Self-Powered LED System Using Carbon-Based Nanofluid Photothermoelectric Storage
Led by Ts. Dr. Megat Muhammad Ikhsan Bin Megat Hasnan.
Ts. Dr. Megat Muhammad Ikhsan Bin Megat Hasnan joined the Faculty of Engineering at Universiti Malaysia Sabah under the Electric and Electronic Programme as a senior lecturer on November 20, 2021, until the present. He received a degree, a master's degree, and a Ph.D. from the University of Malaya, Kuala Lumpur, Malaysia. Currently, Dr. Megat is actively pursue his research activities under the High Power Energy (HiPER) Research Group, in the field of renewable electrical power energy harvesting from heat waste and include impedance spectroscopy, thin film technology, plasma technology, density functional theory, advanced functional material development, electrical energy conversion device design, and fabrication. As a senior lecturer in the Electric and Electronic Programme of Faculty Engineering at Universiti Malaysia Sabah, Dr. Megat uses the fundamentals of electrical impedance spectroscopy as the main component of his research and his teaching development, which successfully secured national grant funding, visiting research fellow and international research collaboration, research agreement and consultancy. In 2022, through HiPER, as advisor to the 3rd year Electric and Electronic Integrated Design Project, Dr Megat had brought his team’s prototype entitled "Self-Powered LED System Using Carbon-Based Nanofluid Photothermoelectric Storage" that presented at International Conference on Advances in Manufacturing and Materials Engineering: ICAMME 2022, 9—10 August, Kuala Lumpur, Malaysia and National Innovation and Invention Competition (NIICe) 2022, 22 August, UTHM, Malaysia and awarded with silver medal.
Optoelectronic properties comparison of 10 and 20 multi quantum wells Ga0.952In0.048N0.016As0.984/GaAs p-i-n photodetector for 1.0 μm wavelength
The addition of quantum wells to the intrinsic regions of p-i-n GaInNAs/GaAs has improved the performance of optoelectronic devices. This study reports an optoelectronic properties comparison of different quantum well number for Ga0.952In0.048N0.016As0.984/GaAs-based dilute nitride multi-quantum wells (MQWs) p-i-n photodetector devices. The sample used in this work consists of 10 and 20 undoped QWs p-in Ga0.952In0.048N0.016As0.984 with 10 nm thickness separated by 10 nm GaAs barriers grown on GaAs substrates using molecular beam epitaxy (MBE). This paper’s novelty shows additional rare electrical impedance spectroscopy (EIS) approach to design the p-i-n device optoelectronic. The effect of different MQWs number on the shunt resistance, capacitance, and dielectric loss relaxation that been extracted by the EIS method reveals the electron transport mechanism’s characteristic manifestations in the dark that affect the photodetector performance under illumination.
This study successfully presents a new perspective on the understanding of the optoelectronic properties of the MQWs layer based on impedance analysis to tune the optoelectronic devices based on the understanding of intrinsic electrical properties. From photoluminescence (PL) analysis, 20 MQWs shows a higher PL peak than 10 MQWs. The maximum quantum efficiency (QE) is found to be 80.3% for 20 MQWs and 46% for 10 MQWs, where 20 MQWs being the highest QE value ever reported for GaInNAs-based MQWs photodetector. This study has successfully presented an understanding of optoelectronic properties and simultaneously producing a sensitive photodetector with high quality, low-noise which is comparable with commercial III-V alloy based near-infrared GaAs-based photodetectors.
Further reading:
https://doi.org/10.1016/j.optmat.2022.112272
Application of graphene in energy storage devices
Graphene is a lightweight material in which the carbon atoms are arranged in hexagonal shape in a single layer like a honeycomb pattern. As high electron mobility and high conductivity, graphene also has a large surface area, high thermal conductivity, high mechanical strength, and high optical transmittance. These features have made graphene become a preferred material in energy storage devices, such as lithium-ion batteries, electrical double-layer capacitors, and dye-sensitized solar cells. Graphene is one of the promising electrode ingredients improving the performance of an energy storage device. Thus, this chapter discusses the electrochemical mechanism of graphene for the device perspective.
Further reading:
https://doi.org/10.1016/B978-0-323-85788-8.00019-7
