All Electrodeposited Nanowire Array Based Multi-Junction Photovoltaic Devices

Wednesday, 4 October 2017
Prince George's Exhibit Hall D/E (Gaylord National Resort and Convention Center)
W. Cheng, J. Lee (University of Iowa), G. Young (University of iowa), and S. Mubeen (University of Iowa)
Large-scale solar fuel production using semiconductor based photoelectrochemical system requires inexpensive, efficient and stable devices that can provide photovoltages sufficient to overcome both the thermodynamic and overpotential losses of the redox reaction. Here we report all electrodeposited multi-junction photovoltaic (PV) devices for solar fuel production using serially connected multiple Cd/CdSe/Au Schottky barrier junctions with photovoltages exceeding 1.0 V. These PV devices are synthesized inside nanoporous alumina membranes with each nanoscale solar conversion units physically and electronically isolated from each other, making the entire device fault tolerant. The alumina membranes also serves to protect the semiconductor from chemical and photoelectrochemical corrosion. Ensemble and individual nanowire measurements were performed to understand charge carrier energetics and transport pathways across multiple interfaces.