Constructing TiO2@Bi2O3 multi-heterojunction hollow structure for enhanced visible-light photocatalytic performance. (15th November 2022)

• Record Type: Journal Article
• Authors: Yin, Zhengliang; Zhang, Xuanxuan; Yuan, Xinhua; Wei, Wenxian; Xiao, Yingguan; Cao, Shunsheng
• Is Part Of: Journal of cleaner production. Volume 375(2022)
• Publication Date: 2022-11-15
• Subjects: Multiple heterojunctions -- Hollow heterostructures -- Photocatalysis -- Organic pollutants; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2022.134112
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Combining heterojunction with advanced structures is a promising tool to enhance the photoelectrochemical performance of semiconductor photocatalysts for environmental remediation. Herein, a novel multi-heterojunction TiO2 @Bi2 O3 (MHTB) hollow photocatalyst is successfully constructed by loading Bi2 O3 nanoparticles on the surface of inner TiO2 and outside of TiO2 shell. Photoelectrochemical characterizations show that the formation of multiple heterojunctions at the TiO2 @Bi2 O3 interfaces facilitates faster separation and transfer of photoinduced charge carriers than that of conventionally reported p-n heterojunction photocatalysts. Because of the separated two layers of Bi2 O3 and unique hollow structure, the photocatalytic performance of MHTB is significantly improved, leading to excellent photo-degradation rate constant ( k = 0.0165 min −1 ) for the degradation of levofloxacin, which approaches 1.5-fold and 2.6-fold increase than that of TiO2 @Bi2 O3 @TiO2 (n-p-n heterojunction) and TiO2 @Bi2 O3 (n-p heterojunction), respectively. Notably, the MHTB photocatalyst exhibits an excellent anti-interference capability for the interference of environmental factors. Moreover, the photocatalytic activity, crystal structure, and bonding energy of MHTB photocatalyst remain unchanged after being used several times, indicating an excellent stability. Therefore, this finding opens a new door to develop highly active photocatalysts with multiple heterojunctions for efficient pollutant removal and environmental remediation. Graphical abstract: Image 1 Highlights: Multi-heterojunction TiO2 @Bi2 O3 photocatalyst (MHTB) was prepared for the first time. MHTB drove the efficient degradation (>98%) and mineralization (92.6%) of levofloxacin under visible light. Multi-heterojunction and hollow structure contributed to the degradation of levofloxacin. The degradation pathway and mechanism of levofloxacin was proposed.