Highly Stable Spinel Oxide Cathode for Rechargeable Li–O₂ Batteries in Non-Aqueous Liquid and Gel-Based Electrolytes

Abstract

Metal−air batteries are receiving interest as they provide higher theoretical specific energy compared to the commercial lithium-ion batteries with two interacalation electrodes. In this, lithium−oxygen (Li−O 2 ) batteries are among the most promising candidates for the electrical vehicles because of their ability in holding the large amount of energy density by reacting with atmospheric air oxygen as the cathode reactant. The few problems that need to be overcome for the use of these batteries are capacity fading by the accumulation of discharge products (e.g., Li 2 O 2 ) on the electrode and stagnant electrode reactions. Hence, here, we synthesized a lowcost bimetallic spinel oxide NiFe 2 O 4 electrocatalyst via a simple modified hydrothermal method for Li−O 2 batteries as the cathode material in non-aqueous liquid and polymer gel electrolytes. The bifunctional NiFe 2 O 4 catalyst exhibited a high discharge capacity, better cyclic stability (100 cycles at current densities up to 1500 mA g −1 and constant capacities of 1000 and 500 mA h g −1 ) and low overpotential. The enhanced performance of the battery is due to the presence of the multivalent bimetallic Ni and Fe metals in the catalyst.

Nickel‐Based Materials for Advanced Rechargeable Batteries

“…Notably, for NiS x , the particle size can decrease with increasing S/Ni molar ratio, and NiS 2 nanospheres with surface enriched Ni 3+ active sites may exhibit the best catalytic activities compared with that of NiS and Ni 3 S 4 . [336] Besides, bimetallic spinel oxides, such as, NiFe 2 O 4 [328,337] and NiCo 2 O 4 , [338] with two pairs of redox centers that may provide good electrocatalytic activity. Using conductive materials, such as, CNTs, [339] carbon cloth, [340] and MXene, [50] to bridge these oxide catalysis has been reported to increase the volume of catalysis via a conductive and large surface area platform.…”

“…Besides, bimetallic spinel oxides, such as, NiFe 2 O 4 [ 328,337 ] and NiCo 2 O 4 , [ 338 ] with two pairs of redox centers that may provide good electrocatalytic activity. Using conductive materials, such as, CNTs, [ 339 ] carbon cloth, [ 340 ] and MXene, [ 50 ] to bridge these oxide catalysis has been reported to increase the volume of catalysis via a conductive and large surface area platform.…”

Effects of Aluminum Oxide Addition on Electrical and Mechanical Properties of 3 mol% Yttria-Stabilized Tetragonal Zirconia Electrolyte for IT-SOFCs

“…A solid oxide fuel cell (SOFC) is an electrochemical device that generates electrical energy via the simultaneous oxidation of fuel and reduction of oxygen, both of which are supplied from an external source [ 1 ]. Unlike galvanic cells, namely batteries [ 2 ], solid oxide fuels do not need to have energy stored in them before generating current, and therefore their operating time is not reduced in the same manner. It is sufficient to supply the required fuel.…”

Stabilizing Lithia-Based Cathodes through the In Situ Electrochemical Formation of an Inorganic MgF2 Interfacial Coating

“…The increasing demand for high-energy-density lithium-ion batteries (LIBs) by various industries has spurred the development of high-capacity cathode materials. − Despite the many advancements thus far, there is still room for improvement in the capacity of LIB cathode materials. In particular, the oxygen-related anionic redox reaction has been expected to provide important clues to significantly enhancing the cathode capacity. − The capacity of typical commercial cathode materials is based on the cationic redox reaction induced by heavy transition metals (Co, Ni, Mn, and Fe) in the structure.…”