Selective CO Production by Photoelectrochemical Methane Oxidation on TiO2
Abstract
The inertness of the C–H bond in CH4 poses significant challenges to selective CH4 oxidation, which often proceeds all the way to CO2 once activated. Selective oxidation of CH4 to high-value industrial chemicals such as CO or CH3OH remains a challenge. Presently, the main methods to activate CH4 oxidation include thermochemical, electrochemical, and photocatalytic reactions. Of them, photocatalytic reactions hold great promise for practical applications but have been poorly studied. Existing demonstrations of photocatalytic CH4 oxidation exhibit limited control over the product selectivity, with CO2 as the most common product. The yield of CO or other hydrocarbons is too low to be of any practical value. In this work, we show that highly selective production of CO by CH4 oxidation can be achieved by a photoelectrochemical (PEC) approach. Under our experimental conditions, the highest yield for CO production was 81.9%. The substrate we used was TiO2 grown by atomic layer deposition (ALD), which features high concentrations of Ti3+ species. The selectivity toward CO was found to be highly sensitive to the substrate types, with significantly lower yield on P25 or commercial anatase TiO2 substrates. Moreover, our results revealed that the selectivity toward CO also depends on the applied potentials. Basedmore »
- Authors:
-
- Boston College, Chestnut Hill, MA (United States)
- Univ. of California, Riverside, CA (United States)
- Yale Univ., New Haven, CT (United States)
- Publication Date:
- Research Org.:
- Yale Univ., New Haven, CT (United States); Univ. of California, Riverside, CA (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES)
- OSTI Identifier:
- 1498722
- Grant/Contract Number:
- FG02-05ER15646; AC02-05CH11231
- Resource Type:
- Accepted Manuscript
- Journal Name:
- ACS Central Science
- Additional Journal Information:
- Journal Volume: 4; Journal Issue: 5; Journal ID: ISSN 2374-7943
- Publisher:
- American Chemical Society (ACS)
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
Citation Formats
Li, Wei, He, Da, Hu, Guoxiang, Li, Xiang, Banerjee, Gourab, Li, Jingyi, Lee, Shin Hee, Dong, Qi, Gao, Tianyue, Brudvig, Gary W., Waegele, Matthias M., Jiang, De-en, and Wang, Dunwei. Selective CO Production by Photoelectrochemical Methane Oxidation on TiO2. United States: N. p., 2018.
Web. doi:10.1021/acscentsci.8b00130.
Li, Wei, He, Da, Hu, Guoxiang, Li, Xiang, Banerjee, Gourab, Li, Jingyi, Lee, Shin Hee, Dong, Qi, Gao, Tianyue, Brudvig, Gary W., Waegele, Matthias M., Jiang, De-en, & Wang, Dunwei. Selective CO Production by Photoelectrochemical Methane Oxidation on TiO2. United States. doi:10.1021/acscentsci.8b00130.
Li, Wei, He, Da, Hu, Guoxiang, Li, Xiang, Banerjee, Gourab, Li, Jingyi, Lee, Shin Hee, Dong, Qi, Gao, Tianyue, Brudvig, Gary W., Waegele, Matthias M., Jiang, De-en, and Wang, Dunwei. Mon .
"Selective CO Production by Photoelectrochemical Methane Oxidation on TiO2". United States. doi:10.1021/acscentsci.8b00130. https://www.osti.gov/servlets/purl/1498722.
@article{osti_1498722,
title = {Selective CO Production by Photoelectrochemical Methane Oxidation on TiO2},
author = {Li, Wei and He, Da and Hu, Guoxiang and Li, Xiang and Banerjee, Gourab and Li, Jingyi and Lee, Shin Hee and Dong, Qi and Gao, Tianyue and Brudvig, Gary W. and Waegele, Matthias M. and Jiang, De-en and Wang, Dunwei},
abstractNote = {The inertness of the C–H bond in CH4 poses significant challenges to selective CH4 oxidation, which often proceeds all the way to CO2 once activated. Selective oxidation of CH4 to high-value industrial chemicals such as CO or CH3OH remains a challenge. Presently, the main methods to activate CH4 oxidation include thermochemical, electrochemical, and photocatalytic reactions. Of them, photocatalytic reactions hold great promise for practical applications but have been poorly studied. Existing demonstrations of photocatalytic CH4 oxidation exhibit limited control over the product selectivity, with CO2 as the most common product. The yield of CO or other hydrocarbons is too low to be of any practical value. In this work, we show that highly selective production of CO by CH4 oxidation can be achieved by a photoelectrochemical (PEC) approach. Under our experimental conditions, the highest yield for CO production was 81.9%. The substrate we used was TiO2 grown by atomic layer deposition (ALD), which features high concentrations of Ti3+ species. The selectivity toward CO was found to be highly sensitive to the substrate types, with significantly lower yield on P25 or commercial anatase TiO2 substrates. Moreover, our results revealed that the selectivity toward CO also depends on the applied potentials. Based on the experimental results, we proposed a reaction mechanism that involves synergistic effects by adjacent Ti sites on TiO2. Spectroscopic characterization and computational studies provide critical evidence to support the mechanism. Furthermore, the synergistic effect was found to parallel heterogeneous CO2 reduction mechanisms. Our results not only present a new route to selective CH4 oxidation, but also highlight the importance of mechanistic understandings in advancing heterogeneous catalysis.},
doi = {10.1021/acscentsci.8b00130},
journal = {ACS Central Science},
number = 5,
volume = 4,
place = {United States},
year = {2018},
month = {4}
}
Web of Science
Figures / Tables:

Works referencing / citing this record:
Atomically Thin 2D Transition Metal Oxides: Structural Reconstruction, Interaction with Substrates, and Potential Applications
journal, October 2018
- Yang, Tong; Song, Ting Ting; Callsen, Martin
- Advanced Materials Interfaces, Vol. 6, Issue 1
Atomically Thin 2D Transition Metal Oxides: Structural Reconstruction, Interaction with Substrates, and Potential Applications
journal, October 2018
- Yang, Tong; Song, Ting Ting; Callsen, Martin
- Advanced Materials Interfaces, Vol. 6, Issue 1
CO oxidation over the polyoxometalate-supported single-atom catalysts M 1 /POM (Fe, Co, Mn, Ru, Rh, Os, Ir, and Pt; POM = [PW 12 O 40 ] 3– ): a computational study on the activation of surface oxygen species
journal, January 2019
- Liu, Chun-Guang; Zhang, Li-Long; Chen, Xue-Mei
- Dalton Transactions, Vol. 48, Issue 18
Figures / Tables found in this record: