Facile synthesis of bimodal macroporous g-C3N4/SnO2 nanohybrids with enhanced photocatalytic activity

Yingzhi Chen; Wenhao Li; Dongjian Jiang; Kuo Men; Zhen Li; Ling Li; Shizheng Sun; Jingyuan Li; Zheng-Hong Huang; Lu-Ning Wang

doi:10.1016/j.scib.2018.12.015

Facile synthesis of bimodal macroporous g-C₃N₄/SnO₂ nanohybrids with enhanced photocatalytic activity

Sci Bull (Beijing). 2019 Jan 15;64(1):44-53. doi: 10.1016/j.scib.2018.12.015. Epub 2018 Dec 15.

Authors

Affiliations

¹ School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China.
² State Key Laboratory of Advanced Materials for Smart Sensing, General Research Institute for Non-Ferrous Metals, Beijing 101407, China.
³ Key Laboratory of Advanced Materials (MOE), School of Materials Science and Engineering, Tsinghua University, Beijing 100084, China. Electronic address: zhhuang@mail.tsinghua.edu.cn.
⁴ School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China; State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China. Electronic address: luning.wang@ustb.edu.cn.

PMID: 36659522
DOI: 10.1016/j.scib.2018.12.015

Abstract

It is of vital importance to construct highly interconnected, macroporous photocatalyst to improve its efficiency and applicability in solar energy conversion and environment remediation. Graphitic-like C₃N₄ (g-C₃N₄), as an analogy to two-dimensional (2D) graphene, is highly identified as a visible-light-responsive polymeric semiconductor. Moreover, the feasibility of g-C₃N₄ in making porous structures has been well established. However, the preparation of macroporous g-C₃N₄ with abundant porous networks and exposure surface, still constitutes a difficulty. To solve it, we report a first facile preparation of bimodal macroporous g-C₃N₄ hybrids with abundant in-plane holes, which is simply enabled by in-situ modification through thermally treating the mixture of thiourea and SnCl₄ (pore modifier) after rotary evaporation. For one hand, the formed in-plane macropores endow the g-C₃N₄ system with plentiful active sites and short, cross-plane diffusion channels that can greatly speed up mass transport and transfer. For another, the heterojunctions founded between g-C₃N₄ and SnO₂ consolidate the electron transfer reaction to greatly reduce the recombination probability. As a consequence, the resulted macroporous g-C₃N₄/SnO₂ nanohybrid had a high specific surface area (SSA) of 44.3 m²/g that was quite comparable to most nano/mesoporous g-C₃N₄ reported. The interconnected porous network also rendered a highly intensified light absorption by strengthening the light penetration. Together with the improved mass transport and electron transfer, the macroporous g-C₃N₄/SnO₂ hybrid exhibited about 2.4-fold increment in the photoactivity compared with pure g-C₃N₄. Additionally, the recyclability of such hybrid could be guaranteed after eight successive uses.

Keywords: Highly macroporous; Interconnected network; Nanohybrid; Photocatalysis; g-C(3)N(4).