Improving the electrochemical performance of Li2MnO3 cathode material by micro-substitution of nickel to manganese

Nanostructured europium-doped layered lithium manganese oxide as a prospective cathode material for aqueous lithium-ion battery

“…The PXRD pattern of Li 2 Mn 0.95 Eu 0.05 O 3 is further characterized by noise, which is a well reported phenomenon and can be attributed to oxygen removal, defects during annealing or defects due to substitution [40]. Furthermore, the patterns exhibit the characteristic super lattice peaks at 20-25 • 2-theta angles corresponding to the Li/Mn ordering within the transition metal layers of the Li 2 MnO material indicating successful synthesis of the materials [42][43][44][45].…”

“…However, Li 2 Mn 0.95 Eu 0.05 O 3 shows a higher-level of particle size uniformity, shape uniformity and a decrease in the size of the secondary particles when compared to Li 2 MnO 3 . This has been observed in numerous reports [30,44,45,48] on doped cathode materials, and has been linked to improved porosity which could lead to enhanced performance of cathode materials due to increased surface area and shorter Li + diffusion pathways. EDX was used to determine the elemental composition of the synthesized nanostructured materials.…”

“…Furthermore, evidence of doping is observed by the slight movement of the (001) peak as shown in Fig. 2(b) to lower 2-theta angles [44]. The shift to lower angles also suggests that Eu-ions expanded the cell volume of the lattice due to partial replacement of Mn 4+ (0.67 Å) with Eu 3+ (10.87 Å) which may lead to broadening of Li-ion diffusion T. Mabokela et al pathways [44].…”

“…2(b) to lower 2-theta angles [44]. The shift to lower angles also suggests that Eu-ions expanded the cell volume of the lattice due to partial replacement of Mn 4+ (0.67 Å) with Eu 3+ (10.87 Å) which may lead to broadening of Li-ion diffusion T. Mabokela et al pathways [44]. By using PXRD data, the average crystallite size of both materials was calculated using the Scherrer Debye Eq.…”