|
|
Kumar, M. P., Sasikumar, M., Arulraj, A., Rajasudha, V., Murugadoss, G., Kumar, M. R., et al. (2022). NiFe Layered Double Hydroxide Electrocatalyst Prepared via an Electrochemical Deposition Method for the Oxygen Evolution Reaction. Catalysts, 12(11), 1470.
Abstract: Herein, we aimed to obtain NiFe layered double hydroxide (LDH) with a controlled phase and surface morphology as a highly active and stable oxygen evolution catalyst via the electrochemical deposition method, which was thermodynamically stable for the oxygen evolution reaction (OER) in an alkaline medium. The NiFe-LDH sample was analyzed by sophisticated instruments and tested as an electrocatalyst on Toray carbon (TC). The NiFe-LDH electrocatalyst showed an excellent performance with lower overpotential of 0.27 V at 35 mA cm(-2) and higher density of 125 mA cm(-2) for OER in the 1 M KOH electrolyte solution. Moreover, the prepared catalyst exhibited unpredictable long-time stability for 700 h. From our knowledge, NiFe-LDH is a robust highly stable electrocatalyst compared to the recent reports.
|
|
|
|
Rendon, R. C., Salvo, C., Sepulveda, E., Arulraj, A., Sanhueza, F., Rodriguez, J. J., et al. (2022). Evaluation of Structural and Functional Properties of La0.6Sr0.4MnO3 Perovskite Prepared by the Fast Solution Combustion Approach. Catalysts, 12(12), 1636.
Abstract: A series of La0.6Sr0.4MnO3 (LSM) perovskite was made using the rapid solution combustion method, which was calcined by varying the temperatures. In order to determine how the calcination temperature affected the nanopowders produced and calcined at various temperatures, their microstructural, morphological, compositional, optical, and electrical properties were analyzed using corresponding characterization tools. The XRD results showed the coexistence of the rhombohedral polymorphs R-3c and Pm-3m for the perovskite phase under a calcination temperature of 1400 degrees C, which were eliminated with increased calcination temperature. The average grain size was found to increase with increasing calcination temperature. The EDS analysis showed better agreement of the stoichiometry with the theoretical composition. The apparent porosity decreased with increasing temperature due to the coalescence of sintering pores. The sample obtained after calcination at 1500 degrees C showed 10.3% porosity. The hardness also improved with increasing calcination temperature and reached a maximum value of 0.4 GPa, which matched the bulk density. A similar trend was observed in the resistivity studies as a function of temperature, and all the samples exhibited a low resistivity of similar to 1.4 Omega.cm in the temperature range of 500-600 degrees C. The optical characterization showed broad absorption at 560-660 nm and bandwidth values between 3.70 and 3.95 eV, according to the applied heat treatment.
|
|
