Sc-based coordination polymer with concaved superstructures: preparation, formation mechanism, conversion and their electrochemistry properties
In this work, metastable Sc-based coordination polymer (ScCP) octahedrons with diameter of about 5 μm have been fabricated by a facile solvothermal method. The ScCP octahedrons are constructed by numerous nanoparticles with size of 10-20 nm via a self-assembly process. Interestingly, ScCP octahedrons with concaved surfaces, which is seldom reported in literature owing to the major challenge of high surface energy and not favored by thermodynamics. The influence of the reaction temperature, reaction time and molar ratio of reagent on the sizes and morphologies of the as-prepared products was systematically investigated, and the possible formation mechanism of the concaved ScCP octahedron was proposed. At lower temperature, ScCP octahedron grows via a conventional Ostwald ripening route. While a mesoscopic self-assembly process is suggested at higher temperature. Sc2O3/C octahedrons were obtained after the simple calcination in N2 atmosphere, further the electrochemical properties were studied. It is believed this facile synthesis may give guidance for the preparation of CPs with complex morphologies.