Hydrogen production by methanol reforming catalyzed by copper gallium-based spinel using B-site doping strategy

Abstract

A series of B-site-doped copper spinel CuGaBO₄ (B = Co, Fe, Al, Ni) catalysts were synthesized and evaluated for methanol steam reforming (MSR). The surface morphology, elemental composition, and structural properties of the catalysts were characterized using x-ray diffractometer, scanning electron microscopy (SEM), energy dispersive spectroscopy, x-ray photoelectron spectrometer, and Brunner-Emmet-Teller (BET) surface area analysis. The SEM results reveal that the fresh catalysts consist of small particles stacked together, forming a porous structure with a particle size range of approximately 20–50 nm. BET analysis further confirms the presence of an ordered porous structure, which contributes to a higher BET surface area and pore volume. The O_1s spectrum reveals the presence of surface-adsorbed oxygen (O_ads), which helps to enhance catalytic activity and methanol conversion. In addition, it was found that the CuGaFeO₄ catalyst exhibited the highest methanol conversion at 90%, hydrogen production at 6.87 mmol/min/g_cat, and the CO selectivity was below 0.37%. After a subsequent 40 h stability test, the methanol conversion was still able to reach 85% and the hydrogen production was around 6 mmol/min/g_cat.