Rationally Designed CdS-Based Ternary Heterojunctions: A Case of 1T-MoS2 in CdS/TiO2 Photocatalyst

Wenqian Chen; Shaomei Zhang; Ganyu Wang; Gang Huang; Zhichong Yu; Yirui Li; Liang Tang

doi:10.3390/nano11010038

Rationally Designed CdS-Based Ternary Heterojunctions: A Case of 1T-MoS₂ in CdS/TiO₂ Photocatalyst

Nanomaterials (Basel). 2020 Dec 25;11(1):38. doi: 10.3390/nano11010038.

Authors

Wenqian Chen^{1

2}, Shaomei Zhang^{1

3}, Ganyu Wang^{1

3}, Gang Huang⁴, Zhichong Yu^{1

3}, Yirui Li^{1

3}, Liang Tang^{1

3}

Affiliations

¹ Key Laboratory of Organic Compound Pollution Control Engineering, Ministry of Education, Shanghai 200444, China.
² Shanghai Institute of Applied Radiation, Shanghai University, 20 Chengzhong Road, Shanghai 201800, China.
³ School of Environmental and Chemical Engineering, Shanghai University, Shanghai 200444, China.
⁴ Physical Science and Engineering Division King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.

Abstract

As promising heterojunction photocatalysts, the binary CdS-based heterojunctions were investigated extensively. In most of the reported CdS-based heterojunctions, however, electrons come from the semiconductor with wide band gap (e.g., TiO₂) would limit the visible-light absorption of CdS and hence lower the performance. In this work, we introduced 1T-MoS₂ to form a novel ternary heterojunction, namely CdS/1T-MoS₂/TiO₂, in which 1T-MoS₂ has more positive conduction band than CdS and TiO₂. The hydrogen evolution rate of CdS/1T-MoS₂/TiO₂ reaches 3.15 mmol g^-1 h^-1, which is approximately 12 and 35 times higher than that of pure CdS and CdS/TiO₂ binary heterojunction under the same conditions, respectively. This performance enhancement could be attributed to the presence of 1T-MoS₂ and a plausible mechanism is proposed based on photoelectrochemical characterizations. Our results illustrate that the performance of CdS-based heterojunctions for solar hydrogen evolution can be greatly improved by appropriate materials selection.

Keywords: CdS/1T-MoS2/TiO2; heterojunction; hydrogen evolution; photocatalyst.

Abstract

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