A mechanistic study of molecular CO2 interaction and adsorption on carbon implanted SnS2 thin film for photocatalytic CO2 reduction activity
Journal
Nano Energy
Journal Volume
72
Journal Issue
104717
Pages
1-10
Date Issued
2020
Author(s)
Billo, T.
Shown, I.
Anbalagan, A.K.
Effendi, T.A.
Sabbah, A.
Fu, F.-Y.
Chu, C.-M.
Woon, W.-Y.
Chen, R.-S.
Lee, C.-H.
Chen, K.-H.
Abstract
Gas-phase photocatalytic reactions to convert carbon dioxide and water into oxygen and hydrocarbons are the foundation of life on earth. However, the efficiency of photosynthesis is relatively low (~1%), which leaves much room for artificial photosynthesis to reach the benchmark of the solar cells (>15%). In this work, carbon implanted SnS2 thin films (C–SnS2) were prepared to study photocatalytic activity and adsorbate-catalyst surface interactions during CO2 photoreduction. The electron density distribution in C–SnS2 and its contribution toward the photogenerated charge transfer process has been analyzed by the angle-dependent X-ray absorption near-edge structure (XANES) study. The C–SnS2 surface affinity toward the CO2 molecule was monitored by in-situ dark current and Raman spectroscopy measurements. By optimizing the dose during ion implantation, SnS2 thin film with 1 wt% carbon incorporation shows 108 times enhancement in the CO2 conversion efficiency and more than 89% product selectivity toward CH4 formation compared with the as-grown SnS2 without carbon incorporation. The improved photocatalytic activity can be ascribed to enhanced light harvesting, pronounced charge-transfer between SnS2 and carbon with improved carrier separation and the availability of highly active carbon sites that serve as favorable CO2 adsorption sites.
Publisher
Elsevier Ltd
Type
journal article