Heterostructure Engineering of a Reverse Water Gas Shift Photocatalyst

Hong Wang; Jia Jia; Lu Wang; Keith Butler; Rui Song; Gilberto Casillas; Le He; Nazir P Kherani; Doug D Perovic; Liqiang Jing; Aron Walsh; Roland Dittmeyer; Geoffrey A Ozin

doi:10.1002/advs.201902170

Heterostructure Engineering of a Reverse Water Gas Shift Photocatalyst

Adv Sci (Weinh). 2019 Oct 4;6(22):1902170. doi: 10.1002/advs.201902170. eCollection 2019 Nov.

Authors

Hong Wang¹, Jia Jia^{2

3}, Lu Wang^{2

4}, Keith Butler⁵, Rui Song², Gilberto Casillas⁶, Le He⁴, Nazir P Kherani³, Doug D Perovic³, Liqiang Jing⁷, Aron Walsh^{8

9}, Roland Dittmeyer¹⁰, Geoffrey A Ozin²

Affiliations

¹ Key Laboratory of Functional Polymer Materials of the Ministry of Education Institute of Polymer Chemistry College of Chemistry Nankai University Tianjin 300071 P. R. China.
² Materials Chemistry and Nanochemistry Research Group Solar Fuels Cluster Departments of Chemistry University of Toronto 80 St. George Street Toronto ON M5S3H6 Canada.
³ Department of Materials Science and Engineering University of Toronto 184 College Street Toronto ON M5S3E4 Canada.
⁴ Institute of Functional Nano & Soft Materials (FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices Soochow University 199 Ren'ai Road Suzhou Jiangsu P. R. China.
⁵ SciML, Scientific Computing Department, Rutherford Appleton Laboratory Didcot OX110QX UK.
⁶ UOW Electron Microscopy Centre, University of Wollongong Wollongong New South Wales 2500 Australia.
⁷ Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Science International Joint Research Center for Catalytic Technology Heilongjiang University Harbin 150080 P. R. China.
⁸ Department of Materials, Imperial College London Exhibition Road London SW7 2AZ UK.
⁹ Department of Materials Science and Engineering, Yonsei University Seoul 03722 Korea.
¹⁰ Institute for Micro Process Engineering, Karlsruhe Institute of Technology Hermann-von-Helmholtz-Platz 1 76344 Eggenstein-Leopoldshafen Germany.

Abstract

To achieve substantial reductions in CO₂ emissions, catalysts for the photoreduction of CO₂ into value-added chemicals and fuels will most likely be at the heart of key renewable-energy technologies. Despite tremendous efforts, developing highly active and selective CO₂ reduction photocatalysts remains a great challenge. Herein, a metal oxide heterostructure engineering strategy that enables the gas-phase, photocatalytic, heterogeneous hydrogenation of CO₂ to CO with high performance metrics (i.e., the conversion rate of CO₂ to CO reached as high as 1400 µmol g cat^-1 h^-1) is reported. The catalyst is comprised of indium oxide nanocrystals, In₂O_3- _x (OH) _y , nucleated and grown on the surface of niobium pentoxide (Nb₂O₅) nanorods. The heterostructure between In₂O_3- _x (OH) _y nanocrystals and the Nb₂O₅ nanorod support increases the concentration of oxygen vacancies and prolongs excited state (electron and hole) lifetimes. Together, these effects result in a dramatically improved photocatalytic performance compared to the isolated In₂O_3- _x (OH) _y material. The defect optimized heterostructure exhibits a 44-fold higher conversion rate than pristine In₂O_3- _x (OH) _y . It also exhibits selective conversion of CO₂ to CO as well as long-term operational stability.

Keywords: CO2 conversion; charge transfer; heterostructures; photocatalysts; semiconductors.