Enhancing Li‐Ion Affinity of Molybdenum Dioxide/Carbon Fabric to Achieve High Pseudocapacitance. Issue 46 (11th October 2021)

• Record Type: Journal Article
• Authors: Liu, Qiyu; Zhang, Haozhe; Yang, Fan; Geng, Hongbo; Liu, Xiaoqing; Yu, Yanxia; Lu, Xihong
• Is Part Of: Small. Volume 17:Issue 46(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-10-11
• Subjects: flexible devices -- high energy -- Li‐ion adsorption -- Li‐ion diffusion -- pseudocapacitors; Nanotechnology -- Periodicals; Nanoparticles -- Periodicals; Microtechnology -- Periodicals; 620.5
• DOI: 10.1002/smll.202104178
• Languages: English
• ISSNs: 1613-6810

Abstract

Abstract: High‐energy electrodes at high mass loadings (usually >8.0 mg cm −2 ) are desired for aqueous pseudocapacitors. Yet, how to overcome the thickness‐dependent resistance increase of ion/electron transport in pseudocapacitive materials is still challenging. Herein, a high‐performance electrode (denoted as AMC) adapted to high mass loading is achieved by promoting the Li‐ion affinity of 3D MoO2 /carbon fabric. The experimental results and corresponding computational results reveal that the oxygen‐activated surface of AMC, combined with the wettability and conductivity superiority of 3D graphite network, significantly facilitates the Li‐ion adsorption and diffusion at the electrode/electrolyte interface, even at large thicknesses. Consequently, even at a high mass loading up to 8.1 mg cm −2, the AMC electrode also displays an impressive specific capacity (567.5 C g −1 at 2.5 A g −1 ), substantially superior to most advanced pseudocapacitive electrodes. The strategy of boosting energy characteristic by enhancing the affinity of charge carriers is applicable to other pseudocapacitive electrodes. Abstract : An advanced 3D MoO2 /carbon negative electrode with high mass loading (8.1 mg cm −2 ) is demonstrated by facilitating the Li‐ion adsorption and diffusion at the interface via surface activation. The as‐fabricated electrode displays desirable specific capacity of 567.5 C g −1 (4.5 C cm −2 ) at 2.5 A g −1 and ultrahigh rate performance (retains 74.0% at 7.5 A g −1 ).