Enhanced photocatalytic activity of La1-xSrxCoO3/Ag3PO4 induced by the synergistic effect of doping and heterojunction. Issue 14 (15th July 2021)

• Record Type: Journal Article
• Authors: Chen, Jieming; Chen, Xiaojuan; Li, Ning; Liang, Yunqing; Yu, Chunmu; Yao, Liang; Lai, Yiqi; Huang, Yaole; Chen, Hefeng; Chen, Yuxiang; Fan, Zijian
• Is Part Of: Ceramics international. Volume 47:Issue 14(2021)
• Page Start: 19923
• Page End: 19933
• Publication Date: 2021-07-15
• Subjects: Ag3PO4 -- Doping -- Heterojunction -- Oxygen vacancies -- Visible light catalysis; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2021.04.006
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: This study sought to design and synthesize a series of perovskite-based La1-x Srx CoO3 /Ag3 PO4 (with x = 0–1) heterojunction photocatalysts with different Strontium (Sr) doping contents by a simple sol-gel method and properties of the material were comprehensively characterized. Moreover, tetracycline (TC) was chosen as the target pollutant to assess the effect of Sr doping on the catalytic performance of LaCoO3 /Ag3 PO4 . Our results demonstrated that the partial replacement of La 3+ with Sr 2+ coupled with shifting Co 3+ to the mixed-valence state of Co 3+ -Co 4+ led to the formation of substantially more oxygen vacancies in the crystal lattice of La1-x Srx CoO3 /Ag3 PO4 . Therefore, the doped catalyst La1-x Srx CoO3 /Ag3 PO4 exhibited enhanced photocatalytic performance. When x = 0.9, the obtained La0·1 Sr0·9 CoO3 /Ag3 PO4 exhibit an optimal performance for TC degradation. Kinetic analyses demonstrated that the degradation rate constant of TC in La0·1 Sr0·9 CoO3 /Ag3 PO4 system was 0.0098 min −1, which is 1.78 times that of LaCoO3 /Ag3 PO4, and 2.45 times that of SrCoO3 /Ag3 PO4 . Additionally, free radical sequestration experiments indicated that OH, h +, and O2 − all participated in the degradation of TC in the following order: h + >O2 − >OH . Finally, analyses of photocatalytic mechanisms suggested that the enhanced photocatalytic activity of La0·1 Sr0·9 CoO3 /Ag3 PO4 was due to its strong electron transfer properties and the formation of substantially more surface oxygen vacancies in Sr-doped La0·1 Sr0·9 CoO3 .