Maoqing Yu,Xiaojing Zhao,Xiangge Wang,Lichun Chen,Xiangyu Chen,Miaoling Huang,Wen-Jie Chen,Xiaoyang Pan
Piezocatalytic hydrogen evolution represents a promising strategy for generating sustainable energy. The construction of heterojunctions can realize the efficient separation and migration of charges and thus achieve enhanced H2 evolution performance. In this study, we report the fabrication of a CdS-Cd2Nb2O7 (CdS-CNO) heterojunction piezocatalyst with cadmium vacancies aimed at improving hydrogen evolution performance. Cadmium sulfide (CdS) was combined with cadmium niobate (Cd2Nb2O7, CNO) to form a heterojunction through a photodeposition strategy. By regulating the photodeposition time, CdS-CNO nanocomposites with varying CdS contents were successfully obtained. Cadmium vacancies were introduced into the CNO matrix during the photodeposition process, where cadmium ions within the CNO lattice reacted with sulfur ions to form CdS, resulting in the creation of cadmium vacancies. Experimental results demonstrated that the CdS-CNO-4 composite, with an optimized CdS content, exhibited the highest piezoelectric hydrogen production activity of 6.01 mmol·g–1·h–1, which is much higher than those of most previously reported piezocatalysts. The enhanced performance is attributed to the strong internal electric field generated by piezoelectric polarization and efficient charge carrier separation facilitated by the heterojunction and cadmium vacancies. This study aims to provide a strategy for developing highly efficient heterojunction piezocatalysts.
The photocatalytic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) is a promising process with significant implications for sustainable energy and environmental applications. However, achieving highly selective DFF production from HMF remains a challenging task, particularly due to the dependency of molecular O 2 activation on the composition and exposed facets of nanomaterials. This study investigates the impact of different preferential facets of hydrothermally synthesized cadmium sulfide (CdS) morphologies—including hollow spheres, nanorods, and flower-like structures—on the photocatalytic oxidation of HMF to DFF. The findings reveal that the preferential CdS (002) facet and Cd vacancies in the hollow sphere morphology significantly enhance photocatalytic activity, achieving 68% HMF conversion and 89% selectivity for DFF production within 12 h of reaction time. This work highlights the critical role of material composition and facet orientation in optimizing photocatalytic processes for selective oxidation reactions, offering a potential strategy for the design of advanced photocatalysts in sustainable chemical production.