Photoelectrolysis of TiO2 is highly localized and the selectivity is affected by the light

Christian Iffelsberger, Siowwoon Ng, Martin Pumera

Research output: Contribution to journalArticlepeer-review

Abstract

On the way to sustainable prosperity for future generations, photoelectrochemistry is becoming a key area for energy conversion and the environmentally friendly generation of chemical resources because it combines the advantages of electrochemical and photochemical processes. Highly active catalyst materials with excellent selectivity towards the desired reaction are certainly required for efficient processes. Understanding the underlying processes, including detailed in situ information, facilitates the design and development of catalyst materials. In this work, we utilize the scanning photoelectrochemical microscopy for the spatially resolved in situ investigation of the electrochemical and photoelectrochemical evolution of hydrogen, oxygen, reactive oxygen species, and chlorine for energy conversion. Herein, we demonstrate that the activity and the selectivity of the TiO2 photoelectrocatalyst are highly localized despite their apparently uniform composition based on regular morphological characterization. Furthermore, the results suggest that the illumination dramatically changes the selectivity in electrolysis reactions, which is demonstrated on the competing oxygen- and chlorine- evolution reaction. Consequently, this leads to the critical implication that the activity and selectivity should not be considered uniform per se, especially under the illumination. This implies that light might be used for controlling the selectivity in electrolysis reactions. Such discovery shall dramatically impact the optimization of photoelectrocatalysts in general.

Original languageEnglish
Article number136995
JournalChemical Engineering Journal
Volume446
DOIs
Publication statusPublished - 2022 Oct 15

Bibliographical note

Funding Information:
M.P. acknowledges the financial support by the Grant Agency of the Czech Republic (GACR EXPRO: 19-26896X). C.I. acknowledges the financial support by the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 888797. C.I. and S.N. gratefully acknowledge the CzechNanoLab project LM2018110 funded by MEYS CR for the financial support of the measurements and sample fabrication at CEITEC Nano Research Infrastructure. The authors thank Dr. F. Novotný from BUT for designing and 3D printing the housing and Dr. K. Ghosh from BUT for help with XRD measurements and analysis.

Funding Information:
M.P. acknowledges the financial support by the Grant Agency of the Czech Republic (GACR EXPRO: 19-26896X). C.I. acknowledges the financial support by the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie grant agreement No. 888797. C.I. and S.N. gratefully acknowledge the CzechNanoLab project LM2018110 funded by MEYS CR for the financial support of the measurements and sample fabrication at CEITEC Nano Research Infrastructure.

Publisher Copyright:
© 2022 Elsevier B.V.

All Science Journal Classification (ASJC) codes

  • Chemistry(all)
  • Environmental Chemistry
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

Fingerprint

Dive into the research topics of 'Photoelectrolysis of TiO2 is highly localized and the selectivity is affected by the light'. Together they form a unique fingerprint.

Cite this