Approaching photocatalysts characterization under real conditions: In situ and operando studies

Abstract Operando and in situ studies of photocatalysts are capturing the growing interest of the scientific community as they constitute powerful tools for accessing real information about molecular-scale mechanisms. However, the need for simultaneous illumination imposes certain experimental constraints. Some spectroscopic techniques such as FTIR and XAS can be readily adapted for photocatalytic processes by means of dedicated reaction setups, mainly for mechanistic and kinetic studies. However, the use of other valuable analytical tools such as Raman, XPS, EPR, or NMR is still scarce due to the specific drawbacks of using these techniques under photocalytic conditions. This chapter provides a wide panorama of the latest progress in the use of these advanced characterization methodologies in photocatalysis, providing a perspective of the achievements so far reached and the limitations still faced by the different technologies.

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