Sol-Gel auto-combustion synthesis and physicochemical properties of BaAl2O4 nanoparticles; electrochemical hydrogen storage performance and density functional theory

Abstract

Spinel BaAl2O4 nanopowders were synthesized via an aqueous combustion using stoichiometric amount of cations, Ba2+ and Al3+, in rational fraction of a fuel (maltose). In order to achieve pure crystals, single fuel led to the formation of combustion reaction. The structural analysis indicates that the concentration of the starting materials and annealing temperature directly affect the purity of the product. The Scherrer and Hall-Williamson equation were performed to measure the average crystallite sizes of the BaAl2O4 nanopowders in the range of 26.5 and 40.8 nm, respectively. The microscopic analysis, SEM and TEM, were indicated the morphology and the nanoscale formation of BaAl2O4 ranging from 30 to 40 nm. The Band gap energy was calculated using Tauc method obtained at 3.34 eV. The maximum discharge capacity of BaAl2O4 obtained at 1000 mAh/g after 15 cycles. This result was also confirmed by theoretical calculation.