@article{Liu2025, 
author = {Yuan Liu and Xiaojing Chu and Chen Zhu and Weidong Li and Chuanqi Li and Siyu Lu},
title = {Carbon quantum dots as photogenerated carrier transfer bridges in all-solid Z-scheme ZnIn2S4/CQDs/CeO2 heterostructures for efficient visible-light-driven photocatalytic hydrogen generation},
year = {2025},
journal = {Nano Research},
volume = {18},
number = {8},
pages = {94907559},
keywords = {carbon quantum dots, photocatalytic H2 generation, all-solid Z-scheme heterostructure, ZnIn2S4/CQDs/CeO2},
url = {https://www.sciopen.com/article/10.26599/NR.2025.94907559},
doi = {10.26599/NR.2025.94907559},
abstract = {The development of efficient and stable visible-light-driven hydrogen (H2) generation photocatalysts plays a crucial role in sustainable energy conversion. In this study, we constructed an all-solid Z-scheme heterostructure by integrating carbon quantum dots (CQDs) as a photogenerated carrier transfer bridge between ZnIn2S4 and CeO2. The unique structure of ZnIn2S4/CQDs/CeO2 facilitates the efficient separation and transfer of photogenerated electron-hole pairs, while the CQDs act as a solid-state electron mediator, enhancing interfacial charge transfer and suppressing recombination. Under visible-light irradiation (λ ≥ 420 nm), when the concentration of ZnIn2S4 is 40%, the hydrogen generation rate of ZnIn2S4/CQDs/CeO2-2 reaches 7.7 mmol·g−1·h−1, which is 12.8 times higher than that of unmodified ZnIn2S4 (0.6 mmol·g−1·h−1) and significantly greater than that of ZnIn2S4/CeO2 (4.2 mmol·g−1·h−1). Furthermore, the all-solid Z-scheme configuration ensures excellent stability, as demonstrated by prolonged cycling tests. We investigated CQDs as a bridge to facilitate the vector transfer of photogenerated electrons from ZnIn2S4 to CeO2 through density functional theory calculations. Additionally, X-ray photoelectron spectroscopy results confirmed the Z-scheme mechanism of photogenerated carrier transfer within the ZnIn2S4/CQDs/CeO2 heterojunction. This study not only demonstrates an effective approach for promoting charge transfer in nanocomposites using CQDs but also provides a new strategy for developing efficient hydrogen evolution photocatalysts without the involvement of precious metals.}
}