Direct Solar to Hydrogen Conversion

Direct solar-to-hydrogen conversion via inverted metamorphic multi-junction semiconductor architectures
Altmetric: 123Citations: 12More detail

Direct solar-to-hydrogen conversion via inverted metamorphic multi-junction semiconductor architectures
James L. Young, Myles A. Steiner, Henning Döscher, Ryan M. France, John A. Turner & Todd G. Deutsch
Nature Energy volume 2, Article number: 17028 (2017)

source Link:

Solar water splitting via multi-junction semiconductor photoelectrochemical cells provides direct conversion of solar energy to stored chemical energy as hydrogen bonds. Economical hydrogen production demands high conversion efficiency to reduce balance-of-systems costs. For sufficient photovoltage, water-splitting efficiency is proportional to the device photocurrent, which can be tuned by judicious selection and integration of optimal semiconductor bandgaps. Here, we demonstrate highly efficient, immersed water-splitting electrodes enabled by inverted metamorphic epitaxy and a transparent graded buffer that allows the bandgap of each junction to be independently varied. Voltage losses at the electrolyte interface are reduced by 0.55 V over traditional, uniformly p-doped photocathodes by using a buried p–n junction. Advanced on-sun benchmarking, spectrally corrected and validated with incident photon-to-current efficiency, yields over 16% solar-to-hydrogen efficiency with GaInP/GaInAs tandem absorbers, representing a 60% improvement over the classical, high-efficiency tandem III–V device. end quote.

References: see source link for more information including 35 reference papers.

Hydrogen is a high energy fuel which will grow in demand as the hydrogen economy develops along with relevant infrastructure. The prospect for solar plants to provide desalination and hydrogen production on site with a co-located hydrogen thermal power plant may be one means by which solar thermal and solar pv power may be augmented at night and in times of high demand by a diverse set of co located solar facilities including solar water desalination, direct solar hydrogen conversion, thermal solar power, solar pv power and hydrogen thermal power production. P. Langley