Spatial Heterojunction in Nanostructured TiO 2 and Its Cascade Effect for Efficient Photocatalysis

作者：Yi Lu, Xiaolong Liu, He Li, Yuexing Zhang, Zhi-Yi Hu, Ge Tian, Xiu Cheng, Si-Ming Wu, Yuan-Zhou Li, Xiao-Hang Yang, Xiao-Hang Yang, Liying Wang, Jia-Wen Liu, Christoph Janiak, Ganggang Chang, Weihua Li, Gustaaf Van Tendeloo, Xiao-Yu Yang, Xiao-Yu Yang, Bao‐Lian Su · 发表于：Nano Letters · 年份：2020 · DOI：10.1021/acs.nanolett.9b05121 · 被引用次数：108 · 研究领域：Advanced Photocatalysis Techniques、Quantum Dots Synthesis And Properties、Carbon and Quantum Dots Applications

A highly efficient photoenergy conversion is strongly dependent on the cumulative cascade efficiency of the photogenerated carriers. Spatial heterojunctions are critical to directed charge transfer and, thus, attractive but still a challenge. Here, a spatially ternary titanium-defected TiO 2 @carbon quantum dots@reduced graphene oxide (denoted as V Ti @CQDs@rGO) in one system is shown to demonstrate a cascade effect of charges and significant performances regarding the photocurrent, the apparent quantum yield, and photocatalysis such as H 2 production from water splitting and CO 2 reduction. A key aspect in the construction is the technologically irrational junction of Ti-vacancies and nanocarbons for the spatially inside-out heterojunction. The new “spatial heterojunctions” concept, characteristics, mechanism, and extension are proposed at an atomic-/nanoscale to clarify the generation of rational heterojunctions as well as the cascade electron transfer.