Facile synthesis of Bi2O3 nanocrystals for photocatalytic NO oxidation and its conversion pathway via in situ DRIFTS. (December 2020)

• Record Type: Journal Article
• Authors: He, Tiantian; Cao, Tong; Huo, Wangchen; Guo, Ziyang; Wang, Ziyao; Liu, Xiaoying; Zhang, Yuxin; Ye, Gui; Zhang, Shilian
• Is Part Of: Materials research bulletin. Volume 132(2020)
• Publication Date: 2020-12
• Subjects: β-Bi2O3 -- Crystal structure -- Visible light photocatalysis -- Reaction process -- In situ DRIFTS; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2020.111007
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Facile synthesis two polymorphs of Bi2 O3 nanoparticle. Comparing carrier separation efficiency, band gap and photocatalytic activity between β-Bi2 O3 and α-Bi2 O3 . ESR spectra indicated that the superoxide radical ( O2 − ) was the main active radicals. In situ DRIFTS spectra is used to investigate the NO oxidation process and mechanism. Abstract: In this work, the two different polymorphs of Bi2 O3, including α-Bi2 O3 and β-Bi2 O3, were fabricated by the post-calcined the precursor at 300 and 500 °C respectively. The pathway of photocatalytic NO oxidation over the as-prepared photocatalyst (β-Bi2 O3 ) was explored. The results showed that NO removal ratio on as-synthesis samples followed the order: β-Bi2 O3 (32 %) > the precursor (13 %) > α-Bi2 O3 (5 %). The ESR and in situ DRIFTS demonstrated that the superoxide ( O2 − ), as the main radical, can react with the absorbed NO on the surface of β-Bi2 O3 to generate the final products NO3 − and NO2 − . Therefore, such findings reveal the possible photocatalytic pathway of NO oxidation on β-Bi2 O3 based on in situ DRIFTS and give insight into understanding the polymorphism of Bi2 O3 in efficient photocatalytic NO oxidation under the visible light.