Sr and Fe substituted LaCoO3 nano perovskites: Electrochemical energy storage and sensing applications

Perovskite-type LaCoO3 (LCO), La0.8Sr0.2CoO3 (LSCO), and La0.8Sr0.2Co0.9Fe0.1O3 (LSCFO) were prepared though a sol gel assisted hydrothermal method for supercapacitors and electrochemical sensors for heavy metal ions detection applications. Rhombohedral crystal structure was confirmed using experimental and DFT based computational XRD pattern. LCO, LSCO and LSCFO based modified carbon paste electrodes were prepared for cyclic voltammetry, electrochemical impedance spectra and galvanostatic charge discharge measurements. Among all electrodes, LSCFO results with 715.5 Fg(-1) specific capacitance with 97 % retention after 1500 cycles. Cyclic voltammetry measurements for the sensing and detection of heavy metal ions (chromium and mercury) were carried out using all three electrodes and observed that LSCFO showed better response comparatively to that of other two electrodes, thus can be claimed as a potential mixed metal oxide nanomaterial for the fabrication of electrodes for storage of energy and sensor applications.