Development of Nanosized Mn3O4-Co3O4 on Multiwalled Carbon Nanotubes for Cathode Catalyst in Urea Fuel Cell

Abstract

Double-oxide Mn3O4-Co3O4 nanoparticles were synthesized and anchored on multiwalled carbon nanotubes (MWCNTs) via a single-step solvothermal method. The largest specific area (99.82 m2g−1) of the catalyst was confirmed via a nitrogen adsorption isotherm. Furthermore, the uniform coating of the Mn3O4-Co3O4 nanoparticles on the surface of the MWCNTs was observed via scanning electron microscopy and transmission electron microscopy; the uniform coating provided an effective transport pathway during the electrocatalytic activities. The rotating disk electrode and rotating ring disk electrode measurements indicated that the electron transfer number was 3.96 and the evolution of H2O2 was 2%. In addition, the Mn3O4-Co3O4/MWCNT catalyst did not undergo urea poisoning and remained stable in an alkaline solution. Conversely, commercial Pt/C could not withstand urea poisoning for long. The performance cell achieved a power density of 0.4226 mW cm−2 at 50 °C. Therefore, Mn3O4-Co3O4/MWCNT is an efficient and inexpensive noble-metal-free cathodic catalyst for direct urea fuel cells.

Engineering nanostructured Ag doped α-MnO2 electrocatalyst for highly efficient rechargeable zinc-air batteries

“…The stoichiometric ratio, morphologies, particle size, and crystallographic structures affect the catalytic activity of MnO 2 nanoparticles [ 21 , 22 ]. Hence, among the phases of MnO 2 nanoparticles α-MnO 2 shows the best catalytic activity as reported from previous works [ 23 ]. Different strategies such as preparing nanocomposites, doping with metal ions, tuning morphology, have been designed to improve intrinsic activity, catalytic activity and of MnO 2 nanoparticles [ 24 , 25 ].…”

Electrochemical Alcohol Oxidation and Biological Properties of Mn3O4-Co3O4-rGO

“…This XRD pattern is in full compliance with JCPDS 43-1003. 40 In this diffraction pattern, a peak of about 55°is also clear, which belongs to Mn 3 O 4 . The manganese oxide diffraction pattern is also in full compliance with JCPDS 27-0734.…”

“…The manganese oxide diffraction pattern is also in full compliance with JCPDS 27-0734. 40 In the XRD pattern of MCR, in addition to the characteristic peaks of MC, a wide peak of about 25 o is also seen, which belongs to rGO.…”

Enhanced Electrochemical Properties of Catalyst by Phosphorous Addition for Direct Urea Fuel Cell

“…The electrochemical and structural properties of the catalysts with and without P were compared. P addition improved the properties of the catalyst, facilitated uniform dispersion, and resulted in increased electrochemical activity (Pham and Yoon, 2020). The evenly dispersed catalyst exhibited a better catalytic activity toward the fuel and effectively oxidized urea in alkaline aqueous solutions.…”