Tailoring Interfaces for Enhanced Methanol Production from Photoelectrochemical CO2 Reduction
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- Yale University, New Haven, CT (United States); Yale University, West Haven, CT (United States); The Center for Hybrid Approaches in Solar Energy to Liquid Fuels (CHASE)
- Emory University, Atlanta, GA (United States)
- Yale University, New Haven, CT (United States); Yale University, West Haven, CT (United States)
- University of Pennsylvania, Philadelphia, PA (United States)
- Yale University, New Haven, CT (United States)
- Yale University, West Haven, CT (United States)
- University of North Carolina at Chapel Hill, NC (United States)
Efficient and stable photoelectrochemical reduction of CO2 into highly reduced liquid fuels remains a formidable challenge, which requires an innovative semiconductor/catalyst interface to tackle. In this study, we introduce a strategy involving the fabrication of a silicon micropillar array structure coated with a superhydrophobic fluorinated carbon layer for the photoelectrochemical conversion of CO2 into methanol. The pillars increase the electrode surface area, improve catalyst loading and adhesion without compromising light absorption, and help confine gaseous intermediates near the catalyst surface. The superhydrophobic coating passivates parasitic side reactions and further enhances local accumulation of reaction intermediates. Upon one-electron reduction of the molecular catalyst, the semiconductor–catalyst interface changes from adaptive to buried junctions, providing a sufficient thermodynamic driving force for CO2 reduction. These structures together create a unique microenvironment for effective reduction of CO2 to methanol, leading to a remarkable Faradaic efficiency reaching 20% together with a partial current density of 3.4 mA cm–2, surpassing the previous record based on planar silicon photoelectrodes by a notable factor of 17. Furthermore, this work demonstrates a new pathway for enhancing photoelectrocatalytic CO2 reduction through meticulous interface and microenvironment tailoring and sets a benchmark for both Faradaic efficiency and current density in solar liquid fuel production.
- Research Organization:
- University of North Carolina at Chapel Hill, NC (United States)
- Sponsoring Organization:
- NSF National Nanotechnology Coordinated Infrastructure Program; USDOE Office of Science (SC), Basic Energy Sciences (BES)
- Grant/Contract Number:
- SC0021173
- OSTI ID:
- 2377747
- Journal Information:
- Journal of the American Chemical Society, Journal Name: Journal of the American Chemical Society Journal Issue: 3 Vol. 146; ISSN 0002-7863
- Publisher:
- American Chemical Society (ACS)Copyright Statement
- Country of Publication:
- United States
- Language:
- English
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