Hydrogen generation from metal chloride doped sodium-borohydride by thermolysis at low temperature: The effect of material preparation methods

Abstract

NaBH4 /additive materials were synthesized using the facile solution, wet ball-milling, and dry ball-milling methods. The materials 10(additives)/NaBH4 (additives = MgCl2, CaCl2, MnCl2, FeCl2, NiCl2 and ZnCl2) were also prepared by Facile solution method. Thermolysis using a flow reactor studied the synthesized materials for hydrogen generation. The synthesized materials’ properties were evaluated by using the X-ray diffraction, TGA, FE-SEM, Particle Size Distribution (PSD), Raman spectroscopy, and Fourier Transform Infrared spectroscopy characterize (FTIR). The additive/catalyst optimum-loading was found to be 30 wt%, 50 wt%, and 50 wt% of CaCl2 for hydrogen generation from sodium-borohydride for the facile solution, wet ball-milling, and dry ball milling method, respectively. Adding additives, CaCl2 decreased the activation energy for the thermolysis of NaBH4 at 100 oC. This resulted in increased generation of hydrogen at 100 oC. The generation of hydrogen was ∼3.68 wt% with 50CaCl2/NaBH4 (WBM)> ∼3.63 wt% 50CaCl2/NaBH4 (DBM)> ∼1.74 wt% with 30CaCl2/NaBH4 (FS) at 100 ℃. The study suggests that the synthesis method plays an important role in the thermolysis reaction for hydrogen generation, and the wet ball-milling method was the most suitable.