CONICET | Buscador de Institutos y Recursos Humanos

Cobalt-based perovskite exhibit fascinating physical properties at the nanoscale. Better oxygen transport, higher ionic/electronic mixed conductivity and enhanced electrocatalytic activity are some of the most important highlighted properties compared to bulk perovskites. Such materials have proved to be excellent candidates for applications in solid oxide fuel cells and supercapacitors. In this work, a technological approach using highly ordered porous anodic aluminum oxide (AAO) as a template for the synthesis of low dimensional SrCo0.95V0.05O3 cubic perovskite is introduced. Thus, the impregnation of AAO membranes in two different mixed oxide precursor solutions, citric acid, on the one hand, and tartaric acid on the another hand, followed by thermal treatments and alumina dissolution, led to the successful synthesis of alumina-embedded SrCo0.95V0.05O3 nanostructured perovskite. By means of the Rietveld method refinement of the XRD data, the perovskite crystallization in a Pm-3m cubic system, as well as some crystalline phases of alumina were identified. FT-IR results showed the presence of a band at ~580 cm−1 for the nanostructured perovskites, attributed to the asymmetric stretching of the (Co/V)?O bonds, in good agreement with those exhibited by bulk perovskites. In addition, the capacitive behavior of composite electrodes prepared with low dimensional perovskites and lubricating graphite was monitored by cyclic voltammetry and galvanostatic charge/discharge cycles. Our results show an improved supercapacitive performance of the nanostructured perovskite respect to that obtained for the bulk configuration, indicating that nanostructured SrCo0.95V0.05O3 perovskite arises as a promising candidate material for supercapacitor devices.

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