Rational design of CdS/BiOCl S-scheme heterojunction for effective boosting piezocatalytic H2 evolution and pollutants degradation performances

Pingyu Hao; Yali Cao; Xueer Ning; Ruqi Chen; Jing Xie; Jindou Hu; Zhenjiang Lu; Aize Hao

doi:10.1016/j.jcis.2023.02.075

Rational design of CdS/BiOCl S-scheme heterojunction for effective boosting piezocatalytic H₂ evolution and pollutants degradation performances

J Colloid Interface Sci. 2023 Jun:639:343-354. doi: 10.1016/j.jcis.2023.02.075. Epub 2023 Feb 16.

Authors

Pingyu Hao¹, Yali Cao¹, Xueer Ning¹, Ruqi Chen², Jing Xie¹, Jindou Hu¹, Zhenjiang Lu¹, Aize Hao³

Affiliations

¹ State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi, Xinjiang, PR China.
² Department of Industrial and Manufacturing Systems Engineering, Kansas State University, Manhattan, KS, United States.
³ State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources, College of Chemistry, Xinjiang University, Urumqi, Xinjiang, PR China. Electronic address: h1061717965@163.com.

PMID: 36812851
DOI: 10.1016/j.jcis.2023.02.075

Abstract

Piezocatalysis as an emerging technology is broadly applied in hydrogen evolution and organic pollutants degradation aspects. However, the dissatisfactory piezocatalytic activity is a severe bottleneck for its practical applications. In this work, CdS/BiOCl S-scheme heterojunction piezocatalysts were constructed and explored the performances of piezocatalytic hydrogen (H₂) evolution and organic pollutants degradation (methylene orange, rhodamine B and tetracycline hydrochloride) under strain by ultrasonic vibration. Interestingly, CdS/BiOCl presents a volcano-type relationship between catalytic activity and CdS contents, namely firstly increases and then decreases with the increase of CdS content. Optimal 20 % CdS/BiOCl endows superior piezocatalytic H₂ generation rate of 1048.2 μmol g^-¹h^-1 in methanol solution, which is 2.3 and 3.4 times higher than that of pure BiOCl and CdS, respectively. This value is also much higher than the recently reported Bi-based and most of other typical piezocatalysts. Meanwhile, 5 % CdS/BiOCl delivers the highest reaction kinetics rate constant and degradation rate toward various pollutants compared with other catalysts, which also exceeds that of the previously numerous results. Improved catalytic capacity of CdS/BiOCl is mainly ascribed to the construction of S-scheme heterojunction for enhancing the redox capacity as well as inducing more effective charge carriers separation and transfer. Moreover, S-scheme charge transfer mechanism is demonstrated via electron paramagnetic resonance and Quasi-In-situ X-ray photoelectron spectroscopy measurements. Eventually, a novel piezocatalytic mechanism of CdS/BiOCl S-scheme heterojunction has been proposed. This research develops a novel pathway for designing highly efficient piezocatalysts and provides a deeper understanding in construction of Bi-based S-scheme heterojunction catalysts for energy conservation and wastewater disposal applications.

Keywords: CdS/BiOCl S-scheme heterojunction; Charge carriers transfer; Piezocatalytic degradation of pollutants; Piezocatalytic mechanism; piezocatalytic H(2) evolution.