Enriching CO₂ Activation Sites on Graphitic Carbon Nitride with Simultaneous Introduction of Electron‐Transfer Promoters for Superior Photocatalytic CO₂‐to‐Fuel Conversion

Abstract

Limited CO 2 adsorption and inefficient charge transfer of graphitic carbon nitride (g‐C 3 N 4 ) have been the two major obstacles for its application in photocatalytic CO 2 reduction. In this work, a new type of carbon nitride photocatalyst (K‐incorporated amino‐rich carbon nitride, K‐AUCN) is designed and prepared by a facile posttreatment of urea‐polymerized g‐C 3 N 4 (UCN) using KOH as a chemical activation agent. The resultant K‐AUCN has not only enriched intrinsic amino groups for superior CO 2 adsorption, but also incorporated potassium and carbon defects as electron promoters for efficient photocatalytic reduction of CO 2 in the presence of water vapor. Compared to UCN, the photocatalytic CO 2 conversion performance on K‐AUCN is drastically promoted by five folds with 7.7‐time increase in CO 2 adsorption. This work not only presents a simple design of low‐cost photocatalyst for CO 2 reduction with enhanced performance, but shall also inspire more rational design of efficient catalysts for photocatalytic reduction of CO 2 and other specific photocatalytic reactions.