Pt nanoclusters on GaN nanowires for solar-asssisted seawater hydrogen evolution
Abstract
Seawater electrolysis provides a viable method to produce clean hydrogen fuel. To date, however, the realization of high performance photocathodes for seawater hydrogen evolution reaction has remained challenging. Here, we introduce n+-p Si photocathodes with dramatically improved activity and stability for hydrogen evolution reaction in seawater, modified by Pt nanoclusters anchored on GaN nanowires. We find that Pt-Ga sites at the Pt/GaN interface promote the dissociation of water molecules and spilling H* over to neighboring Pt atoms for efficient H2 production. Pt/GaN/Si photocathodes achieve a current density of −10 mA/cm2 at 0.15 and 0.39 V vs. RHE and high applied bias photon-to-current efficiency of 1.7% and 7.9% in seawater (pH = 8.2) and phosphate-buffered seawater (pH = 7.4), respectively. We further demonstrate a record-high photocurrent density of ~169 mA/cm2 under concentrated solar light (9 suns). Moreover, Pt/GaN/Si can continuously produce H2 even under dark conditions by simply switching the electrical contact. This work provides valuable guidelines to design an efficient, stable, and energy-saving electrode for H2 generation by seawater splitting.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jan 12, 2023
- Source ID
- 10.1038/s41467-023-35782-z
Entities
People
- Ishtiaque Ahmed Navid
- Ke R Yang
- Peng Zhou
- Victor S Batista
- Wan Jae Dong
- Yixin Xiao
- Zetian Mi
- Zhengwei Ye
Organizations
- United States Army
- University of Michigan