posted on 2017-06-12, 00:00authored byZengxia Pei, Jingxing Gu, Yukun Wang, Zijie Tang, Zhuoxin Liu, Yan Huang, Yang Huang, Jingxiang Zhao, Zhongfang Chen, Chunyi Zhi
Atomically
precise understanding of componential influences is
crucial for looking into the reaction mechanism and controlled synthesis
of efficient electrocatalysts. Herein, by means of comprehensive experimental
and theoretical studies, we carefully examine the effects of component
dopants on the catalytic performance of graphitic C3N4 (g-C3N4)-based electrocatalysts. The
g-C3N4 monoliths with three types of dopant
elements (B, P, and S) embedded in different sites (either C or N)
of the C–N skeleton are rationally designed and synthesized.
The kinetics, intrinsic activity, charge-transfer process, and intermediate
adsorption/desorption free energy of the selected catalysts in oxygen
reduction reaction and hydrogen evolution reaction are investigated
both experimentally and theoretically. We demonstrate that the component
aspect within the g-C3N4 motifs has distinct
and substantial effects on the corresponding electroactivities, and
proper component element engineering can be a viable yet efficient
protocol to render the metal-free composites as competent catalysts
rivaling the metallic counterparts. We hope that this study may shed
light on the empirical trial-and-error exploration in design and development
of g-C3N4-based materials as well as other metal-free
catalysts for energy-related electrocatalytic reactions.