碳包覆多孔硅镍合金负极的制备与电化学性能研究

Study on Preparation and Electrochemical Performance of Carbon-coated Porous Silicon-Nickel Alloy Anode

基于铸造Ni_(53)Si_(47)合金,采用去合金化与溶胶-凝胶热解方法,成功制备出碳包覆多孔硅镍合金负极。采用XRD、SEM、EDS、XRF手段表征了碳包覆多孔硅镍合金负极的物相构成、微观结构与化学成分,并对其电化学性能进行了研究。结果显示,该负极具有典型的纳米多孔结构,且碳包覆层均匀完整。该负极在0.1mA/g的电流密度下具有1156.80/2243.82mA·h/g的首次充电/放电比容量,并在60周循环后仍具有771.20mA·h/g的可逆比容量与66.67%的容量保持率,展现出优良的循环稳定性。

The carbon-coated porous silicon-nickel alloy anode was successfully prepared based on as-cast Ni_(53)Si_(47) alloy by using dealloying and sol-gel pyrolysis methods.The crystalline phases,microstructure and chemical composition of the carbon-coated porous silicon-nickel alloy anode were characterized by XRD,SEM,EDS and XRF,and the electrochemical properties were investigated.The results show that the carbon-coated porous silicon-nickel alloy anode exhibits typical nanoporous structure with uniformly coated carbon layer.It displays initial charge/discharge specific capacity of 1156.80/2243.82 mA·h/g at current density of 0.1 mA/g,and it operates steadily with reversible specific capacity of 771.20mA·h/g and capacity retention rate of 66.67% after 60 cycles and demonstrates excellent cycling stability.