Surface modification to control the secondary pollution of photocatalytic nitric oxide removal over monolithic protonated g-C3N4/graphene oxide aerogel

Ruiyang Zhang; Aili Zhang; Ye Yang; Yuehan Cao; Fan Dong; Ying Zhou

doi:10.1016/j.jhazmat.2020.122822

Surface modification to control the secondary pollution of photocatalytic nitric oxide removal over monolithic protonated g-C₃N₄/graphene oxide aerogel

J Hazard Mater. 2020 Oct 5:397:122822. doi: 10.1016/j.jhazmat.2020.122822. Epub 2020 May 12.

Authors

Ruiyang Zhang¹, Aili Zhang¹, Ye Yang², Yuehan Cao², Fan Dong³, Ying Zhou⁴

Affiliations

¹ State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China; The Center of New Energy Materials and Technology, School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China.
² The Center of New Energy Materials and Technology, School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China.
³ Research Center for Environmental Science & Technology, Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China, Chengdu 611731, China.
⁴ State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, Southwest Petroleum University, Chengdu 610500, China; The Center of New Energy Materials and Technology, School of New Energy and Materials, Southwest Petroleum University, Chengdu 610500, China. Electronic address: yzhou@swpu.edu.cn.

PMID: 32442853
DOI: 10.1016/j.jhazmat.2020.122822

Abstract

Recently, photocatalytic NO_x treatment has attracted great attention on account of the use of environmental-friendly and tremendous energy source. However, the difficult recovery of most reported powdery photocatalysts and the high generation rate of toxic NO₂ byproduct limit its application. Here, we designed a novel monolithic protonated g-C₃N₄/graphene oxide aerogel through a direct frozen-drying method. A remarkable surface electric charge change of negative g-C₃N₄ to positive protonated g-C₃N₄ can be observed after the protonating treatment, which connects with negative graphene oxide nanosheets through the formation of strong electrostatic self-assembly to accelerate the photogenerated charge carriers transfer. Graphene oxide aerogel acts as a monolithic substrate, which provides abundant porous structure, enhanced visible-light absorption, and electrons transport pathway to improve photocatalytic activity. Importantly, the introduction of H atoms on the N atoms of p-C₃N₄ promotes the activation of oxygen atoms, thus improving the oxidization of NO₂ to nitrate. As a result, protonated g-C₃N₄/graphene oxide aerogel reveals an excellent NO removal ratio (46.1%) and low NO₂ generation (2.4%), demonstrating its excellent promising for air pollution purification. Our current work affords novel innovative insight for the construction of monolithic photocatalysts to control the secondary pollution for environmental remediation.

Keywords: Nitric oxide oxidization; Photocatalysis; Protonated g-C(3)N(4)/graphene oxide aerogel; Secondary pollution control; Surface modification.

Publication types

Research Support, Non-U.S. Gov't