Design of Aligned Porous Carbon Films with Single‐Atom Co–N–C Sites for High‐Current‐Density Hydrogen Generation. Issue 41 (23rd August 2021)

• Record Type: Journal Article
• Authors: Liu, Rui; Gong, Zhichao; Liu, Jianbin; Dong, Juncai; Liao, Jiangwen; Liu, Huan; Huang, Haikang; Liu, Jingjing; Yan, Minmin; Huang, Kang; Gong, Haisheng; Zhu, Jian; Cui, Chunyu; Ye, Gonglan; Fei, Huilong
• Is Part Of: Advanced materials. Volume 33:Issue 41(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2021-08-23
• Subjects: electrocatalysis -- graphene -- high current density -- hydrogen evolution reaction -- porous films -- single‐atom catalysts; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.202103533
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: Metal‐ and nitrogen‐doped carbon (M–N–C) materials as a unique class of single‐atom catalysts (SACs) have increasingly attracted attention as the replacement of platinum for the hydrogen evolution reaction (HER); however, their employment as HER electrodes at high current densities of industrial level remains a grand challenge. Herein, an aligned porous carbon film embedded with single‐atom Co–N–C sites of exceptional activity and stability at high current densities is designed. Within the film, the atomic CoN x moieties exhibit high intrinsic activity, while the multiscale porosity of the carbon frameworks with vertically aligned microchannels afford facilitated mass transfer under the conditions of high production rate and ultrathick electrodes. Moreover, the superwetting properties of the film promote electrolyte wetting and ensure the timely removal of the evolving H2 gas bubbles. The as‐designed film can work as an efficient HER electrode to deliver 500 and 1000 mA cm −2 in acid at overpotentials of 272 and 343 mV, respectively, and can operate uninterruptedly and stably at 1000 mA cm −2 for at least 32 h under static conditions. These findings pave the road toward the rational design of SACs with improved activity and stability at high current densities in gas‐evolving electrocatalytic processes. Abstract : A film electrode consisting of atomic Co–N–C sites dispersed on vertically aligned porous nanocarbon is designed, with merits of high intrinsic activity, enriched number of active sites, and efficient mass transport of both the liquid reactant and the gaseous product, enabling it to be used for high‐current‐density hydrogen generation with high activity and stability.