Methane oxidation to ethanol by a molecular junction photocatalyst

Jijia Xie; Cong Fu; Matthew G Quesne; Jian Guo; Chao Wang; Lunqiao Xiong; Christopher D Windle; Srinivas Gadipelli; Zheng Xiao Guo; Weixin Huang; C Richard A Catlow; Junwang Tang

doi:10.1038/s41586-025-08630-x

Methane oxidation to ethanol by a molecular junction photocatalyst

Nature. 2025 Jan 20. doi: 10.1038/s41586-025-08630-x. Online ahead of print.

Authors

Jijia Xie¹, Cong Fu², Matthew G Quesne^{3

4}, Jian Guo⁵, Chao Wang¹, Lunqiao Xiong^{1

6}, Christopher D Windle¹, Srinivas Gadipelli⁵, Zheng Xiao Guo^{7

8}, Weixin Huang⁹, C Richard A Catlow^{10

11}, Junwang Tang^{12

13}

Affiliations

¹ Department of Chemical Engineering, University College London, London, UK.
² Key Laboratory of Precision and Intelligent Chemistry, iChEM, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, China.
³ School of Chemistry, University of Cardiff, Park Place, Cardiff, UK.
⁴ School of Chemistry, University of Leeds, Leeds, UK.
⁵ Department of Chemistry, University College London, London, UK.
⁶ Industrial Catalysis Center, Department of Chemical Engineering, Tsinghua University, Beijing, China.
⁷ Department of Chemistry, University College London, London, UK. [email protected].
⁸ Department of Chemistry, The University of Hong Kong, Hong Kong SAR, China. [email protected].
⁹ Key Laboratory of Precision and Intelligent Chemistry, iChEM, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, China. [email protected].
¹⁰ School of Chemistry, University of Cardiff, Park Place, Cardiff, UK. [email protected].
¹¹ Department of Chemistry, University College London, London, UK. [email protected].
¹² Department of Chemical Engineering, University College London, London, UK. [email protected].
¹³ Industrial Catalysis Center, Department of Chemical Engineering, Tsinghua University, Beijing, China. [email protected].

PMID: 39832717
DOI: 10.1038/s41586-025-08630-x

Abstract

Methane, the major component of natural and shale gas, is a significant carbon source for chemical synthesis. The direct partial oxidation of methane to liquid oxygenates under mild conditions^1-3 is an attractive pathway, but the molecule's inertness makes it challenging to achieve simultaneously high conversion and high selectivity towards a single target product. This difficulty is amplified when aiming for more valuable products that require C-C coupling^4,5. While selective partial methane oxidation processes^1-3,6-9 have thus typically generated C₁ oxygenates^6,7, recent reports have documented photocatalytic methane conversion to the C₂ oxygenate ethanol with low conversions but good to high selectivities^4,5,8-12. Here, we show that the intramolecular junction photocatalyst CTF-1 with alternating benzene and triazine motifs^7,13 drives methane coupling and oxidation to ethanol with a high selectivity and much improved conversion. The heterojunction architecture not only enables efficient and long-lived separation of charges after their generation, but also preferential adsorption of H₂O and O₂ to the triazine and benzene units, respectively. This dual-site feature separates C-C coupling to form ethane intermediates from the sites where •OH radicals are formed and thereby avoids overoxidation. When loaded with Pt to boost performance further, the molecular heterojunction photocatalyst generates ethanol in a packed-bed flow reactor with improved conversion that results in an apparent quantum efficiency of 9.4%. We anticipate that further developing the "intramolecular junction" approach will deliver efficient and selective catalysts for C-C coupling, pertaining, but not limited, to methane conversion to C₂₊ chemicals.