Effect of different operational parameters on sol-gel synthesis and electrochemical hydrogen storage of FeVO4/Fe2V4O13 nanocomposites

• Saccharide assisted sol-gel synthesis of iron vanadate nanoparticles by changing operational parameters. • Effect of phase purity, microstrain, and particle size on electrochemical hydrogen storage capacity. • FeVO 4 /Fe 2 V 4 O 13 nanocomposites approvals maximum capacity of 601 mAhg -1 after 15 cycles. • Studying mechanism of electrochemical hydrogen storage in vanadate structures. Phase purity, morphology and physical characteristics are effective parameters which affect on the electrochemical behavior of electrode materials. So, iron vanadate materials (FV) synthesized through sol-gel method by changing different operational parameters such as molar ratio of Fe:V, amount of fuel and type of fuel (saccharide) to compare influence of different phase purity, microstrain and morphology on the energy storage ability of obtained samples. The FeVO 4 /Fe 2 V 4 O 13 nanocomposites (FV2) with particle size of 36 nm presents 601 mAhg -1 hydrogen storage capacity which is higher than pristine FeVO 4 (FV4) with capacity of 298 mAhg -1 after 15 cycles. The capacity of electrochemical hydrogen storage for diverse samples compared through chronopotentiometry charge discharge experiments in three-electrode cell with 2.0 M KOH electrolyte. The Williamson-Hall and Scherrer equations were utilized to determine the strain and size of the crystallites.