Exploring different photocatalytic behaviors of CdxZn1−xSeyS1−y gradient-alloyed quantum dots via composition regulation
| Autor: | Runda Huang, Yuxin Liu, Chuanglei Wang, Xiao Liu, Xiangjing Ying, Menglong Zhang, Huaimin Gu, Dongxiang Luo, Zheng Liu, Weizhe Wang |
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| Rok vydání: | 2021 |
| Předmět: |
Materials science
02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Catalysis 0104 chemical sciences Band bending Reaction rate constant Chemical physics Quantum dot Photocatalysis Energy transformation Charge carrier Reactivity (chemistry) 0210 nano-technology Electronic band structure |
| Zdroj: | Catalysis Science & Technology. 11:5917-5930 |
| ISSN: | 2044-4761 2044-4753 |
| DOI: | 10.1039/d1cy01142a |
| Popis: | Gradient-alloyed quantum dots (QDs) are new and interesting photocatalysts for efficient solar-to-chemical energy conversion to solve increasing energy and environmental problems. Nevertheless, few studies have been devoted to exploring structure–property relationships of gradient-alloyed QDs via the composition regulation. Herein we offer band-engineered gradient-alloyed QDs CdxZn1−xSeyS1−y prepared by stoichiometry control over the composition manipulation and has a funnel-shaped energy level. The effect of band structure on the photocatalytic performance of CdxZn1−xSeyS1−y QDs demonstrated that the regulation of light-harvesting range, charge carrier separation ability and redox reactivity can be achieved by composition and size adjustments. The results show that red QDs have the best electron/hole separation ability and widest photon capturing scope, while blue QDs possess the highest redox reactivity, realizing the contaminant degradation and CO2 reduction, simultaneously, with a high apparent rate constant kapp of 0.4237 min−1. Moreover, green QDs could be employed as a well-luminescent material owing to the fast electron–hole recombination rate. The mechanistic investigations reveal that different activities are dependent on a combination of two factors, that are ion migration-induced conversion of electron configuration and size-induced band bending. The understanding obtained in the present study is valuable for on-demand designing the unique properties of gradient-alloyed QDs. |
| Databáze: | OpenAIRE |
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