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Simplified search suggestions : Hafizah Rajaa Shaari

Synthesis of vanadium based lithium nickel aluminium oxide systems for good performance cathode materials of lithium-ion batteries

Hafizah Rajaa Shaari

Abstract

The objectives of this study is to synthesize lithium nickel oxide (LiNiO2) systems doped with vanadium (V) and aluminium (Al) which gives a constant and good discharge capacity for several cycles. Due to that, LiNi1-x-yAlyO2 systems were developed using carbon combustion synthesis (CCS) and solid-state reaction (SSR) method with different proportions ratio of V and Al which are x = 0.1 mole, and 0.3 mole and y = 0.1 mole. The sintering time used was 18 hours for SSR and five hours for CCS at 900°C. The first experiment is to obtain crystalline structure by x-ray diffraction analysis (XRD). The results revealed that the LiNi1-x-yVxAlyO2 are well defined hexagonal crystal system with Rd3m space group. The morphology characterization was done by using scanning electron microscopy (SEM). The SEM image for CCS samples show the presence of hexagonal structures for all the materials and it also was homogeneous. The SEM image of SSR samples showed that the particles distribution were irregul.....

Thesis Published 2018 1798 hits Available

Optical properties and emission cross-section of neodymium nanoparticles doped tellurite glass coated with graphene oxide/reduced graphene oxide

Hafizah Rajaa Shaari

Abstract

This study investigated the optical properties of neodymium nanoparticles (NPs) doped tellurite glass coated with graphene oxide (GO)/ reduced graphene oxide (rGO). Two series of glasses were prepared and coated using melt-quenching and spray-coating methods. The X-ray diffractograms proved the amorphous structure of the glass series. The presence of non-bridging oxygens in the glass network were proven via FTIR analysis. Meanwhile, the existence of neodymium nanoparticles in the tellurite glass network were confirmed using TEM analysis. FESEM and EDX analysis showed the morphologies of GO and rGO on the glass surface and their chemical elements, respectively. From UV-Vis spectroscopy analysis, the optical band gaps of ZBTNd (NPs)-GO and ZBTNd (NPs)-rGO were found in the range 2.355-2.998 eV and 2.770-3.125 eV, respectively. Meanwhile, the refractive index of ZBTNd (NPs)-GO and ZBTNd (NPs)-rGO were 2.041-2.194 and 2.339-2.657, respectively. Furthermore, the oxide ion polariz.....

Thesis Published 2024 737 hits Available

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