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Article
Publication date: 5 May 2015

Jagdeep S. Sagu, Nicola York, Darren Southee and K.G.U. Wijayantha

The purpose of this paper is to report on the feasibility of the manufacture of printed rechargeable power sources incorporating, in the first instance, electrode structures from…

Abstract

Purpose

The purpose of this paper is to report on the feasibility of the manufacture of printed rechargeable power sources incorporating, in the first instance, electrode structures from the previous study, and moving on to improved electrode structures fabricated, via flexographic printing, using commercially available inks. It has been shown previously that offset lithography, a common printing technique, can be used to make electrodes for energy storage devices such as primary cells.

Design/methodology/approach

A pair of the original Ag/C electrodes, printed via offset lithography, were sandwiched together with a PVA-KOH gel electrolyte and then sealed. The resultant structures were characterised using electrochemical techniques and the performance as supercapacitors assessed. Following these studies, electrode structures of the same dimensions, consisting of two layers, a silver-based current collector covered with a high surface area carbon layer, were printed flexographically, using inks, on a melinex substrate. The characterisation and assessment of these structures, as supercapacitors, was determined.

Findings

It was found that the supercapacitors constructed using the offset lithographic electrodes exhibited a capacitance of 0.72 mF/cm2 and had an equivalent series resistance of 3.96 Ω. The structures fabricated via flexography exhibited a capacitance of 4 mF/cm2 and had an equivalent series resistance of 1.25 Ω The supercapacitor structures were subjected to bending and rolling tests to determine device performance under deformation and stress. It was found that supercapacitor performance was not significantly reduced by bending or rolling.

Originality/value

This paper provides insight into the use of printed silver/carbon electrodes within supercapacitor structures and compares the performance of devices fabricated using inks for offset lithographic printing presses and those made using commercially available inks for flexographic printing. The potential viability of such structures for low-end and cheap energy storage devices is demonstrated.

Details

Circuit World, vol. 41 no. 2
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 1 August 2023

Dhinesh S.K. and Senthil Kumar Kallippatti Lakshmanan

The purpose of this study is to increasing the gauge factor, reducing the hysteresis error and improving the stability over cyclic deformations of a conductive polylactic acid…

Abstract

Purpose

The purpose of this study is to increasing the gauge factor, reducing the hysteresis error and improving the stability over cyclic deformations of a conductive polylactic acid (CPLA)-based 3D-printed strain sensor by modifying the sensing element geometry.

Design/methodology/approach

Five different configurations, namely, linear, serpentine, square, triangular and trapezoidal, of CPLA sensing elements are printed on the thermoplastic polyurethane substrate material individually. The resistance change ratio of the printed sensors, when loaded to a predefined percentage of the maximum strain values over multiple cycles, is recorded. Finally, the thickness of substrate and CPLA and the included angle of the triangular strain sensor are evaluated for their influences on the sensitivity.

Findings

The triangular configuration yields the least hysteresis error with high accuracy over repeated loading conditions, because of its uniform stress distribution, whereas the conventional linear configuration produces the maximum sensitivity with low accuracy. The thickness of the substrate and sensing element has more influence over the included angle, in enhancing the sensitivity of the triangular configuration. The sensitivity of the triangular configuration exceeds the linear configuration when printed at ideal sensor dimensional values.

Research limitations/implications

The 3D printing parameters are kept constant for all the configurations; rather it can be varied for improving the performance of the sensor. Furthermore, the influences of stretching rate and nozzle temperature of the sensing material are not considered in this work.

Originality/value

The sensitivity and accuracy of CPLA-based strain sensor are evaluated for modification in its geometry, and the performance metrics are enhanced using the regression modelling.

Details

Rapid Prototyping Journal, vol. 29 no. 9
Type: Research Article
ISSN: 1355-2546

Keywords

Article
Publication date: 10 June 2022

Nur Atiqah Hamzah, Mohd Ann Amirul Zulffiqal Md Sahar, Aik Kwan Tan, Mohd Anas Ahmad, Muhammad Fadhirul Izwan Abdul Malik, Chin Chyi Loo, Wei Sea Chang and Sha Shiong Ng

This study aims to investigate the effects of indium composition on surface morphology and optical properties of indium gallium nitride on gallium nitride (InGaN/GaN…

Abstract

Purpose

This study aims to investigate the effects of indium composition on surface morphology and optical properties of indium gallium nitride on gallium nitride (InGaN/GaN) heterostructures.

Design/methodology/approach

The InGaN/GaN heterostructures were grown on flat sapphire substrates using a metal-organic chemical vapour deposition reactor with a trimethylindium flow rate of 368  sccm. The indium composition of the InGaN epilayers was controlled by applying different substrate temperatures. The surface morphology and topography were observed using field emission scanning electron microscope (F.E.I. Nova NanoSEM 450) and atomic force microscopy (Bruker Dimension Edge) with a scanning area of 10 µm × 10 µm, respectively. The compositional analysis was done by Energy Dispersive X-Ray Analysis. Finally, the ultraviolet-visible (UV-Vis) spectrophotometer (Agilent Technology Cary Series UV-Vis-near-infrared spectrometer) was measured from 200 nm to 1500 nm to investigate the optical properties of the samples.

Findings

The InGaN/GaN thin films have been successfully grown at three different substrate temperatures. The indium composition reduced as the temperature increased. At 760 C, the highest indium composition was obtained, 21.17%. This result was acquired from the simulation fitting of ω−2θ scan on (0002) plane using LEPTOS software by Bruker D8 Discover. The InGaN/GaN shows significantly different surface morphologies and topographies as the indium composition increases. The thickness of InGaN epilayers of the structure was ∼300 nm estimated from the field emission scanning electron microscopy. The energy bandgap of the InGaN was 2.54 eV – 2.79 eV measured by UV-Vis measurements.

Originality/value

It can be seen from this work that changes in substrate temperature can affect the indium composition. From all the results obtained, this work can be helpful towards efficiency improvement in solar cell applications.

Details

Microelectronics International, vol. 40 no. 1
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 17 October 2019

Iresha Herath, Ishanie Perera and Champika Hettiarachchi

Use of highly dye doped nano composite for organic pollutant degradation.

Abstract

Purpose

Use of highly dye doped nano composite for organic pollutant degradation.

Design/methodology/approach

One-pot synthesis of titanium nano-particles were carried out in the presence of N719 dye.

Findings

High dye doping and exceptional dye degradation efficiency was observed. Within 25 min, 99 per cent of methylene blue was removed from waste water.

Originality/value

A novel one-pot synthesis of the composite was introduced.

Details

Pigment & Resin Technology, vol. 49 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 29 June 2012

M. Amalina and M. Rusop

This research focuses on the effect of molar concentration of CuI thin film deposited by mist atomization technique. The result shows the CuI thin film properties strongly depends…

Abstract

This research focuses on the effect of molar concentration of CuI thin film deposited by mist atomization technique. The result shows the CuI thin film properties strongly depends on its precursor concentration. Thickness between 0.35 x 104 nm - 1.60 x 104 nm was obtained as the concentration increases. The increment of thickness affects the electrical properties which is the resistivity and conductivity of CuI thin film. The resistivity of about 101ω cm to 103ω cm was observed in those CuI thin films. For optical properties, the absorption coefficient and optical band gap of CuI was determined by using Tauc's plot. The high absorption coefficient of 106 m-1 is observed in those CuI thin films with bandgap between 2.84 to and 2.95eV obtained in this experiment.

Details

World Journal of Engineering, vol. 9 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

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