title: Unbiased Sunlight-Driven Artificial Photosynthesis of Carbon Monoxide from CO2 Using a ZnTe-Based Photocathode and a Perovskite Solar Cell in Tandem.
abstract: Solar fuel production, mimicking natural photosynthesis of converting CO2 into useful fuels and storing solar energy as chemical energy, has received great attention in recent years. Practical large-scale fuel production needs a unique device capable of CO2 reduction using only solar energy and water as an electron source. Here we report such a system composed of a gold-decorated triple-layered ZnO@ZnTe@CdTe core-shell nanorod array photocathode and a CH3NH3PbI3 perovskite solar cell in tandem. The assembly allows effective light harvesting of higher energy photons (>2.14 eV) from the front-side photocathode and lower energy photons (>1.5 eV) from the back-side-positioned perovskite solar cell in a single-photon excitation. This system represents an example of a photocathode-photovoltaic tandem device operating under sunlight without external bias for selective CO2 conversion. It exhibited a steady solar-to-CO conversion efficiency over 0.35% and a solar-to-fuel conversion efficiency exceeding 0.43% including H2 as a minor product.
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, 37673 South Korea.
authors.forename: Youn Jeong
authors.initials: YJ
authors.lastname: Jang
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, 37673 South Korea.|Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology (KIST) , Seoul, 02792 South Korea.
authors.forename: Inyoung
authors.initials: I
authors.lastname: Jeong
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, 37673 South Korea.
authors.forename: Jaehyuk
authors.initials: J
authors.lastname: Lee
authors.affiliation: Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH) , Pohang, 37673 South Korea.
authors.forename: Jinwoo
authors.initials: J
authors.lastname: Lee
authors.affiliation: Photo-electronic Hybrids Research Center, Korea Institute of Science and Technology (KIST) , Seoul, 02792 South Korea.|KU-KIST Graduate School of Converging Science and Technology, Korea University , Seoul, 02841 South Korea.
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Ko
authors.affiliation: Department of Energy and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST) , 50 UNIST-gil, Ulsan, 44919 South Korea.
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Lee
keywords: CO2 reduction; ZnTe photocathode; artificial photosynthesis; perovskite solar cell; unbiased photoelectrochemical cell