Improved electrochemical performance of rare earth doped Bi1−xMxPO4 (x = 0, 0.15; M = La, Ce, Sm) Nanostructures as electrode material for energy storage applications

Bismuth phosphate is one of the emerging electrode materials for various energy storage applications. Here we analyzed the electrochemical behavior of doped bismuth phosphate nanostructures with La, Ce, and Sm synthesized using a hydrothermal route. The electrochemical performance of these rare earth-doped bismuth phosphate nanostructures has never been reported earlier. The structural and morphological analysis confirms the hexagonal and monoclinic phases. High–resolution X-ray photoelectron spectroscopy (XPS) spectra confirm the oxidation states of the synthesized samples. Various doping elements play a significant role in tuning the electrochemical property of working electrodes for super cappetry/energy storage applications. All the pure and doped working electrodes exhibited the high potential window of 1.4 V in an aqueous electrolyte which is an important parameter to enhance the energy density for the device applications. The specific capacity is found to be maximum for Sm-doped bismuth phosphate nanostructures, i.e., 1135 Cg ⁻¹at the current density of 1 Ag ⁻¹. The cycle stability test was performed for the Sm-doped bismuth phosphate sample for 4000 cycles with 92 % retention. The results analysis revealed that Sm doped bismuth phosphate nanostructures as a electrode material has great potential for practical utility in energy storage applications.