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Title: High-Photovoltage Silicon Nanowire for Biological Cofactor Production
Photocathodic conversion of NAD+ to NADH cofactor is a promising platform for activating redox biological catalysts and enzymatic synthesis using renewable solar energy. However, many photocathodes suffer from low photovoltage, consequently requiring a high cathodic bias for NADH production. Here, we report an n+p-type silicon nanowire (n+p-SiNW) photocathode having a photovoltage of 435 mV to drive energy-efficient NADH production. The enhanced band bending at the n+/p interface accounts for the high photovoltage, which conduces to a benchmark onset potential [0.393 V vs the reversible hydrogen electrode (VRHE)] for SiNW-based photocathodic NADH generation. In addition, the n+p-SiNW nanomaterial exhibits a Faradaic efficiency of 84.7% and a conversion rate of 1.63 μmol h–1 cm–1 at 0.2 VRHE, which is the lowest cathodic potential to achieve the maximum productivity among SiNW-sensitized cofactor production.  more » « less
Award ID(s):
2217161
PAR ID:
10507102
Author(s) / Creator(s):
; ; ; ; ;
Publisher / Repository:
Journal of American Chemical Society
Date Published:
Journal Name:
Journal of the American Chemical Society
Volume:
145
Issue:
36
ISSN:
0002-7863
Page Range / eLocation ID:
19508 to 19512
Subject(s) / Keyword(s):
Charge transfer,Light,Nanomaterials,Photonics,Redox reactions
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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