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Published on: June 12, 2019
Ti3+-O Acid-Base Pairs for Efficient Solar-Driven Photothermal Nonoxidative Ethane Dehydrogenation
Yuwen Sun1,2, Kun Gong1, Tianyu Li3
1Center of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai201210, China.
Journal of the American Chemical Society
|July 16, 2026
Summary
Noble metal-free catalysts featuring Ti3+-O acid-base pairs on reduced rutile TiO2 enable efficient solar-driven nonoxidative ethane dehydrogenation (NOEDH) for ethene production without external heating.
Area of Science:
- Catalysis
- Materials Science
- Renewable Energy
Background:
- Nonoxidative ethane dehydrogenation (NOEDH) is an efficient route for ethene production but requires severe thermodynamic conditions.
- Solar-driven NOEDH is a sustainable alternative, but achieving high activity and selectivity with noble metal-free catalysts without external heating is challenging.
Purpose of the Study:
- To develop a noble metal-free catalyst for efficient solar-driven nonoxidative ethane dehydrogenation (NOEDH) without external heating.
- To investigate the role of surface Ti3+-O acid-base pairs in enhancing catalytic performance.
Main Methods:
- Synthesis of reduced rutile TiO2 catalysts with varying reduction temperatures.
- Characterization using techniques like X-ray diffraction, X-ray photoelectron spectroscopy, and UV-Vis spectroscopy.
- Evaluation of catalytic performance for NOEDH under full-spectrum solar irradiation.
Main Results:
- Optimally reduced TiO2 (750 °C) exhibited an ethene production rate of 392.0 mmol g-1 h-1, 1107 times higher than pristine TiO2.
- Achieved high ethene selectivity (94.9%) surpassing the thermodynamic equilibrium limit.
- Identified surface Ti3+-O Lewis acid-base pairs as crucial for enhanced light absorption, charge carrier separation, and C-H bond activation.
- Demonstrated reduced apparent activation energy from 157.6 kJ mol-1 to 75.0 kJ mol-1 under illumination.
Conclusions:
- Surface Ti3+-O acid-base pairs on reduced rutile TiO2 are highly effective for solar-driven NOEDH.
- This catalyst system offers a promising pathway for sustainable and efficient ethene production.
- The study highlights the potential of noble metal-free catalysts for light-driven alkane upgrading.
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