Photoelectrocatalytic reduction of CO2 to methanol over a photosystem II-enhanced Cu foam/Si-nanowire system


Zichao Lian , Donglai Pan , Wenchao Wang , Dieqing Zhang , Guisheng Li , Hexing Li

DOI:10.1016/j.jes.2016.12.018

Received October 12, 2016,Revised December 13, 2016, Accepted , Available online October 23, 2017

Volume 60,2017,Pages 108-113

A solar-light double illumination photoelectrocatalytic cell (SLDIPEC) was fabricated for autonomous CO2 reduction and O2 evolution with the aid of photosystem II (PS-II, an efficient light-driven water-oxidized enzyme from nature) and utilized in a photoanode solution. The proposed SLPEC system was composed of Cu foam as the photoanode and p-Si nanowires (Si-NW) as the photocathode. Under solar irradiation, it exhibited a super-photoelectrocatalytic performance for CO2 conversion to methanol, with a high evolution rate (41.94 mmol/hr), owing to fast electron transfer from PS-II to Cu foam. Electrons were subsequently trapped by Si-NW through an external circuit via bias voltage (0.5 V), and a suitable conduction band potential of Si (?0.6 eV) allowed CO2 to be easily reduced to CH3OH at the photocathode. The constructed Z-scheme between Cu foam and Si-NW can allow the SLDIPEC system to reduce CO2 (8.03 mmol/hr) in the absence of bias voltage. This approach makes full use of the energy band mismatch of the photoanode and photocathode to design a highly efficient device for solving environmental issues and producing clean energy.

Copyright © Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights reserved. 京ICP备05002858号-3