Coaxial structures based on NiO/Ni@Carbon felt: Synthesis features, electrochemical behavior and application perspectives

Abstract

• Coaxial structures of NiO/Ni@Carbon felt were produced by electrochemical template synthesis. • By varying the temperature conditions, materials with different electrochemical behavior were synthesized. • The best temperature conditions are proposed for the electrochemical template synthesis of NiO/Ni@Carbon felt. The coaxial structures of NiO/Ni@Carbon felt were synthesized via an electrochemical template approach followed by annealing at various temperatures and exposure. Comparison of synthesis conditions, morphology features, as well as the results of measurements of electrochemical performance, made it possible to classify the application of the material by the annealing degree of carbon template (R). At R < 0.05, the material shows electrocatalytic properties in reactions of water splitting (η HER = -230 mV and η OER = 175 mV at j = 20 mA·cm −2 ). At 0.05 < R < 0.7, the practical application of the material lies in the field of chemical current sources and supercapacitors as a precursor ( C m = 20–200F·g −1 ). Materials with higher values of R (R > 0.7) do not exhibit either electrocatalytic or capacitive properties and are the subject of further research and search for practical use.