Laser-nanostructured substrates for enhanced hydrogen evolution reaction

Abstract

In this work, we review our recent results demonstrating the effectiveness of pulsed laser irradiation to fabricate nanostructures on various substrates, which are then used to enhance the Hydrogen Evolution Reaction (HER).Femtosecond (fs) laser pulses were used to fabricate nanostructures directly on nickel and iron sheets, while nanosecond laser pulses were used to fabricate nanostructures on Ni foam (NF) substrates via pulsed laser deposition. Electrodeposition was further employed complementary to the fs laser-surface direct nanostructuring to deposit Ni nanoparticles on top of the laser-modified nanostructures. A thorough electrochemical, structural, and morphological comparison has been conducted between laser-nanostructured and flat (i.e., untreated) Ni and Fe electrodes. In addition, the Ni-deposited (with PLD) NF electrodes were compared to an untreated NF electrode. The prepared electrodes show enhanced electrochemical characteristics and superior performance in HER. Morevover, the laser-nanostructured and electrodeposited electrodes were found to be as much as 4.6 times more efficient in actual Hydrogen production conditions. We propose that scaling up in the fabrication of such nanostructured electrodes should be pursued to address global energy and environmental concerns.