google Scholar 

  16. Ferguson D, Olson R, Heinbigner C, Compacted muriate of potash fertilizers containing micronutrients and methods of making same. Google Patents. 2016

  17. Gammon N Jr, Volk GM, McCubbin EN, Eddins AH. Soil factors affecting molybdenum uptake by cauliflower. Soil Sci Soc Am J. 1954;18(3):302–5. https://doi.org/10.2136/sssaj1954.03615995001800030018x.

    Article  Google Scholar 

  18. Goldberg S, Forster HS. Factors affecting molybdenum adsorption by soils and minerals. Soil Sci. 1998. https://doi.org/10.1097/00010694-199802000-00004.

    Article  Google Scholar 

  19. Goldberg S, Forster HS, Godfrey CL. Molybdenum adsorption on oxides, clay minerals, and soils. Soil Sci Soc Am J. 1996;60(2):425–32. https://doi.org/10.2136/sssaj1996.03615995006000020013x.

    Article  CAS  Google Scholar 

  20. Goldberg S, Lesch SM, Suarez DL. Predicting molybdenum adsorption by soils using soil chemical parameters in the constant capacitance model. Soil Sci Soc Am J. 2002;66(6):1836–42. https://doi.org/10.2136/sssaj2002.1836.

    Article  CAS  Google Scholar 

  21. Gustafsson JP, Tiberg C. Molybdenum binding to soil constituents in acid soils: an XAS and modelling study. Chem Geol. 2015;417:279–88. https://doi.org/10.1016/j.chemgeo.2015.10.016.

    Article  CAS  Google Scholar 

  22. Hagstrom GR, Berger KC. Molybdenum status of three Wisconsin soils and its effect on four legume crops1. Agron J. 1963;55(4):399–401. https://doi.org/10.2134/agronj1963.00021962005500040031x.

    Article  CAS  Google Scholar 

  23. Henkens CH, Smilde KW. Evaluation of glassy frits as micronutrient fertilizers. 1. Copper and molybdenum frits. Neth J Agric Sci. 1966;14:165–77.

    CAS  Google Scholar 

  24. Hergert GW, Rehm GW, Wiese RA. Field evaluations of zinc sources band applied in ammonium polyphosphate suspension. Soil Sci Soc Am J. 1984;48(5):1190–3. https://doi.org/10.2136/sssaj1984.03615995004800050048x.

    Article  CAS  Google Scholar 

  25. Honer K, Kalfaoglu E, Pico C, McCann J, Baltrusaitis J. Mechanosynthesis of magnesium and calcium salt-urea ionic cocrystal fertilizer materials for improved nitrogen management. ACS Sustain Chem Eng. 2017;5(10):8546–50. https://doi.org/10.1021/acssuschemeng.7b02621.

    Article  CAS  Google Scholar 

  26. Honer K, Pico C, Baltrusaitis J. Reactive mechanosynthesis of urea ionic cocrystal fertilizer materials from abundant low solubility magnesium- and calcium-containing minerals. ACS Sustain Chem Eng. 2018;6(4):4680–7. https://doi.org/10.1021/acssuschemeng.7b03766.

    Article  CAS  Google Scholar 

  27. James SL, Adams CJ, Bolm C, Braga D, Collier P, Friščić T, Grepioni F, Harris KDM, Hyett G, Jones W, et al. Mechanochemistry: opportunities for new and cleaner synthesis. Chem Soc Rev. 2012;41(1):413–47. https://doi.org/10.1039/C1CS15171A.

    Article  CAS  PubMed  Google Scholar 

  28. Johansen C, Kerridge PC, Luck PE, Cook BG, Lowe KF, Ostrowski H. The residual effect of molybdenum fertilizer on growth of tropical pasture legumes in a sub-tropical environment. Aust J Exp Agric. 1977;17(89):961–8.

    Article  CAS  Google Scholar 

  29. Kaiser BN, Gridley KL, Ngaire Brady J, Phillips T, Tyerman SD. The role of molybdenum in agricultural plant production. Ann Bot. 2005;96(5):745–54. https://doi.org/10.1093/aob/mci226.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Kaur H, Garg N. Zinc toxicity in plants: a review. Planta. 2021;253(6):129. https://doi.org/10.1007/s00425-021-03642-z.

