Effects of pH on Preparation and Properties of CaTi₂O₄(OH)₂ by Hydrothermal Method

Abstract:

A novel CaTi₂O₄(OH)₂ nanosheet was synthesized using anhydrous calcium chloride, lithium chloride and butyl titanate as the basic raw material by a template-free and surfactant-free hydrothermal method. The crystal structure, morphology and element synthesis were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) equipped with an EDS system. Effects of pH on the structure, morphology and electrochemical properties were investigated. The results showed that when pH was 6.7, CaTi₂O₅ phase was obtained. When pH was 8.3, pure CaTi₂O₄(OH)₂ nanosheets were obtained. Further increasing pH to 8.6, CaTi₂O₄(OH)₂ was obtained, however, and CaTiO₃ phase also appeared. When pH was 8.3, the rate capacity of CaTi₂O₄(OH)₂ nanosheets was further higher than those of the samples prepared for pH=6.7 and pH=8.6. It indicated that CaTi₂O₄(OH)₂ nanosheets were helpful for lithium insertion and de-intercalation. The sample synthesized at pH=8.3 showed the best electrochemical performances, with first discharge specific capacity of 177.9 mAh/g at 0.1C rate. The CaTi₂O₄(OH)₂ nanosheets might represent an opportunity for the applications in lithium ion battery.

• Periodical: Key Engineering Materials (Volumes 602-603)
• Pages: 15-18
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.602-603.15
• Online since: March 2014
• Authors: Wei Xia Dong, Gao Ling Zhao, Xing Yong Gu, Bin Song, Gao Rong Han
• Keywords: CaTi₂O₄(OH)₂ Nanosheet, Electrochemical Performance, Hydrothermal Method, pH

References

[1] W. Dong, B. Song, G. Zhao and G. Han. Effects of pH on morphosynthesis and properties of calcium titanium oxides via a facile aqueous strategy. Mater. Res. Bull., 48 (2013) 4633-4640.

DOI: 10.1016/j.materresbull.2013.06.036

[2] W. Dong, B. Song, G. Zhao and G. Han. Synthesis and characterization of CaTi2O4(OH)2 nanosheets for lithium-ion battery. Int. J. Electrochem. Sc., 8 (2013) 4551-4559.

[3] W. Dong, B. Song, G. Zhao, and G. Han. Controllable synthesis of CaTi2O4(OH)2 nanoflakes by a facile template-free process and its properties. Ceram. Int., 39 (2013) 6795-6803.

DOI: 10.1016/j.ceramint.2013.02.010

[4] Y. J. Huang, M. C. Tsai, H. T. Chiu, H. S. Sheu, C. Y. Lee, Artificial Synthesis of Platelet-Like Kassite and Its Transformation to CaTiO3, Crystal Growt Design, 10 (2010) 1221–1225.

DOI: 10.1021/cg901204x

[5] M. P. Agnieszka, V. G. Cathie and F. Elzbieta, Carbon/layered double hydroxide (LDH) composites for supercapacitor application, Energy Fuels, 24 (2010) 3346-3351.

DOI: 10.1021/ef901505c