Monolithic Photoelectrochemical Device for Direct Water Splitting with 19% Efficiency


Type
Article
Change log
Authors
Cheng, WH 
Richter, MH 
May, MM 
Ohlmann, J 
Lackner, D 
Abstract

Recent rapid progress in efficiencies for solar water splitting by photoelectrochemical devices has enhanced its prospects to enable storable renewable energy. Efficient solar fuel generators all use tandem photoelectrode structures, and advanced integrated devices incorporate corrosion protection layers as well as heterogeneous catalysts. Realization of near thermodynamic limiting performance requires tailoring the energy band structure of the photoelectrode and also the optical and electronic properties of the surface layers exposed to the electrolyte. Here, we report a monolithic device architecture that exhibits reduced surface reflectivity in conjunction with metallic Rh nanoparticle catalyst layers that minimize parasitic light absorption. Additionally, the anatase TiO2 protection layer on the photocathode creates a favorable internal band alignment for hydrogen evolution. An initial solar-to-hydrogen efficiency of 19.3 % is obtained in acidic electrolyte and an efficiency of 18.5 % is achieved at neutral pH condition (under simulated sunlight).

Description
Keywords
cond-mat.mtrl-sci, cond-mat.mtrl-sci
Journal Title
ACS Energy Letters
Conference Name
Journal ISSN
2380-8195
2380-8195
Volume Title
3
Publisher
American Chemical Society (ACS)