Cost effective urea combustion derived mesoporous-Li2MnSiO4 as a novel material for supercapacitors

Mesoporous-Li2MnSiO4 (LMS) having a surface area of 35 (+/-2) m(2) g(-1) is produced using a very simple, fast and cost effective urea combustion method for the first time and characterized by X-ray diffraction, fieldemission scanning electron microscopy, transmission electron microscopy and surface area analysis. Li2MnSiO4 is crystallized in the orthorhombic phase with space group - Pmn2(1). The lattice parameters: a = 6.317(10) angstrom, b = 5.385(9) angstrom, c = 4.988(8) angstrom are calculated by the Rietveld method. The urea combustion derived LMS is found to be thermally stable till 600 degrees C in air and thereafter disintegrates into Li2SiO3 (orthorhombic) and MnO2 (cubic). The presence of a homogeneous mesoporous (<20 nm) framework with a high surface area shows orthorhombic Li2MnSiO4 to be promising as a novel supercapacitor electrode as it delivers a specific capacitance of 175 (+/-5) F g (1) at 3 mV s (1) in 2 M KOH solution. The supercapacitive performance was further examined by galvanostatic charge-discharge cycling and complimented by electrochemical impedance spectroscopy.