High‐Performance Ytterbium‐Doped V<sub>2</sub>O<sub>5</sub> ⋅ H<sub>2</sub>O Binder‐Free Thin‐Film Electrodes for Supercapacitors
Shu Yang, Yuan Cen, Bingbing Hu, Chuanlan Xu, Yan Li, Jingjing Yu, Bihao Hu, Jiazhi Meng, Danmei Yu, Changguo Chen
Abstract
Abstract In this work, honeycomb‐like Yb‐doped V 2 O 5 ⋅ nH 2 O binder‐free thin film electrodes are synthesized via a simple and convenient sol‐gel method. Benefiting from the synergy of V 2 O 5 ⋅ nH 2 O and rare‐earth metal ion Yb 3+ , thin‐layer honeycomb‐like morphology formed upon the introduction of Yb 3+ into the V 2 O 5 ⋅ nH 2 O, which markedly promotes the electrochemical performance of the V 2 O 5 ⋅ H 2 O thin‐film electrode. After the condition optimization, 8 % Yb−V 2 O 5 ⋅ H 2 O exhibits superior electrochemical performance with a specific capacitance of 703 F g −1 (at 1 A g −1 ) and outstanding cycling stability. Besides, owing to the ultra‐high conductivity of oxide super‐P (OSP) nanoparticles, the V 2 O 5 ⋅ H 2 O@OSP‐4 binder‐free film electrode shows a high specific capacitance of 627 F g −1 , which was prepared by the same simple sol‐gel strategy. The assembled 8 % Yb−V 2 O 5 ⋅ nH 2 O//V 2 O 5 ⋅ nH 2 O@OSP‐4 device delivers a high specific energy density and excellent cycling stability. This study may have certain inspirations for the fabrication of thin‐film electrodes for high‐efficiency energy storage systems.