On the microwave enhanced combustion synthesis of CuO-ZnO-Al2O3 nanocatalyst used in methanol steam reforming for fuel cell grade hydrogen production: Effect of microwave irradiation and fuel ratio

CuO-ZnO-Al2O3 nanocatalysts were synthesized by the microwave-assisted solution combustion method to produce hydrogen via the steam methanol reforming reaction. The influence of fuel/nitrates ratio and microwave irradiation was investigated. For this purpose, a series of CuO-ZnO-Al2O3 nanocatalysts were fabricated using different amounts of ethylene glycol as fuel in a microwave oven and a conventional furnace. The characteristic properties of prepared nanocatalysts were studied by X-ray diffraction, field emission electron microscope, specific surface area, energy dispersive X-ray and Fourier transform infrared spectroscopy analyses. The crystallography and morphology studies clarified that application of microwave oven instead of conventional furnace led to higher crystallinity of CuO and ZnO species and homogeneously smaller particles, respectively. Therefore, the surface area of sample synthesized in the microwave oven was higher than the other prepared in the furnace. The enhancement of fuel/nitrates ratio also increased specific surface area and dispersion of different species. Thus, with regards to significant physicochemical properties of the sample fabricated by the microwave assisted combustion method with fuel/nitrates ratio = 3, the catalytic experiments showed that it facilitated the methanol conversion even at low temperatures and its hydrogen and CO selectivity did not change severely during 1200 min under reaction conditions. (C) 2016 Elsevier Ltd. All rights reserved.