Spatial separation of photo-induced charge carriers in a Na3VO2B6O11 polar material and its enhanced photocatalytic activity

• Published in: Applied surface science Vol. 556; p. 149809
• Main Authors: Chen, Jiayu, Zhai, Yufei, Yu, Yang, Luo, Jianmin, Fan, Xiaoyun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2021
• Subjects: Built-in electric field; Photo-activity; Polar materials; Spatial separation; Polar materials; Built-in electric field; Spatial separation; Photo-activity
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2021.149809

The effective spatial separation and migration of photo-induced electron-hole pairs to surface active sites is governed by the built in electric field of a polar Na3VO2B6O11 (NVB) material. [Display omitted] •Au and PbO2 were deposited onto different face of a polar Na3VO2B6O11(NVB) material.•The photo-induced e- and h+ transferred to (020) and (200) plane of the NVB crystal.•Au-NVB showed excellent catalytic activity for the degradation of pollutants. The effective spatial separation and migration of photo-induced electron-hole pairs to surface active sites is a challenging topic in the field of photocatalysis. Rational design and precise control over charge carriers’ transportation in polar materials with built-in electric field are favorable for achieving its optimal photocatalytic performance. By deposition of Au nanoparticles (Au NPs) and high valence metal oxides PbO2 onto different face of borate-based polar Na3VO2B6O11 (NVB) material, the transfer behavior of the photo charges was systemically studied. It was found that under light irradiation, the electrons were transferred to (020) plane and the holes were aggregated on (200) plane of the crystal, respectively. The Au-NVB samples shown the best photocatalytic activity, finishing the reaction in just 20 min and 100 min for the degradation of 2-chlorophenol and tetracycline pollutants, respectively, which is 1.2 times that of pure NVB. This discovery complements the understanding of spatial separation of photo-induced charges in borate based polar materials and provides great potential for further application of such materials.