Multi-stepwise charge transfer via MOF@MOF/TiO₂ dual-heterojunction photocatalysts towards hydrogen evolution
2022
Chen, Yao | Yang, Dong | Xin, Xin | Yang, Zhongshan | Gao, Yuchen | Shi, Yonghui | Zhao, Zhanfeng | An, Ke | Wang, Wenjing | Tan, Jiangdan | Jiang, Zhongyi
Rational manipulation of the photogenerated charge transfer inside the photocatalyst is key to enhancing the photocatalytic performance. Herein, inspired by the charge transport chain in natural photosynthesis, a novel multi-stepwise charge transfer strategy is proposed for the ingenious design of photocatalysts. To confirm the effectiveness of this strategy, a kind of MOF@MOF/TiO₂ dual-heterojunction was constructed by depositing TiO₂ nanoparticles on the surface of core–shell MOF@MOF hetero-frameworks. The energy band potentials of the three moieties in MOF@MOF/TiO₂ exhibit a multi-stepwise characteristic, wherein the slight gradient difference of energy bands helps in deconcentrating the charge in multiple energy bands and affords a smaller interface resistance, thus rendering a high charge transfer efficiency. Accordingly, compared with the single-heterojunction counterparts with one-step charge transfer including MOF@MOF and MOF/TiO₂, the MOF@MOF/TiO₂ dual-heterojunction achieves a much higher photocatalytic hydrogen evolution rate of 7.108 mmol g⁻¹ h⁻¹ under full-spectrum irradiation. This study may offer a deep insight into the charge transfer behavior in the photocatalytic process, along with the rational design of high-performance photocatalysts for sustainable energy conversion applications.
显示更多 [+] 显示较少 [-]