Perovskite/Perovskite Tandem Photoelectrodes For Low-Cost Unassisted Photoelectrochemical Water Splitting

Recipient University of Toledo (PI: Yanfa Yan)

Water Splitting Technology PEC

Abstract We propose to develop monolithically integrated perovskite/perovskite tandem photoelectrodes to achieve low-cost, high efficiency (solar-to-H2 efficiency (STH) up to 20%), and long-term stability (>1,000 hours) spontaneous water splitting systems. According to recent theoretical modeling, a tandem device consisting of a 1.80 eV wide bandgap (Eg) perovskite top photoelectrode and a 1.25 eV low-Eg mixed Pb-Sn perovskite bottom photoelectrode can yield a STH efficiency of >20%. The perovskite/perovskite tandem photoelectrodes can be fabricated by low-cost low-temperature solution processes on conductive flexible inexpensive stainless steel (SS) substrates, presenting a significant technoeconomic advantage over the state-of-the-art spontaneous water splitting devices such as InGaP/GaAs and InGaP/InGaAs tandem photoelectrodes. This project will also leverage the extensive materials characterization and device measurement expertise at NREL (node of the HydoGEN EMN consortium).