Atomic carbon chains-mediated carriers transfer over polymeric carbon nitride for efficient photocatalysis

This study demonstrates a novel approach to tailor electronical conductivity of polymeric carbon nitride (CN) by constructing molecule-level carbon chains in the defect-rich layers of CN, whereby the light-induced carriers transfer kinetics is boosted dramatically. [Display omitted] •Well-defined short carbon chains are first reported to link the defects of carbon nitride (CN) through covalent CN bonds in the planar layers at atomic level.•The embedded carbon chains act as smooth electron channel and favor photoinduced charge mobility within the basal plane of CN.•The incorporation of conductive carbon chains in carbon nitride can afford a 13.2 and 29.2-fold enhancement for visible-light-driven H2 evolution and CO2 reduction, respectively. Atomic structure tailoring towards high electron mobility is an essential approach to maximizing the solar energy-conversion efficiency of polymeric carbon nitride (CN) but still presents a significant challenge. Here we construct a smooth carrier channel in the basal plane of CN by filling the rich defects in layer with various kinds of short carbon chains, whereby the light-induced carriers transfer kinetics is boosted distinctly. Consequently, the optimal carbon chains-planted CN delivers a remarkably enhanced photocatalytic performance, achieving a 13.2 and 29.2-fold improvement in H2 evolution and CO2 reduction, respectively. This study provides an in-depth insight into the modulation of in-plane electrical conductivity at molecular scale over CN and offers new opportunities for reinforcing the reaction kinetics of organic-based photocatalysts.