摘要
The present work aimed to investigate the electrochemical properties of ITO substrates in propylene carbonate(PC) with 0.5 mol/L lithium perchlorate(LiClO_(4)) medium in the presence of elaborated thin films of cerium dioxide pure and doped with manganese at varying percentages.Ce_(1-x)Mn_(x)O_(2)(x=0 wt%,2 wt%,4 wt% and 6 wt%) were successfully deposited by the spray pyrolysis(SP) technique on the glass substrate and ITO at 450℃.The effects of manganese(Mn) doped thin films Ce_(1-x)Mn_(x)O_(2) were studied and investigated by using different analyses namely X-ray diffraction(XRD) analysis,Raman spectroscopy method,UV-Vis spectrophotometer technique,atomic force microscopy(AFM) analysis and electrochemical properties.XRD data obtained present a polycrystalline with a face-centred cubic structure of fluorite type.Raman results of undoped and Mn doped thin films show two peaks at 465 and 600 cm^(-1),due to the formation of extrinsic oxygen vacancies by the incorporation of Mn into Ce1-xMnxO_(2) matrix.Energy dispersive spectroscopy(EDS) data show the presence of Ce,O,and Mn elements in the elaborated films.The AFM results reveal that the surface roughness decreases with increasing Mn rate.Further,band gap energy of thin films decreases with increasing in Mn rate due to the formation of defect state between valence and conduction band.The storage capacity of the elaborated Ce_(1-x)Mn_(x)O_(2)/ITO/PC+LiClO_(4) electrode reaches a maximum of 1.997 mF in the presence of 6 wt% of Mn.
基金
Project supported by Moroccan Ministry of Higher Education and Research and CNRST,Morocco in the framework of ERANETMED-NIn FFE,PPR/37/2015 and PPR/9/2015 projects。
