2D Z-scheme TiO2/SnS2 heterojunctions with enhanced visible-light photocatalytic performance for refractory contaminants and mechanistic insights. (16th August 2021)

• Record Type: Journal Article
• Authors: Gao, Juan; Sun, Xiaowei; Zheng, Lingcheng; He, Gang; Wang, Yanfen; Li, Yang; Liu, Yin; Deng, Jiale; Liu, Mei; Hu, Jintao
• Is Part Of: New journal of chemistry. Volume 45:Number 35(2021)
• Page Start: 16131
• Page End: 16142
• Publication Date: 2021-08-16
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/d1nj02247d
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : The Z-scheme TiO2 /SnS2 nanosheet heterojunctions significantly broaden the visible photoabsorption region and accelerate the separation of e–h pairs, thereby resulting in a higher photocatalytic activity for refractory contaminants. Abstract : In this work, a two-dimensional (2D) TiO2 /SnS2 nanosheet heterojunction with a novel face-to-face structure was fabricated by a two-step hydrothermal method. The morphology, microstructure, chemical components, as well as optical features, photocatalytic activity, photoelectrochemical (PEC) performance and catalytic mechanism of TiO2 /SnS2 were systematically investigated. The results indicate that the 2D TiO2 /SnS2 sheet-like heterojunction can enhance the photocatalytic activity for refractory contaminants including methyl orange (MO), methylene blue (MB), rhodamine B (RhB), and tetracycline antibiotics (TCs). TiO2 /SnS2 with a mole ratio of Sn : Ti = 0.15 : 1 possesses the best photocatalytic activity and PEC performance. The corresponding photocurrent density (∼3.79 μA cm −2 ) is 3.4 and 2.6 times higher than those of TiO2 (∼1.11 μA cm −2 ) and SnS2 (∼1.45 μA cm −2 ). Enhanced photocatalytic activity and PEC performance are ascribed to the synergistic effect of TiO2 /SnS2 heterostructures, including (i) Z-scheme band alignments, which can effectively inhibit photogenerated carrier recombination, (ii) modulation of narrow band SnS2, which can broaden the visible photoabsorption region, and (iii) face-to-face structures, which can provide a convenient transport channel for photoinduced carriers.