Publications by authors named "V M Maphiri"

In this work, trivalent Yttrium doped calcium aluminate (CaAlO:x% Y) were synthesized for the first time. Through Photoluminescence (PL) spectroscopy and Commission Internationale de l'Eclairage (CIE), CaAlO:0.1 % Y has demonstrated to be a potential high emitting phosphor material amongst other high concentration Y doped samples, emitting a vibrant blue - pink hue where others are emitting a transiting hue from blue to green within a white vertex region.

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In this work, a thermally reduced graphene oxide (TRGO) thin film on microscopic glass was prepared using spray coating and atmospheric pressure chemical vapour deposition. The structure of TRGO was analysed using X-ray diffraction (XRD) spectroscopy, scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), Fourier transform infrared (FTIR) spectroscopy, and ultraviolet-visible spectroscopy (UV-Vis) suggesting a decrease in oxygen functional groups (OFGs), leading to the restacking, change in colour, and transparency of the graphene sheets. Raman spectrum deconvolution detailed the film's parameters, such as the crystallite size, degree of defect, degree of amorphousness, and type of defect.

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We demonstrate a simple method to fabricate all solid state, thermally reduced graphene oxide (TRGO) microsupercapacitors (µ-SCs) prepared using the atmospheric pressure chemical vapor deposition (APCVD) and a mask-free axiDraw sketching apparatus. The Fourier transform infrared spectroscopy (FTIR) shows the extermination of oxygen functional groups as the reducing temperature (RT) increases, while the Raman shows the presence of the defect and graphitic peaks. The electrochemical performance of the µ-SCs showed cyclic voltammetry (CV) potential window of 0-0.

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