High-Photovoltage Silicon Nanowire for Biological Cofactor Production

• DOI: 10.1021/jacs.3c06243
• Publication Date: 2023-08-31T20:13:00Z
• Authors: Elizabeth Lineberry; Jinhyun Kim; Jimin Kim; Inwhan Roh; Jia-An Lin; Peidong Yang
• Keywords: Climate Action; Silicon; Benchmarking; Engineering; Affordable and Clean Energy; Chemical sciences; Nanowires; Chemical Sciences; General Chemistry; NAD; 7. Clean energy; Nanostructures

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.