Laser-assisted synthesis of bentonite/Pd nanocomposite and its electrochemical hydrogen storage capacity

Abstract

Today, the increasing world population has led to increased consumption of fossil fuels for energy production, causing environmental problems. Hydrogen with high energy density can be used as a suitable alternative to fossil fuel sources. Hydrogen atoms can be stored on porous structures by physical interaction. Hence, simple and eco-friendly approaches have been taken to prepare bentonite/Pd nanocomposites for electrochemical hydrogen storage. Laser ablation in the deionized water medium was employed as a physical route for the synthesis of Pd nanoparticles (NPs). Bentonite, a porous substrate with a high surface area of 47 m2/g, was employed for the deposition of Pd NPs via physical mixing. The morphological study of nanocomposite indicated that the spherically shaped Pd NPs with a diameter of 20–27 nm are successfully deposited on the bentonite substrate. The as-prepared nanocomposites were loaded on stainless steel electrode through drop-casting and their hydrogen storage capacity was determined via cyclic voltammetry (CV). The CV measurement of the B/Pdx electrodes (x is laser ablation times of 15, 30, 45, and 60 min) in 1.0 M KOH electrolyte at the scan rate of 100 mV/s at room temperature demonstrated good hydrogen storage capacity (37 C/g) and stability during 200 scans.