Bharathiar University

About: Bharathiar University is a education organization based out in Coimbatore, Tamil Nadu, India. It is known for research contribution in the topics: Thin film & Adsorption. The organization has 5812 authors who have published 8628 publications receiving 143934 citations. The organization is also known as: BU.

Synthesis and electrochemical performances of maricite-NaMPO4 (M = Ni, Co, Mn) electrodes for hybrid supercapacitors

Abstract: Sodium metal phosphates, NaMPO4 (M = Mn, Co and Ni) were successfully synthesized by a solution combustion synthesis (SCS) method using glycine-nitrate as a precursor. An XRD Rietveld refinement method revealed the crystal structure and lattice parameters of NaMPO4 (M = Mn, Co and Ni). For the first time, the crystal structure parameters of the orthorhombic NaNiPO4 maricite-type phase were evaluated. Similarly, it was identified that the NaCoPO4 and NaMnPO4 have high temperature hexagonal and maricite phases, respectively. The calculated BET specific surface areas (SBET) of NaMnPO4, NaCoPO4 and NaNiPO4 were 17.7, 22.6 and 18.7 m2 g−1, respectively. The NaMPO4 (M = Mn, Co and Ni) electrode exhibits good specific capacitance in 1 M NaOH electrolyte, when compared with 1 M Na2SO4, 1 M NaNO3 and 1 M NaCl. This difference in specific capacitance was analysed based on the influence of electrolyte anions (Cl−, SO42−, OH− and NO3−) and pH conditions of the electrolyte solution. Overall, maricite-NaNiPO4 nanoparticles provided a high specific capacitance of 368 F g−1 compared to NaMnPO4 (163 F g−1) and NaCoPO4 (249 F g−1) in 1 M NaOH electrolyte. Subsequently, a hybrid supercapacitor (AC‖NaNiPO4) was fabricated and it delivered a good specific capacitance and cyclic stability compared to the commercially available device.

Electrochemical properties of microwave-assisted reflux-synthesized Mn3O4 nanoparticles in different electrolytes for supercapacitor applications

Abstract: The nanosized Mn3O4 particles were prepared by microwave-assisted reflux synthesis method The prepared sample was characterized using various techniques such as X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FT-IR), Raman analysis, and transmission electron microscopy (TEM) Electrochemical properties of Mn3O4 nanoparticles were investigated using cyclic voltammogram (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge–discharge analysis in different electrolytes such as 1 M KCl, 1 M Na2SO4, 1 M NaNO3, and 6 M KOH electrolytes XRD pattern reveals the formation of single-phase Mn3O4 nanoparticles The FT-IR and Raman analysis also assert the formation of Mn3O4 nanoparticles The TEM image shows the spherical shape particles with less than 50 nm sizes Among all the electrolytes, the Mn3O4 nanoparticles possess maximum specific capacitance of 94 F g−1 in 6 M KOH electrolyte calculated from CV The order of capacitance obtained by various electrolytes is 6 M KOH > 1 M KCl > 1 M NaNO3 > 1 M Na2SO4 The EIS and galvanostatic charge–discharge results further substantiate with the CV results The cycling stability of Mn3O4 electrode reveals that the prepared Mn3O4 nanoparticles are a suitable electrode material for supercapacitor application