Sub‐1 nm MoC Quantum Dots Decorating N‐Doped Graphene as Advanced Electrocatalysts of Flexible Hybrid Alkali–Acid Zn‐Quinone Battery. Issue 22 (2nd May 2022)

• Record Type: Journal Article
• Authors: Cai, Pingwei; Li, Junwei; Huang, Junheng; Chen, Junxiang; Ding, Yichun; Peng, Xinxin; Wen, Zhenhai
• Is Part Of: Small. Volume 18:Issue 22(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-05-02
• Subjects: electrocatalysis -- flexible devices -- hybrid alkali–acid Zn‐quinone batteries -- MoC quantum dots; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202201144
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: The development of flexible energy devices is envisaged to revolutionize the next generation of the wearable electronics industry, the practical application yet faces critical issues of low power density, poor cycling stability, and low energy density. Herein, the authors report a newly flexible hybrid Zn‐quinone battery (h‐ZnQB) with acidic gel in the cathode and alkaline gel in the anode, in which proton (H + ) and hydroxide ions (OH – ) are served as the ion charge carriers for acidic quinone cathode and alkaline Zn anode. To this end, the nanohybrids of sub‐1 nm MoC quantum dots decorating nitrogen‐doped ultrathin graphene (MoC QDs/NG) are developed as the advanced cathode electrocatalysts toward redox conversion between quinone and hydroquinone (H2 Q/Q). Comprehensive characterization studies and density functional theory (DFT) calculations reveal that high valent Mo species originating from the size‐effects serve as the active sites for the conversion of H2 Q/Q, contributing to the impressive catalytic performance. The as‐developed flexible h‐ZnQB displays a high open‐circuit voltage of 1.74 V with a specific capacity of 223.3 mAh g –1 and an energy density of 350 Wh kg –1 at 0.2 A g –1, thanks to the fast kinetics of charge carriers (H + and OH – ), the high activity of the catalyst, and the elaborate design of alkali–acid gel electrolytes. Abstract : A flexible hybrid alkali–acid Zn‐quinone battery (h‐ZnQB) is proposed by employing sub‐1 nm MoC quantum dots decorating nitrogen‐doped graphene as cathode catalyst, which displays a favorable performance, thanks to the fast kinetics of charge carriers (H + and OH – ), the high activity of the catalyst, and the elaborate design of alkali–acid gel electrolytes.