Following several years as chairman of the Design Matters Group at the UK Royal Academy of Engineering, James Armstrong prepared at the request of the Academy a booklet outlining the basic strategic principles of engineering design, illustrated by four case studies. James Armstrong has a wide range of experience relating to many different projects and requiring the integrating of many diff…
To write a second edition of a textbook is a very challenging enterprise for the author in many aspects. First of all it gives the chance to back up the content and the text from the previous edition with all the experience he has collected after the first edition was distributed and to include the full set of advices and recommendations he had received from colleagues and students. As impo…
To write a second edition of a textbook is a very challenging enterprise for the author in many aspects. First of all it gives the chance to back up the content and the text from the previous edition with all the experience he has collected after the first edition was distributed and to include the full set of advices and recommendations he had received from colleagues and students. As impo…
Since the appearance of our book, Fundamentals of Semiconductors: Physics and Materials Properties, one of the questions we are asked most frequently is this: “is there a solution manual to this book?” In preparing the questions at the end of each chapter we have already tried to guide the readers to derive the answers by themselves using a step-by-step approach. Clearly this strategy …
The physics of narrow gap semiconductors is an important branch of semiconductor science. Research into this branch focuses on a specific class of semiconductor materials which have narrow forbidden band gaps. Past studies on this specific class of semiconductor materials have revealed not only general physical principles applicable to all semiconductors, but also those unique characteristics o…
The aim of this book is to provide a practical guide on the fundamentals, status of present technology and applications of excimer lasers. Theoretical details have been intentionally omitted. The book has emerged from “Excimer laser technology: Laser sources, optics, systems and applications” issued earlier by a manufacturer of excimer lasers. The scope of the book has been considerably enl…
The aim of this book is to provide a practical guide on the fundamentals, status of present technology and applications of excimer lasers. Theoretical details have been intentionally omitted. The book has emerged from “Excimer laser technology: Laser sources, optics, systems and applications” issued earlier by a manufacturer of excimer lasers. The scope of the book has been considerably enl…
The study of environmental physics requires understanding topics from many different areas of physics as well as comprehension of physical aspects of the world around us. Several excellent textbooks are available covering most aspects of environmental physics and of applications of physics to the natural environment from various points of view. However, while teaching environmental physics to u…
Abstract. As the application of fibre-reinforced polymer composite material continue to increase day by day, so the knowledge about the impact behaviour of fibre-reinforced polymer composite structures in the areas such as automotive and aerospace is very much needed. This article attempts a comprehensive review of recent literature in the broader area of impact damage. Testing methods and sta…
Abstract. BaTiO3 is a typical ferroelectric material with high relative permittivity and has been used for various applications, such as multilayer ceramic capacitors (MLCCs). With the tendency of miniaturization of MLCCs, the thin films of BaTiO3 have been required. In this work, BaTiO3 thin films have been deposited on Pt-coated Si substrates by RF magnetron sputtering under different deposi…
Abstract. Metal–insulator–metal (MIM) capacitors with excellent electrical properties have been fabricated using high-κ TaAlOx-based dielectrics. TaAlOx films having thickness of 11.5–26.0 nm, with equivalent oxide thickness (EOT) of ~2.3–5.3 nm were deposited on top of Au/SiO2 (180 nm)/Si (100) structures by radio frequency magnetron co-sputtering of Ta2O5 and Al2O3 targets. The s…
Abstract. The microstructure and chemistry of the high-k gate dielectric significantly influences the performance of metal–insulator–metal (MIM) and metal–oxide–semiconductor devices. In particular, the local structure, chemistry, and inter-layer mixing are important phenomena to be understood. In the present study, high resolution and analytical transmission electron microscopy are…
In this work, we studied a TiO2 mixed LaAlO3 dielectric (TLAO) for metal–insulator–metal (MIM) capacitors. The resulting capacitor characteristics showed a high capacitance density of 23.2 fF/μm2 and a low leakage current of 7.5 10-7 A/cm2 at 1 V. Comparing to the control samples of TiLaO (TLO), TLAO dielectrics with Al2O3 doping showed lower leakage current, smaller voltage nonline…
Abstract. MIS capacitors with 16-nm high-k dielectric HfO2 and 50–150 nm TaN electrode were studied after postmetal- annealing (PMA) at various conditions. The effect of TaN thickness on electrical and physical properties is summarized. It has been found that the thermal stability of the TaN/HfO2 depends on TaN thickness. A reduction of leakage current and an increase of breakdown voltage…
Abstract We have deposited Pb0.92La0.08Zr0.52Ti0.48O3 (PLZT) films on nickel and copper substrates to create film-on-foil capacitors that exhibit excellent dielectric properties and superior breakdown strength. Measurements with PLZT films on LaNiO3-buffered Ni foils yielded the following: relative permittivity of 1300 (at 25 ◦C) and 1800 (at 150 ◦C), leakage current density of 6.6×10−9…
Abstract. Lithiated spinel, LiCrTiO4 is synthesized by sonochemical method followed by calcination at 923 K for 2 h. The prepared material is characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersion X-ray spectroscopy (EDX). Cubic phase LiCrTiO4 with Fd3m space group is evident from the XRD. Particles o…
Abstract. Nano-size (≤100 nm) TiP2O7 is prepared by the urea assisted combustion synthesis, at 450 and 900 ◦C. The compound is characterized by powder X-ray diffraction, Rietveld refinement, high resolution transmission electron microscopy and surface area methods. Lithium cycling properties by way of galvanostatic cycling and cyclic voltammetry (CV) showed a reversible and stable capac…
