High mass loading NiCo_(2)O_(4) with shell-nanosheet/core-nanocage hierarchical structure for high-rate solid-state hybrid supercapacitors

作     者：Wang Yang Liqiang Hou Peng Wang Yun Li Rui Li Bo Jiang Fan Yang Yongfeng Li Wang Yang;Liqiang Hou;Peng Wang;Yun Li;Rui Li;Bo Jiang;Fan Yang;Yongfeng Li

作者机构：State Key Laboratory of Heavy Oil ProcessingChina University of Petroleum(Beijing)Changping102249China 

出 版 物：《Green Energy & Environment》 (绿色能源与环境（英文版）)

年 卷 期：2022年第7卷第4期

页      面：723-733页

核心收录：

学科分类：080801[工学-电机与电器] 0808[工学-电气工程] 07[理学] 070205[理学-凝聚态物理] 08[工学] 080501[工学-材料物理与化学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0702[理学-物理学] 

基　　金：financial support from the National Natural Science Foundation of China (Nos.21908245 and 21776308) Science Foundation of China University of Petroleum,Beijing (No. 2462018YJRC009) China Postdoctoral Science Foundation (No. 2018T110187) 

主　　题：Transition-metal oxides Hierarchical structure High mass loading Free-standing Supercapacitors 

摘      要：Rational design of advanced structure for transition metal oxides(TMOs) is attractive for achieving high-performance ***, it is hampered by sluggish reaction kinetics, low mass loading, and volume change upon cycling. Herein, hierarchical Ni Co_(2)O_(4) architectures with 2D-nanosheets-shell and 3D-nanocages-core(2D/3D h-NCO) are directly assembled on nickel foam via a facile one-step *** 2D nanosheets are in-situ generated from the self-evolution of initial NCO nanospheres. This 2D/3D hierarchical structures ensure fast ion/electron transport and maintain the structural integrity to buffer the volume expansion. The 2D/3D h-NCO electrode with an ultrahigh mass loading(30 mg cm^(-2)) achieves a high areal capacity of 4.65 C cm^(-2)(equivalent to 1.29 mAh cm^(-2)) at a current density of 4 mA cm^(-2), and retains 3.7 C cm^(-2) even at 50 mA cm^(-2). Furthermore, the assembled solid-state hybrid supercapacitor yields a high volumetric energy density of 4.25 mWh cm^(-3) at a power density of 39.3 mW cm^(-3), with a high capacity retention of 92.4% after 5000 cycles. Therefore, this work provides a new insight to constuct hierarchical electrodes for energy storage application.