SYNTHESIS, CHARACTERIZATION AND OPTICAL BAND GAP OF LITHIUM CATHODE MATERIALS: LI2NI8O10 AND LIMN2O4 NANOPARTICLES

Abstract

ABS TRACT: Li 2 Ni 8 O 10 and LiMn 2 O 4 Nanoparticles as cathode materials for lithium ion battery were successfully synthesized using lithium acetate, nickel and manganese acetate as Li, Ni and Mn sources and stearic acid as a complexing reagent. The structure of the obtained products was characterized by FT-IR and XRD. The shape, size and distribution of the Li 2 Ni 8 O 10 and LiMn 2 O 4 nanoparticles were observed by SEM. Optical band gap and magnetic properties were determined by diffuse reflectance spectroscopy (DRS) and vibrating sample magnetometer (VSM). Li 2 Ni 8 O 10 and LiMn 2 O 4 spinels were identified as the main crystalline phases. The particles size of both, Li 2 Ni 8 O 10 and LiMn 2 O 4 nanoparticles is around 24 to 32 nm. Optical band gap of Li 2 Ni 8 O 10 and LiMn 2 O 4 are 1.40 eV and 1.16 eV, respectively. Therefore, lithium nickel and lithium manganese oxide nanoparticles can be used as semiconductor materials in electrical devices. VSM curve showed paramagnetic behavior of LiMn 2 O 4 nanoparticles. Moreover, color parameters were obtained by colorimetric analysis of LiMn 2 O 4 indicating characteristic values of L*=25.820, a*=1.607 and b*= -1.143.