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

• 来源期刊: 科学通报（英文版）
• 年，卷（期）: 2019,（1）
• 页码范围: 44-53
• 页数: 10页
• 语种: 英文

摘要

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.