Synthesis and multi-technique characterization of nickel loaded MCM-41 as potential hydrogen-storage materials

Abstract

Ni/MCM-41 samples have been successfully prepared by wet impregnation method with different degrees of metal loading. Various techniques including X-ray diffraction, N2 adsorption?desorption, transmission electron microscopy, inductively coupled plasma atomic emission spectroscopy, electron microprobe analysis, UV?Vis diffuse reflectance spectra, infrared analysis, adsorption of pyridine coupled to infrared spectroscopy and hydrogen adsorption at 77 K at high and low pressure conditions were employed for the materials characterization. The Ni loading degree had a marked influence on the structural, chemical, acid and hydrogen storage properties of the samples. Thus, a low Ni loading favors the presence of highly dispersed Ni species responsible of the Lewis acidity. These species would promote hydrogen-favorable sites leading to a positive effect on the hydrogen storage capacity.