文献类型：期刊文献

英文题名：Designed formation of NiCo2O4 with different morphologies self-assembled from nanoparticles for asymmetric supercapacitors and electrocatalysts for oxygen evolution reaction

作者：Fu, Haihai[1];Liu, Yi[2];Chen, Long[1];Shi, Yulin[1];Kong, Wenwen[3];Hou, Juan[1];Yu, Feng[1];Wei, Tingting[1];Wang, Hao[1];Guo, Xuhong[1,4]

机构：[1]Shihezi Univ, Sch Chem & Chem Engn, Key Lab Green Proc Chem Engn Xinjiang Bingtuan, Shihezi 832003, Peoples R China;[2]Tech Univ, Inst Chem, AG Elektrochem, D-09111 Chemnitz, Germany;[3]Chinese Acad Sci, Xinjiang Tech Inst Phys & Chem, Key Lab Funct Mat & Devices Special Environm, Urumqi 830011, Peoples R China;[4]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2019

卷号：296

起止页码：719

外文期刊名：ELECTROCHIMICA ACTA

收录：;EI(收录号：20190106333386);WOS:【SCI-EXPANDED(收录号:WOS:000454822400081)】；

基金：This work was supported by the Natural Science Foundation of China (21467024, 21661027 and 51764049), the Project-sponsored by Scientific Research Start-up Fund for High-Level Talents, Shihezi University (KX0138), and the Opening Project of The Key Laboratory for Green Processing of Chemical Engineering of Xinjiang Bingtuan (KF201704).

语种：英文

外文关键词：NiCo2O4; Morphology; Asymmetric supercapacitor; Oxygen evolution reaction

摘要：Spinel NiCo2O4 (NCO) as a promising electrode material, is essential for supercapacitors and electrocatalysts for oxygen evolution reaction (OER), which crucially related to its structure and morphology. Herein, hierarchical spinel NCO nanomaterials with different morphologies such as homogeneous NCO nanoparticles, one-dimensional NCO nanorods, heterogeneous NCO nanoflowers, and three-dimensional NCO microspheres assembled with nanoparticles are synthesized via facile coprecipitation method combined with calcination process. The effect of precipitating agents on designed formation mechanism of these NCO structures is further investigated. NCO microspheres are evaluated as supercapacitors and demonstrate excellent electrochemical performances with a high specific capacitance (225.07 C/g at 0.5 A/g) and cycling stability (86.9% at 2 A/g over 3000 cycles). Furthermore, the asymmetric supercapacitor is fabricated with NCO microspheres as the positive and graphene as the negative respectively, which exhibits a high energy density of 19.12 Wh/kg at a power density of 509.87 W/kg. As the electrocatalyst, NCO microspheres also show a superior OER electrocatalytic activity with a minimal Tafel slope of 70.32 mV dec(-1) due to more mesoporous and diffusion pathways than other NCO samples. These results provide a new strategy to develop affordable alternative OER catalysts and asymmetric supercapacitors. (C) 2018 Elsevier Ltd. All rights reserved.