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Title: Dual Protection Layer Strategy to Increase Photoelectrode–Catalyst Interfacial Stability: A Case Study on Black Silicon Photoelectrodes
Abstract

Photoelectrode degradation under harsh solution conditions continues to be a major hurdle for long‐term operation and large‐scale implementation of solar fuel conversion. In this study, a dual‐layer TiO2protection strategy is presented to improve the interfacial durability between nanoporous black silicon and photocatalysts. Nanoporous silicon photocathodes decorated with catalysts are passivated twice, providing an intermediate TiO2layer between the substrate and catalyst and an additional TiO2layer on top of the catalysts. Atomic layer deposition of TiO2ensures uniform coverage of both the nanoporous silicon substrate and the catalysts. After 24 h of electrolysis at pH = 0.3, unprotected photocathodes layered with platinum and molybdenum sulfide retain only 30% and 20% of their photocurrent, respectively. At the same pH, photocathodes layered with TiO2experience an increase in photocurrent retention: 85% for platinum‐coated photocathodes and 91% for molybdenum sulfide–coated photocathodes. Under alkaline conditions, unprotected photocathodes experience a 95% loss in photocurrent within the first 4 h of electrolysis. In contrast, TiO2‐protected photocathodes maintain 70% of their photocurrent during 12 h of electrolysis. This approach is quite general and may be employed as a protection strategy for a variety of photoabsorber–catalyst interfaces under both acidic and basic electrolyte conditions.

 
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NSF-PAR ID:
10461689
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Materials Interfaces
Volume:
6
Issue:
8
ISSN:
2196-7350
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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