کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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1332228 | 979034 | 2011 | 6 صفحه PDF | دانلود رایگان |
The nitrate-form of Ca–Fe-layered double hydroxide (Ca–Fe-LDH) was synthesized via co-precipitation method, and its phosphate-intercalates were prepared by ion-exchange reaction. According to X-ray diffraction analysis, the Ca–Fe-LDH–NO3− compound and its H2PO4−-intercalate showed hexagonal layered structures, whereas the ion-exchange reaction with HPO42− caused a frustration of the layer ordering of LDH. Fe K-edge X-ray absorption spectroscopy clearly demonstrated that the Ca–Fe-LDH lattice with trivalent iron ions was well-maintained after the ion-exchange with HPO42− and H2PO4−. Under acidic conditions, phosphate ions were slowly released from the Ca–Fe-LDH lattice and the simultaneous release of hydroxide caused the neutralization of acidic media. Fitting analysis based on kinetic models indicated a heterogeneous diffusion process of phosphates and a distinct dependence of release rate on the charge of phosphates. This study strongly suggested that Ca–Fe-LDH is applicable as bifunctional vector for slow release of phosphate fertilizer and for the neutralization of acid soil.
We synthesized phosphate-intercalated Ca–Fe-LDH materials that can act as bifunctional inorganic vectors for the slow release of phosphate fertilizer and also the neutralization of acid soil. Fitting analysis based on kinetic models indicated a heterogeneous diffusion process of phosphates and a distinct dependence of release rate on the charge of phosphates.Figure optionsDownload as PowerPoint slideResearch Highlights
► The phosphate forms of Ca–Fe-layered double hydroxide (Ca–Fe-LDH) were synthesized via co-precipitation method. The crystal structure, bonding character, and release kinetics of phosphate of the phosphate-intercalates were investigated. These Ca–Fe-LDH materials are applicable as bifunctional vector for slow release of phosphate fertilizer and for the neutralization of acid soil.
Journal: Journal of Solid State Chemistry - Volume 184, Issue 1, January 2011, Pages 171–176