BN诱导BiOI富氧{110}面的暴露并增强其可见光催化氧化性能

1. 1 西南石油大学，油气藏地质及开发工程国家重点实验室，成都 610500
2 西南石油大学，新能源与材料学院，新能源材料及技术研究中心，成都 610500
• 收稿日期:2020-09-21 录用日期:2020-10-23 发布日期:2020-11-02
• 通讯作者: 周莹 E-mail:yzhou@swpu.edu.cn
• 作者简介:第一联系人：

These authors contributed equally to this work.

• 基金资助:
国家自然科学基金(U1862111);四川省科技计划(2020ZDZX0008);成都市国际科技合作项目(2017-GH02-00014-HZ);西南石油大学第十九期(2019-2020学年)大学生课外开放实验重点项目(KSZ19516)

Selective Exposure of BiOI Oxygen-Rich {110} Facet Induced by BN Nanosheets for Enhanced Photocatalytic Oxidation Performance

Qian Zheng1,2, Yuehan Cao2, Nanjian Huang2, Ruiyang Zhang2, Ying Zhou1,2,*()

1. 1 State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation, 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
• Received:2020-09-21 Accepted:2020-10-23 Published:2020-11-02
• Contact: Ying Zhou E-mail:yzhou@swpu.edu.cn
• About author:Ying Zhou, Email: yzhou@swpu.edu.cn; Tel.: +86-28-83037401
• Supported by:
the National Natural Science Foundation of China(U1862111);Sichuan Science and Technology Program, China(2020ZDZX0008);International Collaboration Project of Chengdu City, China(2017-GH02-00014-HZ);College Students' Extracur-Ricular Open Experiment Project of SWPU, China(KSZ19516)

Abstract:

Photocatalytic oxidation is a promising technology for governing emission of environmental pollutants and managing energy crisis. Typically, the photocatalytic performance of photocatalysts is highly dependent on the type of exposed crystal surfaces. As a semiconductor oxide photocatalyst, the different exposed crystal surfaces of bismuth oxyiodide (BiOI) exhibit different photocatalytic oxidation performances. In this study, we chose BiOI as the model material and provided a novel method to improve the photocatalytic oxidation performance by regulating the main exposed crystal facets. Using boron nitride (BN) nanosheets as the templates, two-dimensional/two-dimensional (2D/2D) BiOI/BN nanocompounds were fabricated via an in situ growth method. Owing to the electrostatic interaction, the positively charged BiOI {001} facets prefer to contact the negatively charged BN {001} facet, thus inducing the exposure of BiOI {110} facets. This was identified via X-ray diffraction and transmission electron microscopy analyses. Compared with BiOI {001} facets, there were more lattice oxygen atoms in the BiOI {110} facets. Thus, the exposure of BiOI {110} facets would promote more surface lattice oxygen atoms exposed on the surface of BiOI, which was confirmed by X-ray photoelectron spectroscopy and density functional theory calculations. To evaluate the photocatalytic oxidation performance of BiOI/BN, the photocatalytic NO oxidation reaction was tested under visible light irradiation (λ > 420 nm). Among all the nanocompounds, the BiOI/BN-1.0:1.4 nanocompound exhibited the best NO oxidation ratio of 44.2%, which was almost 30 times higher than that of pristine BiOI (1.4%). The enhanced photocatalytic activity could be attributed to the following two aspects. One, the successful combination of BN effectively promoted the separation of photogenerated carriers, which was identified by steady-state and time-resolved fluorescence spectra, transient photocurrent responses, and electrochemical impedance spectra. Two, benefiting from the introduction of BN nanosheets, BiOI tends to mainly expose the oxygen-rich {110} facets. As a result, the content of O on the BiOI surface increased from 38.3% to 46.6%. Thus, NO preferred to adsorb on the {110} facets of BiOI nanosheets, which was confirmed by theoretical and experimental results. More importantly, the adsorbed NO spontaneously combined with the lattice oxygen atom of the BiOI (110) surface to form nitrogen dioxide (NO2). These findings can provide a novel strategy to tune exposed oxygen-rich facets by constructing 2D/2D photocatalysts for ensuring efficient photocatalytic oxidation performance.

MSC2000:

• O643