(浙江大學 化學系,杭州 310027)
摘 要: 通過一種新穎的脫合金方法制備厚度為5 μm、平均孔徑為200~300 nm的三維納米多孔銅膜,制備過程涉及銅基體上鍍鋅層的熱處理與酸浸過程。以三維納米多孔銅膜為基體,采用陰極電沉積法制備納米多孔結(jié)構(gòu)的錫膜電極。應用掃描電子顯微鏡(SEM)、X線衍射分析(XRD)和恒流充放電方法對所制備的膜電極的結(jié)構(gòu)與電化學性能進行表征。所制備的多孔錫電極在0.1 C率下的首次充放電中的可逆儲鋰容量為864 mA×h/g,該容量已接近錫的理論容量(993 mA?h/g);在50次充放電循環(huán)后,可逆容量仍有541 mA×h/g。納米多孔結(jié)構(gòu)、納米尺度的錫顆粒及高電子導電性的三維納米多孔銅膜基體等因素是多孔錫電極顯示較好儲鋰性能的主要原因。
關(guān)鍵字: 鋰離子電池;錫;多孔銅;納米多孔結(jié)構(gòu);負極
(Department of Chemistry, Zhejiang University, Hangzhou 310027, China)
Abstract:A three-dimensional (3D) nanoporous copper film with thickness of 5 μm and average pore diameter of 200-300 nm was fabricated by novel dealloying method. The fabrication process involves the heat treatment of the electrodeposited zinc layer on copper substrate and the subsequent acidic leaching of the annealed film. A porous nanostructured tin film electrode was further prepared by the cathodic electrodeposition of tin film on the obtained 3D nanoporous copper film, and its structure and electrochemical properties were investigated by scanning electron microscopy (SEM), X-ray diffractometry (XRD) and galvanostatic charge-discharge tests. The as-prepared porous tin electrode presents an initial reversible lithium storage capacity of 864 mA×h/g at 0.1C, closing to the theoretical capacity of Sn (993 mA×h/g). And it still delivers a reversible capacity of 541 mA×h/g after 50 cycles. The nanoporous structure, nanosized tin particles and 3D porous copper substrate with high electronic conductivity can be responsible for the enhanced lithium storage performance of the porous tin electrode.
Key words: lithium ion batteries; tin; porous copper; nanoporous structure; negative electrode


