Communication
Rapid Synthesis of Citric Acid Coated Manganese Ferrite Nanoparticles: Electrochemical Supercapacitor Applications
Issue:
Volume 12, Issue 2, June 2024
Pages:
23-28
Received:
18 September 2024
Accepted:
11 October 2024
Published:
31 October 2024
Abstract: To manufacture nanoscale materials with high surface density, achieving average pore size and volume requires energy-intensive and time-consuming operations. We present a straightforward rapid, and quick approach for synthesizing citric acid coated manganese ferrite (MnFe2O4) nanoparticles through chemical co-precipitation with 1 M NaOH as an oxidative solution. The citric acid coated MnFe2O4 nanoparticles were studied by powder X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The powder X-ray diffraction results confirm the spinel structure of MnFe2O4 based on face centred cubic lattice parameters. The Fourier transform infrared spectroscopy results confirm the vibrational modes of citric acid coated MnFe2O4. The scanning electron microscope results of the as synthesised citric acid coated MnFe2O4 product had a spherical form with an average diameter of 20 nm. The electrochemical properties of MnFe2O4 nanoparticles were studied using cyclic voltammetry, charge-discharge, and electrochemical impedance spectroscopy using 1M NaOH as a electrolyte. Citric-acid coated MnFe2O4 nanoparticles shows pseudo-capacitance behaviour properties and delivers a specific capacitance value of about 381 F g-1 at 1 A g-1 specific current with 15% retention rate at high specific currents. The specific capacitance remained at 92% after 10,000 cycles at a specific current of 2 A g−1 which is clearly showed.
Abstract: To manufacture nanoscale materials with high surface density, achieving average pore size and volume requires energy-intensive and time-consuming operations. We present a straightforward rapid, and quick approach for synthesizing citric acid coated manganese ferrite (MnFe2O4) nanoparticles through chemical co-precipitation with 1 M NaOH as an oxida...
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Research Article
Heat and Mass Transfer on MHD Nanofluid Flow with Temperature-dependent Viscosity in the Presence of Chemical Reaction
Waheed Abdelwahab Ahmed,
Edward Richard Onyango*
,
David Theuri,
Faiz Awad
Issue:
Volume 12, Issue 2, June 2024
Pages:
29-44
Received:
18 November 2024
Accepted:
2 December 2024
Published:
23 December 2024
DOI:
10.11648/j.nano.20241202.12
Downloads:
Views:
Abstract: The paper investigated the effects of heat and mass transfer with the chemical reaction on time-dependent magnetohydrodynamic (MHD) free convection nanofluid flow through a vertical plate embedded in porous media. The flow problem is expressed as a set of time-dependent dimensional nonlinear partial differential equations, which are transformed into nonlinear partial differential equations (PDEs) in dimensionless form and then solved numerically using the bivariate spectral relaxation method (BI-SRM). The effect of the significant flow parameters such as Eckert number, Joule heating parameter, magnetic parameter, thermal Grashof number, mass Grashof number, Prandtl number, chemical reaction parameter, Schmidt number, and Reynolds number on both velocity components, temperature, concentration, and induction profiles is examined. Additionally, the effects of system parameters on heat and mass transport rates and primary and secondary shear stresses are investigated and shown in tabular and graphical form. It is established that by increasing the Schmidt number or chemical reaction parameter, the Sherwood number increases, while the reverse trend is seen on the concentration distribution for increasing either Schmidt number or chemical reaction parameter. The findings of the study play a significant role in enhancing the performance and proficiency of various engineering applications, such as new-generation washing machines and engineering applications found in the fields of oil refining and biomedical engineering.
Abstract: The paper investigated the effects of heat and mass transfer with the chemical reaction on time-dependent magnetohydrodynamic (MHD) free convection nanofluid flow through a vertical plate embedded in porous media. The flow problem is expressed as a set of time-dependent dimensional nonlinear partial differential equations, which are transformed int...
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