Ni(OH)_(2)负极材料的十二烷基硫酸钠辅助制备及其储锂性能

Lithium Ions Storage Properties of Ni(OH)_(2) Anode Materials Prepared with Sodium Dodecyl Sulfate as Accessory Ingredient

以十二烷基硫酸钠(SDS)为辅助剂用均相沉淀法制备出具有微/纳分级结构的α-Ni(OH)_(2)材料并使用XRD、SEM、FT-IR、TGA和XPS等手段进行表征,研究了SDS对其结构和储锂性能的影响。结果表明,在制备过程中使用SDS可细化α-Ni(OH)_(2)的晶粒并有助于形成更加开放的微/纳米分级形貌;在n(SDS)/n(Ni^(2+))为2∶10的条件下制备的α-Ni(OH)_(2)储锂性能最佳,在2 A·g^(-1)电流密度下循环40次后其比容量保持在800 mAh·g^(-1),在3 A·g^(-1)大电流密度下其可逆比容量仍达到710 mAh·g^(-1),还表现出显著的赝电容效应(在0.9 mV·s^(-1)下其赝电容贡献率高达84.2%)。

α-Ni(OH)_(2) materials with micro/nano hierarchical structure were prepared by a facile homogeneous precipitation method with sodium dodecyl sulfate(SDS)as accessory ingredient.It was found that the introduction of SDS can refine the grain size ofα-Ni(OH)_(2) and facilitate the formation of micro/nano hierarchical morphology with a more open structure as evidenced by XRD,SEM,FT-IR,TGA,and XPS analysis.Results of electrochemical test demonstrate that theα-Ni(OH)_(2) sample synthesized with the n(SDS)/n(Ni^(2+))of 2∶10 exhibits the best lithium ions storage performance.After 40 cycles at the current density of 2 A·g^(-1) theα-Ni(OH)_(2) sample maintained a specific capacity of 800 mAh·g^(-1);even at the high current density of 3 A·g^(-1) it still delivered a reversible specific capacity of 710 mAh·g^(-1).Moreover,it shows a significant pseudo-capacitive effect during discharge/charge processes(the pseudo-capacitive contribution to the total stored charge is as high as 84.2%at 0.9 mV·s^(-1)).