0D/1D Cd_(0.5)Zn_(0.5)S/VO_(2)S型异质结的构建及其可见光催化析氢性能研究

Construction of 0D/1D Cd_(0.5)Zn_(0.5)S/VO_(2)S-Scheme Heterojunction for Visible Light Photocatalytic Hydrogen Generation via Water Splitting

采用共沉淀法制备了零维/一维(0D/1D)Cd_(0.5)Zn_(0.5)S/VO_(2)(CZS/VO)S型异质结光催化剂。采用X射线粉末衍射仪、X射线光电子能谱仪、扫描和透射电子显微镜等,表征了样品的物相结构、元素组成及微观形貌等,测试了材料的可见光催化析氢性能。研究结果表明CZS/VO复合材料具有优异的可见光催化析氢活性。其中,当VO的质量分数为10%时,CZS/VO催化剂的析氢速率最高可达7.2 mmol·h^(-1)·g^(-1),是单相CZS的4.2倍,并且在四次循环试验中表现出良好的循环稳定性。这主要归因于其独特的0D/1D形貌和S型异质结的协同作用显著加速了光生载流子的界面迁移和分离,同时使载流子具有更高的氧化还原能力。

A S-scheme heterojunction photocatalyst of 0D/1D Cd_(0.5)Zn_(0.5)S/VO_(2) was prepared using a co-precipitation method.X-ray powder diffractometer,X-ray photoelectron spectroscopy,scanning and transmission electron microscopy were used to characterize the photocatalysts in terms of physical structure,elemental composition and microscopic morphology.Photocatalytic hydrogen generation properties of the photocatalysts were studied under visible light irradiation,and the results showed that the optimized CZS/VO composites possessed excellent visible photocatalytic hydrogen generation activity.Especially,when the mass fraction of VO was 10%,the hydrogen generation rate of the CZS/VO photocatalyst was up to 7.2 mmol·h^(-1)·g^(-1),which was 4.2 times higher than that of pristine CZS.Meanwhile,the photocatalyst exhibited good cycling stability in four cycling tests.This is mainly attributed to the synergistic effect of its unique 0D/1D morphology and the S-type heterojunction,which greatly accelerates the interfacial migration and segregation of photo-excited carriers and results in higher redox capacities of photo-induced charges.