This study reports on the use of tetrabutylammonium dihydrogen trifluoride (TBAH 2 F 3 ) ionic liquid-based electrolytes in the aluminum (Al)−air battery system. The conductivity and activation energy of the electrolytes are reported alongside with electrochemical measurements and Al surface characterizations. The activation process of the Al surface is demonstrated and monitored in the ionic liquid-based electrolyte. The successful activation of the Al surface is obtained via the action of the H 2 F 3 − species present in the ionic liquid. The active species in the electrolyte are analyzed with the use of an attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy method, applied prior and subsequent to cell discharge. Primary Al−air cell evaluations with the use of different anodic discharge current loads, as well as different volume fractions of propylene carbonate (PC), were conducted. Using the electrochemical impedance spectroscopy (EIS) technique, we were able to monitor the wetting process of the air cathode. The use of TBAH 2 F 3 -based electrolytes resulted in high cell capacities (over 70% of the theoretical value). The results achieved and reported in this study are promising and present an additional option for an ionic liquid-based electrolyte for Al−air batteries.

Electrolysis of water to produce green and renewable hydrogen fuel is of great interest in clean energy field. water molecules can be decomposed to hydrogen and oxygen through catalysis. catalytic...

Hydrogen fuel is one of the most promising, renewable, and carbon-free alternatives to contaminating fossil fuels that are being used to date. Producing hydrogen by water splitting may not be efficient in some catalysts mainly due to the high overpotential that exists in forming oxygen, a half-reaction that occurs on the anode where water molecules are being oxidized. One of the best catalysts for the oxygen evolution reaction (OER) with a low overpotential is a unique two-dimensional bilayer system composed of monolayers of defected graphene and Fe-doped β-Ni­(OH)2. Here, we display by density functional theory how carbon vacancies and possible mechanical changes including sliding and twisting between layers of graphene//β-NiOOH affect the OER overpotential. Our results show that larger sliding energy between layers at an optimal concentration of carbon vacancies indicates better adhesion and electron transfer between the layers that consequently lowers the OER overpotential. This study contributes to understanding that finding improved two-dimensional catalysts for green hydrogen production could be achieved by designing interfaces with greater bonding and that sliding energy between the layers may serve as a control handle for engineering better catalysts.