Abstract. A facile soft templating strategy has been developed for synthesizing hollow spheres of nanocarbon by hydrothermal process. In this soft templating strategy, poly (ethylene oxide)epoly (propylene oxide) epoly (ethylene oxide) block co-polymers are used as the template while α-cyclodextrin are employed as the carbon precursor. After hydrothermal treatment, the soft templates can b…
Abstract. A hybrid asymmetric electrochemical supercapacitor is constructed by employing two different nanostructured conducting polymers of polypyrrole (PPy) and self-doped polyaniline (SDPA). Different electrochemical methods, including cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy (EIS), are performed to characterize the electrochemical per…
Abstract. Nanostructured self-doped polyaniline (SDPA) is prepared from an aqueous solution of aniline and maminobenzoic acid using an electrochemical method onto a stainless steel electrode. This electrode employed as a positive shared electrode in the construction of a hybrid battery–supercapacitor energy storage system AC/SDPA/Zn. This hybrid system is constructed using a parallel combi…
Abstract. Chemical modification of graphene nanosheets by KOH was examined as a way to enhance the specific capacity of graphene nanosheets in supercapacitor. Fourier transform infrared spectroscopy, Raman spectroscopy and X-ray photoelectron spectroscopy were used to investigate the effects of the treatment on the surface of the graphene nanosheets. The specific capacitance of 136 F g−1 …
Abstract. Nitrogen-doped graphene has been a recent research focus. It is crucial to further utilize the excellent properties of graphene macroscopic assemblies. Herein, we first report a unique and convenient hydrothermal process for controlled synthesis and structural adjustment of the nitrogen-doped graphene hydrogel (GN-GH), which can be readily scaled-up for mass production of nitroge…
Abstract. Nitrogen-doped graphene sheets (NGS) were obtained using a simple hydrothermal reaction with graphene oxide and hexamethylenetetramine (HMT). HMT plays important roles in both reducing graphene oxide and doping nitrogen into the graphene sheets. The prepared nitrogen-doped graphene sheets reduced by hexamethylenetetramine (NGS-HMT) have a high nitrogen (8.62 atom%) content, in wh…
Abstract. Three kinds of reduced graphene oxides are prepared by hydrothermal reduction under different pH conditions and their pseudocapacitive performances are evaluated using full-cell supercapacitor devices. The pH values are found to have great influence on the performance of the supercapacitors, achieving the highest specific capacitance value reported for hydrothermal reduced graphen…
Abstract. A series of cobalt oxide/graphene nanocomposites have been successfully synthesized by adding carbon blacks filler. We have introduced carbon blacks to act as a structural modifier in fabricating graphene based composites. The composites were prepared by ultrasonication and microwave-assisted methods. Microstructure measurements showed that carbon blacks could be conductive links …
Abstract. 20 nm sized Co3O4 nanoparticles are in-situ grown on the chemically reduced graphene oxide (rGO) sheets to form a rGO-Co3O4 composite during hydrothermal processing. The rGO-Co3O4 composite is employed as the pseudocapacitor electrode in the 2 M KOH aqueous electrolyte solution. The rGOeCo3O4 composite electrode exhibits a specific capacitance of 472 F g-1 at a scan rate of 2mV s…
ABSTRACT This paper reports the results of electrical characterization of aluminum thin films. Uniform Al thin films were deposited by physical vapor deposition (PVD) technique on glass substrates. The electrical resistivity of the films as a function of film thickness was studied. These parameters have been measured by four-point probe method. The electrical resistivity was obtained by the me…
Abstract A comparison of the volume conductivity measured by standard four-electrode (FE) and four-point probe (FPP) methods for graphite-based powdery polypropylene (PP) and poly(vinylidene fluoride) (PVDF) composite bar specimens was made in this study. Significant difference in the conductivity data obtained by standard FE and FPP methods was found for highly conductive PP and PVDF composi…
Abstract Four-point probe characterization is a standard method for studying the electrical properties of solids and thin films. The probe spacing in four-point probe technique has to be reduced to micro-scale to obtain expected surface sensitivity and spatial resolution. Therefore, microscopic four-point probes (M4PPs) need to be combined with some microscopy techniques. Two types of M4PPs sy…
Abstract. Multi-walled carbon nanotube (MWCNT)/MnO2 supercapacitor electrodes containing MnO2 nanoflakes in the MWCNT network are fabricated through the oxidation of manganese acetate with poly(4- styrenesulfonic acid) (PSS) dispersed MWCNTs. The structural evolution of the electrodes under charge/discharge (reduction/oxidation) cycles and its impact on the electrodes’ electrochemical pro…
Abstract. Effect of stacking structure of single-walled carbon nanotubes (SWCNTs) on its performance as electrode of supercapacitor was investigated in the present work. Considering SWCNTs easily formed bundles due to strong van de Waals attraction between tubes, we proposed first dispersion of SWCNTs by ionic liquids (ILs) of 1-ethyl-3-methyl imidazolium tetrafluoroborate (EMIMBF4), follow…
Abstract. A method of in situ integrating carbon nanotubes (CNTs) into activated carbon (AC) matrix was developed to improve the performance of AC as a supercapacitor electrode. Glucose solution containing pre-dispersed CNTs was hydrothermally carbonized to be a char-like intermediate product, and finally converted into a “tube-in-AC” structure by the chemical activation using KOH. The …
Abstract. The capacitive deionization (CDI) technology using different activated carbon electrodes was investigated to desalinate. The effect of specific surface area and pore structure of the activated carbon electrodes on the amount of ions removed in CDI was demonstrated. A highly mesoporous activated carbon (ACk2) was chosen to study desalination performance in detail. It is found that …
Synopsis The principles of microwave heating are discussed with reference to dielectric properties, heating phenomena and microwave equipment. Microwave regeneration of granular activated carbon for the carbon-in-pulp process is examined on a laboratory scale, with special attention being given to highlight the problem areas and specific considerations related to microwave heating. Results ind…