Modification of Si anode with various coating matrixes is a promising strategy to resolve the unsta-ble solid electrolyte interphase issues.However,the com-plex preparation process and inherently weak interaction betw...Modification of Si anode with various coating matrixes is a promising strategy to resolve the unsta-ble solid electrolyte interphase issues.However,the com-plex preparation process and inherently weak interaction between Si and other matrixes impede its practical appli-cation.Inspired by the metallurgical process of aluminum,an aluminosilicate matrix was prepared as coating layer on the surface of Si nanoparticles after heat treatment.Si nanoparticles with a uniform native oxide layer were used as seed crystals for the adsorption of aluminum hydroxide.The strong symbiosis and bond between alumina and silica,such as mullite(3Al_(2)O_(3)·2SiO_(2))or kaolin(Al2O_(3)·SiO_(2)·2H_(2)O),provide homogeneous and durable contact coating layer.The as-produced Si/SiO_(2)·Al_(2)O_(3)composite delivers a charge capacity of 1440 mAh·g^(-1)at 100 mA·g^(-1)and remains 879 mAh·g^(-1)at 3 A·g^(-1).After 200 cycles,the capacity retention remains high at 76%.The enhanced properties were ascribed to SiO_(2)·Al_(2)O_(3)syner-gistic composite coating layer,which could hinder the interfacial side chemical reaction and buffer volume change of Si.展开更多
基金financially supported by the National Natural Science Foundation of China (Nos.52004103, 51974137 and 51774150)China Postdoctoral Science Foundation (No.2020M671361)Jiangsu Postdoctoral Science Foundation (No.2020Z090)
文摘Modification of Si anode with various coating matrixes is a promising strategy to resolve the unsta-ble solid electrolyte interphase issues.However,the com-plex preparation process and inherently weak interaction between Si and other matrixes impede its practical appli-cation.Inspired by the metallurgical process of aluminum,an aluminosilicate matrix was prepared as coating layer on the surface of Si nanoparticles after heat treatment.Si nanoparticles with a uniform native oxide layer were used as seed crystals for the adsorption of aluminum hydroxide.The strong symbiosis and bond between alumina and silica,such as mullite(3Al_(2)O_(3)·2SiO_(2))or kaolin(Al2O_(3)·SiO_(2)·2H_(2)O),provide homogeneous and durable contact coating layer.The as-produced Si/SiO_(2)·Al_(2)O_(3)composite delivers a charge capacity of 1440 mAh·g^(-1)at 100 mA·g^(-1)and remains 879 mAh·g^(-1)at 3 A·g^(-1).After 200 cycles,the capacity retention remains high at 76%.The enhanced properties were ascribed to SiO_(2)·Al_(2)O_(3)syner-gistic composite coating layer,which could hinder the interfacial side chemical reaction and buffer volume change of Si.
