The spinel LiMnO (LMO) is a promising cathode material for rechargeable Li-ion batteries due to its excellent properties, including cost effectiveness, eco-friendliness, high energy density, and rate capability. The commercial application of LiMnO is limited by its fast capacity fading during cycling, which lowers the electrochemical performance. In the present work, phase-pure and crystalline LiMnO spinel in the nanoscale were synthesized using single flame spray pyrolysis via screening 16 different precursor-solvent combinations.
View Article and Find Full Text PDFDynamic impedance spectroscopy is one of the most powerful techniques in the qualitative and quantitative mechanistic studies of electrochemical systems, as it allows for time-resolved investigation and dissection of various physicochemical processes occurring at different time scales. However, due to high-frequency artefacts connected to the non-ideal behaviour of the instrumental setup, dynamic impedance spectra can lead to wrong interpretation and/or extraction of wrong kinetic parameters. These artefacts arise from the non-ideal behaviour of the voltage and current amplifier (I/E converters) and stray capacitance.
View Article and Find Full Text PDFDynamic multi-frequency analysis (DMFA) is capable of acquiring high-quality frequency response of electrochemical systems under non-stationary conditions in a broad range of frequencies. In this work, we used DMFA to study the kinetics of (de-)intercalation of univalent cations (Na and K) in thin films of nickel hexacyanoferrate (NiHCF) during cyclic voltammetry. For this system, the classic stationary electrochemical impedance spectroscopy fails due to the instability of the oxidized form of NiHCF.
View Article and Find Full Text PDFReversible mixed-ion intercalation in nonselective host structures has promising applications in desalination, mixed-ion batteries, wastewater treatment, and lithium recovery through electrochemical ion pumping. One class of host compound that possesses many of the requirements needed for such applications (cost effectiveness, fast ion kinetics, and stability in an aqueous medium) includes the Prussian blue derivatives. Herein, the fundamental process of intercalation of multiple cations is studied at the thermodynamic level by means of galvanostatic cycling.
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