    Article  CAS  PubMed  Google Scholar 

  31. Khalid NR, Sabir M, Ali F, Tahir MB, Javid MA, Niaz NA, Ahmed R, Rafique M, Imran M, Assiri MA. Green synthesis and characterizations of bi-functional Mo-doped ZnO nanostructures for antimicrobial and photocatalytic applications. Mater Chem Phys. 2023;296: 127306. https://doi.org/10.1016/j.matchemphys.2023.127306.

    Article  CAS  Google Scholar 

  32. Klissurski D, Mancheva M, Iordanova R, Tyuliev G, Kunev B. Mechanochemical synthesis of nanocrystalline nickel molybdates. J Alloy Compd. 2006;422(1):53–7. https://doi.org/10.1016/j.jallcom.2005.11.073.

    Article  CAS  Google Scholar 

  33. Lei Z, Cagnetta G, Li X, Qu J, Li Z, Zhang Q, Huang J. Enhanced adsorption of potassium nitrate with potassium cation on H3PO4 modified kaolinite and nitrate anion into Mg-Al layered double hydroxide. Appl Clay Sci. 2018;154:10–6. https://doi.org/10.1016/j.clay.2017.12.040.

    Article  CAS  Google Scholar 

  34. Li X, Lei Z, Qu J, Li Z, Zhou X, Zhang Q. Synthesizing slow-release fertilizers via mechanochemical processing for potentially recycling the waste ferrous sulfate from titanium dioxide production. J Environ Manage. 2017;186:120–6. https://doi.org/10.1016/j.jenvman.2016.10.058.

    Article  CAS  PubMed  Google Scholar 

  35. McBeath TM, McLaughlin MJ. Efficacy of zinc oxides as fertilisers. Plant Soil. 2014;374(1):843–55. https://doi.org/10.1007/s11104-013-1919-2.

    Article  CAS  Google Scholar 

  36. McBride MB, Cherney J. Molybdenum, sulfur, and other trace elements in farm soils and forages after sewage sludge application. Commun Soil Sci Plant Anal. 2004;35(3–4):517–35. https://doi.org/10.1081/CSS-120029729.

    Article  CAS  Google Scholar 

  37. Milani N, McLaughlin MJ, Stacey SP, Kirby JK, Hettiarachchi GM, Beak DG, Cornelis G. Dissolution kinetics of macronutrient fertilizers coated with manufactured zinc oxide nanoparticles. J Agric Food Chem. 2012;60(16):3991–8. https://doi.org/10.1021/jf205191y.

    Article  CAS  PubMed  Google Scholar 

  38. Montalvo D, Degryse F, da Silva RC, Baird R, McLaughlin MJ. Agronomic effectiveness of zinc sources as micronutrient fertilizer. Amsterdam: Elsevier; 2016.

    Book  Google Scholar 

  39. Mortvedt JJ, Gilkes RJ. Zinc Fertilizers. In: Robson AD, editor. Zinc in Soils and Plants. Dordrecht: Springer, Netherlands; 1993. p. 33–44.

    Chapter  Google Scholar 

  40. Myers SS, Wessells KR, Kloog I, Zanobetti A, Schwartz J. Effect of increased concentrations of atmospheric carbon dioxide on the global threat of zinc deficiency: a modelling study. Lancet Glob Health. 2015;3(10):e639-645. https://doi.org/10.1016/s2214-109x(15)00093-5.

    Article  PubMed  PubMed Central  Google Scholar 

  41. O’Connor GA, Brobst RB, Chaney RL, Kincaid RL, McDowell LR, Pierzynski GM, Rubin A, Van Riper GG. A modified risk assessment to establish molybdenum standards for land application of biosolids. J Environ Qual. 2001;30(5):1490–507. https://doi.org/10.2134/jeq2001.3051490x.

