Investigation on the electrochemical performance of hausmannite Mn3O4 nanoparticles by ultrasonic irradiation assisted co-precipitation method for supercapacitor electrodes

• Published in: Journal of Taibah University for Science Vol. 12; no. 5; pp. 669 - 677
• Main Authors: Tholkappiyan, R., Naveen, A. Nirmalesh, Vishista, K., Hamed, Fathalla
• Format: Journal Article
• Language: English
• Published: Taylor & Francis 01.01.2018; Taylor & Francis Group
• Subjects: electrochemical performance; electrode; Mn3O4 nanoparticles; nanoparticles; oxidation state; Spinel
• ISSN: 1658-3655
• DOI: 10.1080/16583655.2018.1497440

Spinel type manganese oxide (Mn 3 O 4 ) nanoparticles were synthesized by ultrasonic irradiation assisted co-precipitation method using PEG and NaOH. The formation of tetragonal hausmannite phase (Mn 3 O 4 ) with spinel structure was confirmed from XRD and FTIR studies. The average crystallite size of Mn 3 O 4 nanoparticles was determined from Scherrer formula (39.9 nm) and Williamson-Hall relation (36.5 nm). The presence of elements, the overall oxidation state of manganese (Mn 2+ , Mn 3+ and Mn 4+ ) and chemical composition of these nanoparticles were determined from Mn 2p, Mn 3s and O 1s spectra using XPS. The spherically shaped morphology of these nanoparticles was analysed by SEM. The expected chemical composition of Mn 3 O 4 nanoparticles was analysed by EDS. The electrochemical performance of these Mn 3 O 4 nanoparticles was studied by CV, CP and AC impedance analysis. The maximum specific capacitance of Mn 3 O 4 nanoparticles was found to be 296 F/g at a current density of 1 A/g 2 . Nyquist plot shows lower value of resistance that indicates the good electrical conductivity of the Mn 3 O 4 electrode, which accounts for the improved electrochemical performance of the supercapacitors. Hence, the use of surfactant and the presence of ultrasonic irradiation in the synthesis process plays a dominant role in the electrochemical performance of Mn 3 O 4 supercapacitors.