Thermocatalytic nonoxidative ethane dehydrogenation (EDH) is a promising strategy for ethene production but suffers from intense energy consumption and poor catalyst durability; exploring technology that permits efficient EDH by solar energy remains a giant challenge. Herein, we present that an oxygen vacancy (Ov)-rich LaVO4 (LaVO4-Ov) catalyst is highly active and stable for photocatalytic EDH, through a dynamic lattice oxygen (Olatt.) and Ov co-mediated mechanism. Irradiated by simulated sunlight at mild conditions, LaVO4-Ov effectively dehydrogenates undiluted ethane to produce C2H4 and CO with a conversion of 2.3%. By loading a small amount of Pt cocatalyst, the evolution and selectivity of C2H4 are enhanced to 275 µmol h−1 g−1 and 96.8%. Of note, LaVO4-Ov appears nearly no carbon deposition after the reaction. The isotope tracked reactions reveal that the consumed Olatt. recuperates by exposing the used catalyst with O2, thus establishing a dynamic cycle of Olatt. and achieving a facile catalyst regeneration to preserve its intrinsic activity. The refreshed LaVO4-Ov exhibits superior reusability and delivers a turnover number of about 305. The Ov promotes photo absorption, boosts ethane adsorption/activation, and accelerates charge separation/transfer, thus improving the photocatalytic efficiency. The possible photocatalytic EDH mechanism is proposed, considering the key intermediates predicted by density functional theory (DFT) and monitored by in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS).
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |