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Abstract Photo‐electrochemistry is the major trajectory for directly transforming solar energy into chemical compounds. The performance of a photo‐electrochemical (PEC) system is directly related to the interfacial electrical band energy landscape. Recently, piezotronics has stood out as a promising strategy for tuning interfacial energetics. It applies intrinsic or deformation‐induced ionic displacements (ferroelectric and piezoelectric polarizations) to engineer the interfacial charge distribution, and thereby the band structures of PEC electrodes. Here, contemporary research efforts of coupling piezotronics with photo‐electrochemisty are reviewed. Quantitative band diagrams of a polarization‐tuned semiconductor–electrolyte junction are first introduced, with an emphasis on the impact of interface chemistry. Experimental advances of employing piezoelectric and ferroelectric polarizations to enhance the charge separation and transportation, and surface kinetics of PEC water splitting are discussed. Finally, critical challenges of applying piezotronics in PEC systems and promising solutions are presented.
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Piezotronic modulations in electro- and photochemical catalysis
Electrochemical catalyst design and optimization primarily relies on understanding and facilitating interfacial charge transfer. Recently, piezotronics have emerged as a promising method for tuning the interfacial energetics. The unique band-engineering capability using piezoelectric or ferroelectric polarization could lead to performance gains for electrochemical catalysis beyond what can be achieved by chemical or structural optimization. This article addresses the fundamentals of surface polarization and corresponding band modulation at solid–liquid interfaces. The most recent advances in piezotronic modulations are discussed from multiple perspectives of catalysis, including photocatalytic, photoelectrochemical, and electrochemical processes, particularly for energy-related applications. The concept of piezocatalysis, a direct conversion of mechanical energy to chemical energy, is introduced with an example of mechanically driven water splitting. While still in the early stages, piezotronics is envisioned to become a powerful tool for revolutionizing electrochemical catalysis.
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- Award ID(s):
- 1709025
- PAR ID:
- 10098791
- Date Published:
- Journal Name:
- MRS Bulletin
- Volume:
- 43
- Issue:
- 12
- ISSN:
- 0883-7694
- Page Range / eLocation ID:
- 946 to 951
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1557/mrs.2018.264
