Presentation Information
[2C02]Operando surface-sensitive electron-yield soft X-ray absorption spectroscopy study on photocatalytic activation of Cu2O/Fe3O4 for hydrogen evolution from formic acid
*Kota Enomoto1, Fumitoshi Kumaki1, Ryo Toyoshima2, Kazuhiko Mase3,4, Hiroshi Kondoh1 (1. Keio University (Japan), 2. The University of Tokyo (Japan), 3. Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK) (Japan), 4. Graduate Institute for Advanced Studies, SOKENDAI (Japan))
Catalyst activation is often governed by surface chemical changes, but direct correlation between surface species and catalytic activity remains challenging. We developed an operando analysis system by a combination of surface-sensitive electron-yield soft X-ray absorption spectroscopy (EY-sXAS) and online mass spectrometry (MS) to study Cu2O/Fe3O4 photocatalysts for H2 production from formic acid. Under formic acid vapor and visible-light irradiation, the H2 evolution rate gradually increased with irradiation time. The temporal increase in Cu0 closely correlated with H2 evolution, demonstrating that photoinduced surface Cu0 formation is essential for the activation. Further measurements revealed that the coupling between Cu2O and Fe3O4 promotes charge separation, enabling electron transfer to Cu2O and hole transfer to Fe3O4. These results show that the operando EY-sXAS/MS observation directly links the surface valence change with the photocatalytic activity.
Password required to view
Comment
To browse or post comments, you must log in.Log in