Photothermal dry reforming of ethanol over rod-like Ni/ZrO2 catalysts

Photo-assisted ethanol dry reforming (EDR) for syngas production was deeply studied over nanorod-like Ni/ZrO2 catalyst synthesized by precipitation and impregnation technique, respectively. The effect of light irradiation as well as catalyst preparation method on EDR reaction was investigated in detail with the stoichiometric feed ratios, over a temperature region of 350 to 550 °C. Photo-enhancement factor of ethanol conversion greatly increased from 10% (dark) to 40% (light) together with less formation of byproducts. Moreover, the experimental results depicted the better performance of P-Ni/ZrO2 catalyst due to its abundant oxygen vacancies and strong Ni-Zr interaction. Enriched interfacial oxygen defects and more light-excited electrons facilitated the activation/dissociation of ethanol and CO2, thereby enhancing the catalytic activity. In addition, the mean particle size of NiO in P-Ni/ZrO2 was (10.3 nm) which was smaller than that of the I-Ni/ZrO2 (16.5 nm), suggesting its higher dispersion of active metal. The calculated apparent activation energy of P-Ni/ZrO2 was 20.6 eV which was much less than the value of I-Ni/ZrO2 (37.7 eV). This work might provide the valuable insight for the development of highly-efficient photothermal catalyst to enhance the value-added utilization of greenhouse gas CO2.