title: Tunable Syngas Production from CO2and H2O in an Aqueous Photoelectrochemical Cell.
abstract: Syngas, the mixture of CO and H2, is a key feedstock to produce methanol and liquid fuels in industry, yet limited success has been made to develop clean syngas production using renewable solar energy. We demonstrated that syngas with a benchmark turnover number of 1330 and a desirable CO/H2ratio of 1:2 could be attained from photoelectrochemical CO2and H2O reduction in an aqueous medium by exploiting the synergistic co-catalytic effect between Cu and ZnO. The CO/H2ratio in the syngas products was tuned in a large range between 2:1 and 1:4 with a total unity Faradaic efficiency. Moreover, a high Faradaic efficiency of 70 % for CO was acheived at underpotential of 180 mV, which is the lowest potential ever reported in an aqueous photoelectrochemical cell. It was found that the combination of Cu and ZnO offered complementary chemical properties that lead to special reaction channels not seen in Cu, or ZnO alone.
authors.affiliation: Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC, H3A 0E9, Canada.
authors.forename: Sheng
authors.initials: S
authors.lastname: Chu
authors.affiliation: Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC, H3A 0E9, Canada.
authors.forename: Shizhao
authors.initials: S
authors.lastname: Fan
authors.affiliation: Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC, H3A 0E9, Canada.
authors.forename: Yongjie
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L7, Canada.
authors.forename: David
authors.initials: D
authors.lastname: Rossouw
authors.affiliation: Department of Electrical Engineering and Computer Science, Center for Photonics and Multiscale Nanomaterials, University of Michigan, Ann Arbor, 1301 Beal Avenue, Ann Arbor, MI, 48105, USA.
authors.forename: Yichen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Department of Materials Science and Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario, L8S 4L7, Canada.
authors.forename: Gianluigi A
authors.initials: GA
authors.lastname: Botton
authors.affiliation: Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, QC, H3A 0E9, Canada. ztmi@umich.edu.|Department of Electrical Engineering and Computer Science, Center for Photonics and Multiscale Nanomaterials, University of Michigan, Ann Arbor, 1301 Beal Avenue, Ann Arbor, MI, 48105, USA. ztmi@umich.edu.
authors.forename: Zetian
authors.initials: Z
authors.lastname: Mi
keywords: CO2 reduction; Co-catalysts; energy conversion; semiconductors; solar fuel