X-ray Diffraction (XRD) and X-ray Absorption Near Edge Spectroscopy (XANES) Analyses of LiFe_1-xCu_xPO₄ Powders

Data analyses of XRD and XANES using Fe as absorber have been conducted which were aimed for phase identification, Fe oxidation state determination, absorption edge value (E₀ ) calculation, and valence electron determination of LiFe_xCu_1-xPO₄ (x = 3%, 4%, and 5%) powders. The powders were prepared by a dissolution method with the source of Fe was local ironstone from South Kalimantan, Indonesia. Analyses of the x-ray diffraction data of the powders were done using the Rietveld method. The XANES data were acquired using Fe K-edge spectral techniques at Synchrotron Light Research Institute (SLRI), Nakhon Ratchasima, Thailand. Results showed that olivine was the only identified phase in the LiFe_1-xCu_xPO₄ powders. Further analyses gave the crystallite size of 188, 193, and 205 nm and cell volume of 278.96, 279.12, and 280.52 A³, for the x = 3, 4, and 5% samples, respectively. Qualitative analysis of the XANES data acquired for all samples showed the oxidation state of Fe²⁺, and the absorption edge values (E₀ ) were 7121.56, 7121.71 and 7121.75 eV for the samples.