    Article  CAS  PubMed  Google Scholar 

  42. Patterson AL. The scherrer formula for X-ray particle size determination. Phys Rev. 1939;56(10):978–82. https://doi.org/10.1103/PhysRev.56.978.

    Article  CAS  Google Scholar 

  43. Rehm GW, Wiese RA, Hergert GW. Response of corn to zinc source and rate of zinc band applied with either orthophosphate or polyphosphate. Soil Sci. 1980. https://doi.org/10.1097/00010694-198001000-00007.

    Article  Google Scholar 

  44. Riley MM, Robson AD, Gartrell JW, Jeffery RC. The absence of leaching of molybdenum in acidic soils from western Australia. Soil Res. 1987;25(2):179–84.

    Article  CAS  Google Scholar 

  45. Schmoll J, Schimrosczyk B, Ebeling G, Henze J, 2013. Method for solubilizing molybdenum oxide concentrates. Google Patents.

  46. Tang Y, Yang Y, Hou S, Cheng D, Yao Y, Zhang S, Xie J, Wang X, Ma X, Yu Z, Li S. Multifunctional iron-humic acid fertilizer from ball milling double-shelled Fe–N-doped hollow mesoporous carbon microspheres with lignite. ACS Sustain Chem Eng. 2021;9(2):717–31. https://doi.org/10.1021/acssuschemeng.0c06406.

    Article  CAS  Google Scholar 

  47. Tongamp W, Zhang Q, Saito F. Mechanochemical route for synthesizing nitrate form of layered double hydroxide. Powder Technol. 2008;185(1):43–8. https://doi.org/10.1016/j.powtec.2007.09.013.

    Article  CAS  Google Scholar 

  48. Tsuzuki T. Mechanochemical synthesis of metal oxide nanoparticles. Commun Chem. 2021;4(1):143. https://doi.org/10.1038/s42004-021-00582-3.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Umar K, Aris A, Parveen T, Jaafar J, Abdul Majid Z, Vijaya Bhaskar Reddy A, Talib J. Synthesis, characterization of Mo and Mn doped ZnO and their photocatalytic activity for the decolorization of two different chromophoric dyes. Appl Cataly A General. 2015;505:507–14. https://doi.org/10.1016/j.apcata.2015.02.001.

    Article  CAS  Google Scholar 

  50. Walker TW, Adams AFR, Orchiston HD. The effects and interactions of molybdenum, lime and phosphate treatments on the yield and composition of white clover, grown on acid. Molyb Res Soils Plant Soil. 1955;6(2):201–20.

    Article  CAS  Google Scholar 

  51. Wang S, Gao W, Li H, Xiao L-P, Sun R-C, Song G. Selective fragmentation of biorefinery corncob lignin into p-hydroxycinnamic esters with a supported zinc molybdate catalyst. Chemsuschem. 2018;11(13):2114–23. https://doi.org/10.1002/cssc.201800455.

    Article  CAS  PubMed  Google Scholar 

  52. Wang Y, Zhang X, Meng X, Cao Y, Yang F, Nan J, Song Q, Huang Q, Wei C, Zhang J, Zhao Y. Simulation, fabrication, and application of transparent conductive Mo-doped ZnO film in a solar cell. Sol Energy Mater Sol Cells. 2016;145:171–9. https://doi.org/10.1016/j.solmat.2015.09.015.

    Article  CAS  Google Scholar 

  53. Wu M, Yu S, Chen G, He L, Yang L, Zhang W. Structural, optical, and electrical properties of Mo-doped ZnO thin films prepared by magnetron sputtering. Appl Surf Sci. 2015;324:791–6. https://doi.org/10.1016/j.apsusc.2014.11.039.

    Article  CAS  Google Scholar 

  54. Yadav P, Sinha E. Structural, photophysical and microwave dielectric properties of α-ZnMoO4 phosphor. J Alloy Compd. 2019;795:446–52. https://doi.org/10.1016/j.jallcom.2019.05.019.

