Manipulation of n → π* electronic transitions via implanting thiophene rings into two-dimensional carbon nitride nanosheets for efficient photocatalytic water purification

Authors

Fengting He
Xiaoming Liu
Xiaoli Zhao, Edith Cowan University
Jinqiang Zhang
Pei Dong
Yang Zhang
Chaocheng Zhao
Hongqi Sun, Edith Cowan UniversityFollow
Xiaoguang Duan
Shaobin Wang
Shuaijun Wang

Document Type

Journal Article

Publication Title

Journal of Materials Chemistry A

Publisher

Royal Society of Chemistry

School

School of Engineering

RAS ID

52102

Funders

Australian Research Council

Grant Number

ARC Number : DE210100253

Grant Link

http://purl.org/au-research/grants/arc/DE210100253

Comments

He, F., Liu, X., Zhao, X., Zhang, J., Dong, P., Zhang, Y., ... & Wang, S. (2022). Manipulation of n→ π* electronic transitions via implanting thiophene rings into two-dimensional carbon nitride nanosheets for efficient photocatalytic water purification. Journal of Materials Chemistry A, 10(38), 20559-20570.

https://doi.org/10.1039/d2ta04975a

Abstract

The photocatalytic performance of polymeric carbon nitride (C₃N₄) is heavily restricted by insufficient n → π* electronic transitions and limited active sites. To this end, we adopted an integrated copolymerization and repyrolysis approach to fabricate two-dimensional thiophene ring implanted (C₃N₄) nanosheets (2D Th_ing-CNNS). Advanced characterization studies demonstrated that the fusion of thiophene rings and the formation of 2D nanosheets significantly collectively elevated the n → π* electronic transitions and enlarged the specific surface areas of 2D Th_ing-CNNS, leading to a dramatically extended π-conjugated system and accelerated charge migration. Transmission electron microscopy, X-ray diffraction, and solid-state ¹³C NMR proved the existence of the thiophene ring. Additionally, quantum computations of the highest occupied and lowest unoccupied crystal orbitals implied that the 2D Th_ing-CNNS are more favorable for carrier migration than pristine (C₃N₄). The finite element method (FEM) analysis indicates that 2D Th_ing-CNNS have a stronger surface electric field and radiation absorption, which is consistent with the enhanced n → π* transition. Consequently, 2D Th_ing-CNNS exhibit a 42.7-fold enhancement in photocatalytic performances for bisphenol A oxidation accordingly, compared with pristine C₃N₄. This work provides a novel strategy for engineering the electronic structure of C₃N₄ for highly efficient water purification.

DOI

10.1039/d2ta04975a

Access Rights

subscription content