Bridging Functional Groups Governing the Charge Transfer Dynamic in an Amorphous Carbon Nitride Allotropic Heterojunction toward Efficient Solar Hydrogen Evolution. Issue 1 (23rd November 2020)

• Record Type: Journal Article
• Authors: Huang, Kuan-Hsiang; Hou, Sheng-Shu; Wu, Jih-Jen
• Is Part Of: Solar RRL. Volume 5:Issue 1(2021)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-11-23
• Subjects: allotropic heterojunctions -- amorphous carbon nitrides -- bridging functional groups -- charge transfer dynamic -- photocatalytic hydrogen evolution; Solar energy -- Periodicals; Photovoltaic power generation -- Periodicals; Solar energy -- Research -- Periodicals; Photovoltaic power generation -- Research -- Periodicals; Periodicals; 333.7923
• DOI: 10.1002/solr.202000496
• Languages: English
• ISSNs: 2367-198X

Abstract

Abstract : Modulation of the charge transfer dynamic in amorphous carbon nitride allotropic heterojunctions by an alternation in bridging functional groups for the heptazine‐ and triazine‐based fragments is demonstrated to boost the photocatalytic activity for hydrogen evolution. Pyrimidine‐bridged and NH‐bridged amorphous carbon nitride allotropic heterojunctions are synthesized by thermal polycondensation of a supramolecular complex. Due to the improved charge separation efficiency and visible‐light harvesting ability, both allotropic heterojunctions present more than tenfold enhanced photocatalytic activities for hydrogen evolution compared to the conventional heptazine‐based carbon nitride under visible‐light illumination. Moreover, the photocatalytic activity of the NH‐bridged carbon nitride allotropic heterojunction with type‐II charge transfer dynamic is superior to the pyrimidine‐bridged one with a Z‐scheme characteristic. The findings in this study emphasize that the electronic structure at the heterojunction interface governed by the bridging group greatly influences the charge transfer dynamic and therefore is a crucial factor driving the photocatalytic activity of carbon nitride allotropic heterojunctions. Abstract : Charge transfer dynamics governing the photocatalytic activity in amorphous carbon nitride allotropic heterojunctions can be regulated by the bridge function groups through alternating of the electronic structures. The type‐II carbon nitride allotropic heterojunction bridged by NH groups exhibits a higher hydrogen evolution rate compared to the Z‐scheme one bridged by pyrimidine rings.