Photocatalytic Reduction of CO 2 to Methanol by Cu 2 O/TiO 2 Heterojunctions

S.-P. Cheng, L.-W. Wei and H.-Paul Wang
Additional contact information
S.-P. Cheng: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan
L.-W. Wei: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan
H.-Paul Wang: Department of Environmental Engineering, National Cheng Kung University, Tainan 70101, Taiwan

Sustainability, 2021, vol. 14, issue 1, 1-11

Abstract: The conversion of CO 2 to low-carbon fuels using solar energy is considered an economically attractive and environmentally friendly route. The development of novel catalysts and the use of solar energy via photocatalysis are key to achieving the goal of chemically reducing CO 2 under mild conditions. TiO 2 is not very effective for the photocatalytic reduction of CO 2 to low-carbon chemicals such as methanol (CH 3 OH). Thus, in this work, novel Cu 2 O/TiO 2 heterojunctions that can effectively separate photogenerated electrons and holes were prepared for photocatalytic CO 2 -to-CH 3 OH. More visible light-active Cu 2 O in the Cu 2 O/TiO 2 heterojunctions favors the formation of methanol under visible light irradiation. On the other hand, under UV-Vis irradiation for 6 h, the CH 3 OH yielded from the photocatalytic CO 2 -to-CH 3 OH by the Cu 2 O/TiO 2 heterojunctions is 21.0–70.6 µmol/g-catalyst. In contrast, the yield of CH 3 OH decreases with an increase in the Cu 2 O fraction in the Cu 2 O/TiO 2 heterojunctions. It seems that excess Cu 2 O in Cu 2 O/TiO 2 heterojunctions may lead to less UV light exposure for the photocatalysts, and may decrease the conversion efficiency of CO 2 to CH 3 OH.

Keywords: photocatalysis; CO 2; Cu 2 O; TiO 2; p-n heterojunctions; methanol (search for similar items in EconPapers)
JEL-codes: O13 Q Q0 Q2 Q3 Q5 Q56 (search for similar items in EconPapers)
Date: 2021
References: View complete reference list from CitEc
Citations:

Downloads: (external link)
https://www.mdpi.com/2071-1050/14/1/374/pdf (application/pdf)
https://www.mdpi.com/2071-1050/14/1/374/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jsusta:v:14:y:2021:i:1:p:374-:d:714546

Access Statistics for this article

Sustainability is currently edited by Ms. Alexandra Wu

More articles in Sustainability from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().