Wenqi Wang, Xiajie Zhang, Ting Gao, Lin Ju*, Dongqiu Zhao*, Enzhou Liu*

Cite this article: Chin. J. Struct. Chem., 2026, 45(8), 100961. DOI: 10.1016/j.cjsc.2026.100961

Publication date: August 1, 2026

Keywords: Photoelectrocatalyst; H₂S conversion; Cd_0.5Zn_0.5S; TiO₂ nanotube; S-scheme heterojunction

ABSTRACT

The development of mild, environmentally-friendly, and low-energy hydrogen sulfide (H2S) conversion technologies is critical for energy and environmental sustainability. Herein, a cadmium zinc sulfide/titanium dioxide (Cd0.5Zn0.5S/TiO2) heterojunction photoanode was fabricated via hydrothermal deposition of Cd0.5Zn0.5S nanoparticles on TiO2 nanotube arrays, Subsequently, it was integrated with an iodide ion/triiodide ion (I-/I3-) redox-mediated system to construct a photoelectrocatalytic (PEC) platform for resource utilization of H2S. At an applied bias of 1.8 V, the Cd0.5Zn0.5S/TiO2 heterojunction achieved a photocurrent density of 1.9 mA·cm-2, which was 5.7 times that of pure TiO2. Moreover, it maintained a stable photocurrent density of 0.98 mA·cm-2 at 0.6 V. Mechanistic analyses indicated that the staggered band structure of the heterojunction enhanced photogenerated carrier separation, while the I-/I3- cycle enabled selective oxidation of H2S to elemental sulfur (S0), thereby preventing the formation of polysulfides and the passivation of the photoanode. A single 5 h PEC cycle yielded 25 mL of H2 and recoverable sulfur, realizing synchronous hydrogen (H2) production and H2S detoxification without the need for complex separation steps. This research offers a novel material design strategy for high-performance PEC-H2S conversion systems and provides technical insights for green valorization of sulfide pollutants.