Heteroelement Y-doped α-Ni(OH)2 nanosheets with excellent pseudocapacitive performanceElectronic supplementary information (ESI) available: ESR measurement of YNi-0 and YNi-2. BET analysis of YNi-0, YNi-1, YNi-2 and YNi-3. SEM images of YNi-0, YNi-1, YNi-2 and YNi-3. EDX analyses of YNi-1, YNi-2 and YNi-3. Electrochemical performance of YNi-0, YNi-1 and YNi-3. DFT calculations of pure α-Ni(OH)2 and 33% Y-doped α-Ni(OH)2. See DOI: 10.1039/c7ta00963a

• Main Authors: Zhang, Yao, Zhao, Yufei, An, Weidan, Xing, Li, Gao, Yanfang, Liu, Jinrong
• Format: Journal Article
• Language: English
• Published: 23.05.2017
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/c7ta00963a

Doping is an efficient method to promote the electronic conductivity and improve the capacitive performance of electrodes for further energy conversion. Herein, by doping heteroelement metal ions, an ultrathin Y (yttrium)-doped α-Ni(OH) 2 nanosheet electrode with a large surface area and hierarchical porous structure is fabricated via a facile approach. The Y-doped α-Ni(OH) 2 nanosheets exhibit a high specific capacitance of 1860 F g −1 at a current density of 1 A g −1 mainly due to the increased electronic conductivity of the increased Ni 3+ species, as evidenced by density functional theory calculations. As a result, the asymmetric supercapacitor device based on the Y-doped α-Ni(OH) 2 nanosheet electrode demonstrates both a remarkably high energy density (58.4 W h kg −1 ) and power density (754.56 W kg −1 ). High-conductivity Y (yttrium) doped α-Ni(OH) 2 nanosheets hold great potential for assembling high-performance energy storage devices.