2D/2D heterojunctions of WO3 nanosheet/K+Ca2Nb3O10− ultrathin nanosheet with improved charge separation efficiency for significantly boosting photocatalysis. Issue 16 (11th July 2017)

• Record Type: Journal Article
• Authors: Ma, Xiaodong; Jiang, Deli; Xiao, Peng; Jin, Yu; Meng, Suci; Chen, Min
• Is Part Of: Catalysis science & technology. Volume 7:Issue 16(2017)
• Page Start: 3481
• Page End: 3491
• Publication Date: 2017-07-11
• Subjects: Catalysis -- Periodicals; 541.395
• DOI: 10.1039/c7cy00976c
• Languages: English
• ISSNs: 2044-4753

Abstract

Abstract : Harvesting solar energy using semiconductor photocatalysts for wastewater decontamination offers a greener solution to address serious environmental crises. Abstract : Harvesting solar energy using semiconductor photocatalysts for wastewater decontamination offers a greener solution to address serious environmental crises. Delamination of layer photocatalysts into ultrathin two-dimensional (2D) nanosheets has induced fascinating properties such as electronic/protonic-conductivity and photocatalytic and fluorescent properties. K + Ca2 Nb3 O10 − is one prominent type of such materials, which is derived from the Dion–Jacobsen phase KCa2 Nb3 O10 by exfoliation. Here, a Z -scheme WO3 /K + Ca2 Nb3 O10 − binary 2D–2D heterojunction photocatalyst is successfully constructed through an easy hydrothermal coassembly method at room temperature. The as-synthesized WO3 /K + Ca2 Nb3 O10 − photocatalyst exhibited remarkable improvement in the photodegradation performance of tetracycline hydrochloride under simulated sunlight irradiation as compared to pristine WO3 and K + Ca2 Nb3 O10 − nanosheets. Sample 20%-WO3 /K + Ca2 Nb3 O10 − exhibited optimum efficiency, which is about 5.1-fold and 2-fold higher than those of WO3 and K + Ca2 Nb3 O10 −, respectively. Such an improvement is mainly related to its strongly coupled heterointerfaces, enlarged specific surface area and improved charge carrier separation and transfer. Radical capturing experiments and the spin-trapping ESR technique demonstrate that both ˙O2 − and h + are the important active species responsible for the tetracycline hydrochloride degradation process over the nanosheet heterojunctions.