Malaysian Journal of Analytical Sciences Vol 18 No 3 (2014): 522 - 526

 

 

 

Synthesis of Nanocrystalline Olivine LiNiPO₄

Powder Prepared by Sol-Gel Method: Thermal Analysis and XRD Studies

 

(Penyediaan Serbuk Nanokristal LiNiPO₄ dengan Struktur Olivin Melalui Kaedah Sol-Gel: Analisis Terma dan Kajian XRD)

 

Azlin Sanusi^1,2,3*, Shanti Navaratnam^2,3, Wan Jeffrey Basirun⁴

 

¹INTEC Education College,

Jalan Senangin Satu 17/2A, Seksyen 17, 40200 Shah Alam, Selangor, Malaysia

²Faculty of Applied Sciences,

 ³Institue of Science,

Universiti Teknologi Mara,40450 Shah Alam , Selangor Malaysia

⁴Chemistry Department, Faculty of Science,

University of Malaya,50732 Kuala Lumpur, Malaysia

 

*Corresponding author: azlin457@salam.uitm.edu.my

 

 

Abstract

LiMPO₄ have attracted much attention as potential cathode material as it does not liberate oxygen on decomposition unlike lithium transition metal oxides (LMO). In this work, LiNiPO₄  powder was prepared by sol gel method using  LiOH, Ni(CH₃COO)₂, NH₄H₂(PO₄) and  tartaric acid  as chelating agent .The precursor powders were studied by thermogravimetric analysis (TGA). Based on the TGA results, the sample was calcined at 1000^oC in air. The TGA/DTGA studies have been employed to analyse the reaction of raw materials during the formation of LiNiPO₄ .The formation mechanism for the synthesis of LiNiPO₄  and the overall decomposition equation for the precursor were proposed from the TGA/DTGA analysis. The calculated total weight loss from the overall proposed decomposition process which is 66.4% shows agreement with the percentage weight loss from the TGA curves which is 68%.  The X-ray diffraction analysis was carried out to confirm the formation of LiNiPO₄. The precursors and the calcined powders were characterized by X-ray diffraction (XRD). Analysis of the synthesized LiNiPO₄ using XRD demonstrated the formation of a pure LiNiPO₄ phase powder.

 

Keywords: lithium nickel phosphate, sol-gel, mechanism

 

Abstrak

LiMPO₄  telah menarik banyak minat terhadap potensinya sebagai bahah katod untuk bateri litium. kerana tidak seperti  litium oksida logam peralihan (LMO) bahan ini tidak melepaskan oksigen ketika proses penguraian. Didalam kajian ini LiNiPO₄ telah disintisis dengan mencampurkan LiOH, Ni(CH₃COO)₂, NH₄H₂(PO₄) dan asid tartarik  dengan menggunakan kaedah sol-gel. Analisis TGA telah dilakukan keatas prapenanda LiNiPO₄ untuk menetukan suhu pembakaran dan didapati suhu yang sesuai adalah 1000⁰C. Unjuran persamaan bagi penguraian prapenanda LiNiPO₄ telah diperolehi dengan menggunakan lekok TGA/DTGA. Pengiraan peratus penurunan berat menggunakan persamaan unjuran (66.4%) dan lekok TGA (68%) adalah hampir sama. Spektrum belauan sinar –X (XRD) menunjukkan bahan sampel LiNiPO₄ adalah tulin.

 

Kata kunci: litium nikel fosfat, kaedah sol-gel, mekanisme

 

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