Annealing effect on structural and electrochemical performance of Ti-doped LiNi1/3Mn1/3Co1/3O2 cathode materials

NMC 111 cathode materials exhibit engaging properties in high energy density and low cost, making it great potential for the next generation of high-energy lithium-ion batteries. However, it still faces challenges such as fast capacity fade, especially at high C rates. Herein, we implement the novel Ti-doped cathode material, LiNi0.3Mn0.3Co0.3Ti0.1O2 (NMCT) synthesized via the combustion method. It was discovered that NMCT can effectively improve capacity delivery at high C rates. The T80 material demonstrated superior electrochemical annealed at 800 ˚C for 72 h, with an exceptional specific discharge capacity of 148.6 mAh g-1 and excellent cycle stability (capacity retention 96.8 %) after 30th cycles at 3 C. The results demonstrated that Ti-doped NMC had superior advantages for LiNi1/3Mn1/3Co1/3O2 (NMC 111) material at the optimum temperature of 800 °C for 72 h. It is one of the potential cathode materials for Li-ion batteries

Investigation of bandgap energies of a single phase Zn(₁₋ₓ)CuₓO nanoparticles / Suraya Ahmad Kamil … [et al.]

ZnO nanostructures are extensively studied due to their attractive characteristics and behaviour with wide band gap (3.4 eV) and large exciton binding energy (60 meV) Recently, there have been a lot of interests in studying modified ZnO nanostructures. The prospect of magnetically controlled operation of semiconductor devices has provoked intensive research to develop transition metal doped wide-band-gap semiconductors,i.e. diluted magnetic semiconductors (DMS) with room temperature ferromagnetism. Among transition metals, Cu is an especially interesting dopant because that Cu-related compounds are not strongly ferromagnetic. Transition metal-doped ZnO offers the potential for realizing room temperature operation of active spintronic devices as well as rich and fascinating fundamental physics

Effects of the Absorption Behaviour of ZnO Nanoparticles on Cytotoxicity Measurements

ZnO absorbs certain wavelengths of light and this behavior is more pronounced for nanoparticles of ZnO. As many toxicity measurements rely on measuring light transmission in cell lines, it is essential to determine how far this light absorption influences experimental toxicity measurements. The main objective was to study the ZnO absorption and how this influenced the cytotoxicity measurements. The cytotoxicity of differently sized ZnO nanoparticles in normal and cancer cell lines derived from lung tissue (Hs888Lu), neuron-phenotypic cells (SH-SY5Y), neuroblastoma (SH-SY5Y), human histiocytic lymphoma (U937), and lung cancer (A549) was investigated. Our results demonstrate that the presence of ZnO affected the cytotoxicity measurements due to the absorption characteristic of ZnO nanoparticles. The data revealed that the ZnO nanoparticles with an average particle size of around 85.7 nm and 190 nm showed cytotoxicity towards U937, SH-SY5Y, differentiated SH-SY5Y, and Hs888Lu cell lines. No effect on the A549 cells was observed. It was also found that the cytotoxicity of ZnO was particle size, concentration, and time dependent. These studies are the first to quantify the influence of ZnO nanoparticles on cytotoxicity assays. Corrections for absorption effects were carried out which gave an accurate estimation of the concentrations that produce the cytotoxic effects

Catalytic gasification of oil palm frond biomass in supercritical water using MgO supported Ni, Cu and Zn oxides as catalysts for hydrogen production

Non-noble metal supported catalysts such as 20NiO/MgO, 20CuO/MgO and 20ZnO/MgO were catalyzed the gasification of oil palm frond biomass in supercritical water for hydrogen production. All the catalysts are found to be pure with no impurities present. The specific surface area of these catalysts can be arranged in the order of 20NiO/MgO (30.1 m2 g–1) > 20CuO/MgO (16.8 m2 g–1) > 20ZnO/MgO (13.1 m2 g–1). Although catalysts with larger specific surface area are beneficial for catalytic reactions, in this study, the largest specific surface area did not lead to the highest catalytic performance. It is found that the 20ZnO/MgO catalyst (118.1 mmol ml−1) shown the highest H2 yield than the 20CuO/MgO (81.1 mmol ml−1) and 20NiO/MgO (72.7 mmol ml−1) catalysts. In addition, these supported catalysts also shown higher H2 selectivity with reached 83.8%, 84.9% and 87.6% for 20CuO/MgO, 20NiO/MgO and 20ZnO/MgO catalysts. Other factors such as dispersion, basicity and bond strength play more important roles in supercritical water gasification of biomass to produce hydrogen

Catalytic supercritical water gasification of oil palm frond biomass using nanosized MgO doped Zn catalysts

In this work, nanosized MgO doped Zn catalysts (Mg1-x Znx O; x = 0.05, 0.10, 0.15, 0.20) were catalyzed the supercritical water gasification (SCWG) of oil palm frond (OPF) biomass for hydrogen production. Increased the amount of Zn in the catalyst enlarged the crystallite size, thus, reduced the surface area. Interestingly, all the synthesized catalysts have crystallite sizes of less than 50 nm. In-depth Rietveld refinement analysis revealed that the enlargement of the crystallite size is due to the phenomenon of cell expansion when the smaller Mg2+ ions being replaced by the larger Zn2+ ions during the doping process. Increased the Zn content also improved the basicity properties. Among the synthesized catalysts, the Mg0.80 Zn0.20 O exhibited the highest total gas volume of 213.5 ml g-1 of the biomass with 438.1% of increment in terms of H2 yield. The metal oxide doped materials serve as a new catalyst structure system for the SCWG technology

Stoichiometry and Materials Science - When Numbers Matter

The aim of this book is to provide an overview on the importance of stoichiometry in the materials science field. It presents a collection of selected research articles and reviews providing up-to-date information related to stoichiometry at various levels. Being materials science an interdisciplinary area, the book has been divided in multiple sections, each for a specific field of applications. The first two sections introduce the role of stoichiometry in nanotechnology and defect chemistry, providing examples of state-of-the-art technologies. Section three and four are focused on intermetallic compounds and metal oxides. Section five describes the importance of stoichiometry in electrochemical applications. In section six new strategies for solid phase synthesis are reported, while a cross sectional approach to the influence of stoichiometry in energy production is the topic of the last section. Though specifically addressed to readers with a background in physical science, I believe this book will be of interest to researchers working in materials science, engineering and technology

Synthesis and characterization of Ti-doped MgMn2O4 cathode material for magnesium ion batteries

Magnesium batteries demonstrate potential candidate for next-generation energy storage devices because of their high energy density and low raw-materials costs. In comparison with lithium, magnesium is inherently much safer due to its air stable and environmental friendly. In the present work, magnesium manganese oxide (MgMn 2 O 4 ) with Ti-doped was synthesized by a self-propagating combustion method using citric acid as a reducing agent. The precursors of MgMn 2 O 4 and MgMn (2-x) Ti x O 4 , (x = 0.1) were annealed at 700 °C for 24 h. The prepared samples were further characterized by using Simultaneous Thermal Analysis (STA), X-ray diffraction (XRD), and Field Emission Scanning Electron Microscopy (FESEM). Then, the optimized sample was used as cathode in magnesium ion battery using polymer-based electrolyte. The charge-discharge profile of the fabricated battery was discussed