Promoted CO ₂ Reforming with Bioethanol over TiO ₂ -Supported Photothermal Catalysts

Reducing the greenhouse gas CO 2 in the atmosphere and converting it into high-value-added syngas is regarded as a competitive strategy in line with green and sustainable development. Herein, a series of M/TiO 2 (M = Cu, Co, Ni) catalysts were developed for photothermal CO 2 reduction with bioethanol, and the synergistic mechanism between photocatalysis and thermocatalysis was deeply investigated. Systematic characteristics and photothermal ethanol dry reforming (EDR) testing results revealed the relevancy between catalytic behavior and microstructure properties of TiO 2 -supported catalysts. Notably, the Ni/TiO 2 catalyst displayed superior catalytic behavior than Cu/TiO 2 and Co/TiO 2 counterparts, which mainly attributed to their abundant oxygen vacancies and stronger Ni–TiO 2 interaction. In addition, both the narrower band gap and higher light absorption ability directly promoted the Ni/TiO 2 catalyst possessing outstanding ethanol conversion (94.5%) and controllable H 2 /CO ratio (0.65) at 450 °C. Furthermore, the relatively less activation energy also determined that the Ni/TiO 2 sample possessed the fastest kinetic progression in the EDR process. Therefore, the Ni/TiO 2 catalyst exhibited the better photothermal catalytic activity compared with other 2 samples. We anticipate that photothermal synergy would offer good technical guidance to promote the conversion and utilization of greenhouse gas CO 2 under relatively low temperature environment.