Identifying the Role of Pt Active Species in CO‐Sensitive Photocatalytic H <sub>2</sub> Evolution
Abstract
Abstract Platinum (Pt) has been widely employed in photocatalytic H 2 production. However, the influence of CO on proton reduction to H 2 over Pt active species remains unknown. Herein, using Pt/Nb 2 O 5 as a model catalyst, the role of Pt active species in CO‐sensitive photocatalytic H 2 evolution is evaluated. Our results reveal that Pt 4+ species exhibits superior activity in H 2 production when the CO‐to‐Pt molar ratio is low ( n CO / n Pt ≤ 1.3), but their photocatalytic performance is suppressed at a high n CO / n Pt ratio (>1000). By contrast, increasing the loading amount of Pt suppresses Pt 4+ species formation and the low valence state Pt species show inferior activity for H 2 production, which is almost unaffected by the n CO / n Pt ratio. The CO‐TPD results, in situ FTIR spectra, and DFT calculations indicate that the role of adsorbed CO molecules is to impede the interaction between H 2 O and Pt 4+ species and prevent the generation of *H species for H 2 production. Significantly improving the H 2 production rate by purging with argon suggests the importance of inhibiting the adsorption of CO on Pt 4+ species. This study sheds light on the generation and transformation of active H species in CO‐participated photocatalytic systems, which is missing in previous works, and is more significant for rationally designing Pt‐based photocatalysts in large‐scale H 2 production.
Article Details
Authors (11)
Kaiyi Su
Key Laboratory of Supramolecular Photochemistry & CAS‐HKU Joint Laboratory on New Materials New Cornerstone Science Laboratory Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing P.R. China
Tengshijie Gao
Key Laboratory of Supramolecular Photochemistry & CAS‐HKU Joint Laboratory on New Materials New Cornerstone Science Laboratory Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing P.R. China
Haixia Liu
Shuai Zhou
Department of Global Development, Cornell University
Chen Zhang
Shenzhen Institute for Quantum Science and Engineering, Department of Chemistry, and Department of Physics
Ke Zhang
Can Li
State Key Laboratory of Catalysis
Jintao Ru
Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS‐HKU Joint Laboratory on New Materials, New Cornerstone Science Laboratory, Technical Institute of Physics and Chemistry & University of Chinese Academy of Sciences Chinese Academy of Sciences Beijing 100190 P.R. China
Wangsheng Chu
National Synchrotron Radiation Laboratory
Chen‐Ho Tung
School of Chemistry and Chemical Engineering Shandong University Jinan China
Li‐Zhu Wu
Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences Beijing China