Electrochemical exploration of perovskite structured LaCoO3 nanoparticles embedded on MXene sheets for high-performance energy conversion and storage devices

The growth of heterostructures nanomaterials with abundant active sites and outstanding electrical conductivity are essential to boost the electrochemical performance of energy storage and energy conversion applications. In this report, LaCoO₃ and LaCoO₃/MXene nanocomposite (NCs) are prepared by the simple hydrothermal route and prepared samples were analyzed for structural, morphological, and elemental composition using powder X-ray diffraction, SEM, EDX with mapping, HRTEM, FTIR and XPS techniques. The essential electrochemical properties of the prepared NCs were analyzed by CV, GCD, LSV and EIS studies. The specific capacitances (Csp) of perovskite LaCoO₃/MXene NCs have achieved 1253.27 F/g at 5 mV/s. The prepared LaCoO₃/MXene NCs revealed outstanding capacitance retaining up to 87.5 % after 5000 cycles. The LaCoO₃/MXene||MXene was used as asymmetric supercapacitor (ASC) device, which is delivered notable energy density (ED) of 159.28 Wh/kg and a power density (PD) of 1440 W/kg at 1 A/g. After 5000 continuous cycles, the fabricated ACS device capacitance retains of 90.95 % and exhibits a coulombic efficiency of 95.8 %. In addition, from the oxygen evaluation reaction (OER) analysis the LaCoO₃/MXene NCs exhibits overpotential of 321 mV corresponding to the 10 mA/cm² current density, along with the lesser Tafel slope 77.09 mV/dec for OER in 1 M KOH. As a result, the prepared LaCoO₃/MXene electrode having exceptional qualities might prove toward the trustable electrode material for the front-line supercapacitors and water splitting applications.