• 文献标题:   Synthesis of Z-scheme cobalt porphyrin/nitrogen-doped graphene quantum dot heterojunctions for efficient molecule-based photocatalytic oxygen evolution
  • 文献类型:   Article
  • 作  者:   ZHONG Z, LIU JJ, XU X, CAO AH, TAO ZJ, YOU WF, KANG LT
  • 作者关键词:  
  • 出版物名称:   JOURNAL OF MATERIALS CHEMISTRY A
  • ISSN:   2050-7488 EI 2050-7496
  • 通讯作者地址:  
  • 被引频次:   10
  • DOI:   10.1039/d0ta10196f
  • 出版年:   2021

▎ 摘  要

Porphyrin-based photocatalytic oxygen evolution (POE) has exhibited great potential in artificial photosynthesis; however, a few reports exist on efficient nanocatalytic systems due to the fast photoinduced charge recombination. Here, cobalt(iii) tetraphenylporphyrin (CoP) nanowires (NWs) are first synthesized at a large-scale via a simple chemical reaction, and transformed in situ into zero-dimensional CoP/NGQDs nanocomposites by adding nitrogen-doped graphene quantum dots (NGQDs) as the template and dopant. Under the visible light irradiation, no detectable POE activity of CoP NWs is observed in an acid heterogeneous system, while the currently highest POE rate on the molecule (350 mu mol g(-1) h(-1)) is achieved with CoP/NGQDs as the photocatalyst. Systematic experiments reveal that the NGQDs-limiting self-assembly of CoP molecules along the axial direction and subsequent formation of Z-scheme CoP/NGQDs heterojunctions are crucial for efficient POE. The nanostructures lead to enough exposure of the central Co atom as POE active sites and longer recombination lifetime of the photoinduced charge in CoP/NGQDs (87.8 ps) than that in CoP NWs (32.2 ps) due to the generation of (CoP+center dot NGQDs(-))* exciplex. This work provides a new strategy to use a nature-like semiconductor molecule as a direct catalyst for artificial photosynthesis.