    Article  CAS  Google Scholar 

  55. Yu C, Yang K, Shu Q, Yu JC, Cao F, Li X, Zhou X. Preparation, characterization and photocatalytic performance of Mo-doped ZnO photocatalysts. Science China Chem. 2012;55(9):1802–10. https://doi.org/10.1007/s11426-012-4721-8.

    Article  CAS  Google Scholar 

  56. Yuan W, Solihin Zhang Q, Kano J, Saito F. Mechanochemical formation of K-Si–Ca–O compound as a slow-release fertilizer. Powder Technol. 2014;260:22–6. https://doi.org/10.1016/j.powtec.2014.03.072.

    Article  CAS  Google Scholar 

  57. Zazhigalov VA, Sachuk EV, Kopachevskaya NS, Bacherikova IV, Wieczorek-Ciurowa K, Shcherbakov SN. Mechanochemical synthesis of nanodispersed compounds in the ZnO-MoO3 system. Theoret Exp Chem. 2016;52(2):97–103. https://doi.org/10.1007/s11237-016-9456-8.

    Article  CAS  Google Scholar 

  58. Zdujić MV, Milošević OB, Karanović LČ. Mechanochemical treatment of ZnO and Al2O3 powders by ball milling. Mater Lett. 1992;13(2):125–9. https://doi.org/10.1016/0167-577X(92)90122-Z.

    Article  Google Scholar 

  59. Zhang JW, He G, Li TS, Liu M, Chen XS, Liu YM, Sun ZQ. Modulation of microstructure and optical properties of Mo-doped ZnO thin films by substrate temperature. Mater Res Bull. 2015;65:7–13. https://doi.org/10.1016/j.materresbull.2015.01.004.

    Article  CAS  Google Scholar 

  60. Zhang Q, Saito F. Mechanochemical synthesis of slow-release fertilizers through incorporation of alumina composition into potassium/ammonium phosphates. j Am Ceram Soc. 2009;92(12):3070–3. https://doi.org/10.1111/j.1551-2916.2009.03291.x.

    Article  CAS  Google Scholar 

  61. Zhao D, Sathasivam S, Li J, Carmalt CJ. Transparent and conductive molybdenum-Doped ZnO thin films via chemical vapor deposition. ACS Appl Electron Mater. 2020;2(1):120–5. https://doi.org/10.1021/acsaelm.9b00647.

    Article  CAS  Google Scholar 

Download references

Acknowledgements

Bo Zheng is grateful for the scholarship and support from The University of Adelaide, School of Agriculture, Food and Wine. We thank the help and support from Adelaide Microscopy and Ken Neubauer for SEM analysis. The authors acknowledge the support of The Mosaic Company LLC. The authors thank Bogumila Tomczak, Ashleigh Panagaris and Andrea Paparella for their advice and technical support.

Author information

Authors and Affiliations

  1. Fertilizer Technology Research Centre, School of Agriculture, Food and Wine, The University of Adelaide, Waite Campus PMB 1, Glen Osmond, Adelaide, SA, 5064, Australia

    Bo Zheng, Fien Degryse, Ivan B. Andelkovic, Roslyn Baird & Mike John McLaughlin

Authors
  1. Bo Zheng
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Fien Degryse
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Ivan B. Andelkovic
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Roslyn Baird
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Mike John McLaughlin
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

BZ, FD, IBA, RB, and MJM contributed to the study conception and design Material preparation, setting up the trial and data collection was performed by BZ. The first draft of the manuscript was written by BZ and all authors commended on previous versions of the manuscript. All authors read and approved the final manuscript.

Corresponding author

Correspondence to Bo Zheng.

Ethics declarations

Ethics approval and consent to participate

Not applicable.

Consent for publication

Not applicable.

Competing interests

The authors declare that they have no competing interests. This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary Information

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Zheng, B., Degryse, F., Andelkovic, I.B. et al. Effect of mechanochemically modified MoO3–ZnO on Mo supply to plants when co-granulated with macronutrient fertilizers. Chem. Biol. Technol. Agric. 11, 115 (2024). https://doi.org/10.1186/s40538-024-00626-5

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doi.org/10.1186/s40538-024-00626-5

Keywords