Electrochemical investigation and modelling of LaNi4.77Al0.23 thin-films sputtered on glass wafers

Abstract

In the present work, we report on the microfabrication of metal hydride thin-film electrodes which can be utilized for rechargeable microbatteries or sensor applications. A multi-layer deposition technique is developed based on physical vapor deposition to fabricate the thin-film electrodes on a glass substrate. The morphology and the structure of the thin-film electrodes are studied by using Field Emission Scanning Electron Microscopy coupled with an Energy Dispersive Spectroscopy module. The surface composition of the thin-film electrodes are determined using X-ray Photoelectron Spectroscopy. Cyclic Voltammetry and galvanostatic charge-discharge measurements are performed to obtain insights into the electrochemical performance of the electrodes. Finally, a semi-empirical model is derived which allows for the determination of the equilibrium potential of the electrode as a function of its hydrogen content.

Modification of Hydrogenation and Corrosion Properties of Hydrogen Storage Material by Amorphous TiCrFeCoNi HEA Layer

“…The deposition of intermetallic alloy films (including HEAs) has been reported using various physical vapour deposition (PVD) techniques such as pulsed laser deposition, laser cladding, ion sputtering, ion plating, RF-magnetron sputtering, or flash evaporation-deposition [ 6 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Amongst multicomponent thin films on different alloy substrates and powders are also thin films of hydrogen storage materials (HSMs, e.g., LaNi 5 type) on different substrates [ 13 , 19 , 20 , 21 , 22 ].…”

“…The deposition of intermetallic alloy films (including HEAs) has been reported using various physical vapour deposition (PVD) techniques such as pulsed laser deposition, laser cladding, ion sputtering, ion plating, RF-magnetron sputtering, or flash evaporation-deposition [ 6 , 13 , 14 , 15 , 16 , 17 , 18 , 19 ]. Amongst multicomponent thin films on different alloy substrates and powders are also thin films of hydrogen storage materials (HSMs, e.g., LaNi 5 type) on different substrates [ 13 , 19 , 20 , 21 , 22 ]. The utilisation of sputtered intermetallic thin films of HSMs is considered beneficial because of their higher thermal conductivity, improved resistance to hydrogen pulverisation, and high efficiency of protective and catalytic layers as compared with their bulk counterparts [ 13 , 19 , 23 , 24 ].…”

“…Amongst multicomponent thin films on different alloy substrates and powders are also thin films of hydrogen storage materials (HSMs, e.g., LaNi 5 type) on different substrates [ 13 , 19 , 20 , 21 , 22 ]. The utilisation of sputtered intermetallic thin films of HSMs is considered beneficial because of their higher thermal conductivity, improved resistance to hydrogen pulverisation, and high efficiency of protective and catalytic layers as compared with their bulk counterparts [ 13 , 19 , 23 , 24 ]. The crystallinity and capacity of the PVD thin films depend on the type of goal, kind of substrate, and sputter parameters.…”

“…The sputtered films of HSMs are usually amorphous and generally show about two times lower capacities than the respective bulk crystalline alloys. Some of the authors think that this is due to the restricted volume expansion within the film since a peeled-off film could absorb almost the same amount of hydrogen [ 13 , 20 , 23 ]…”