Amorphous Si thin film based photocathodes with high photovoltage for efficient hydrogen production.
An amorphous Si thin film with TiO2 encapsulation layer is demonstrated as a highly promising and stable photocathode for solar hydrogen production. With platinum as prototypical cocatalyst, a photocurrent onset potential of 0.93 V vs RHE and saturation photocurrent of 11.6 mA/cm(2) are measured. Importantly, the a-Si photocathodes exhibit impressive photocurrent of ~6.1 mA/cm(2) at a large positive bias of 0.8 V vs RHE, which is the highest for all reported photocathodes at such positive potential. Ni-Mo alloy is demonstrated as an alternative low-cost catalyst with onset potential and saturation current similar to those obtained with platinum. This low-cost photocathode with high photovoltage and current is a highly promising photocathode for solar hydrogen production.
Electrical Engineering and Computer Sciences, University of California , Berkeley, California 94720, United States.
Yongjing
Y
Lin
Corsin
C
Battaglia
Mathieu
M
Boccard
Mark
M
Hettick
Zhibin
Z
Yu
Christophe
C
Ballif
Joel W
JW
Ager
Ali
A
Javey
D002384:Catalysis; D004566:Electrodes; D006859:Hydrogen / Q000737:chemistry*; D010984:Platinum / Q000737:chemistry; D012825:Silicon / Q000737:chemistry*; D012993:Solar Energy; D013472:Sunlight; D014025:Titanium / Q000737:chemistry
C009495:titanium dioxide; D010984:Platinum; D006859:Hydrogen; D014025:Titanium; D012825:Silicon