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Summary: Ionic liquids (ILs) are promising solvents for catalytic and electrolyte applications, gas absorption, and extractions in electrochemical systems due to their useful features, such as high conductivity and good thermal, chemical, and electrical stability. This review focuses on incorporating ILs into fuel cell (FC) systems, specifically into two main components of FC (ie, polymer electrolyte membrane and electrocatalyst). In FC, a polymer electrolyte membrane with excellent conductivity and deprived of humidity even at high temperatures must be created for effective early commercialization of this technology. Electrocatalyst performance can also be enhanced with additive materials, such as ILs, thus further improving the entire achievement of FCs. This work discusses the most important reasons for ongoing studies and outlines the current progress in using ILs as a revolutionary form of polymer electrolyte membrane and electrocatalyst. [ABSTRACT FROM AUTHOR]

Summary: Thermal interface materials (TIMs) are applied in electronic devices that are involved in heat generation and raising the temperature. The optimization of TIMs is important in heat dissipation to maintain the good performance of devices, low power during operation, and reduced internal damages among small components. The TIMs are inserted between two contact surfaces to enhance thermal conductivity that will reduce the increment of surface temperature in a longer time and facilitates the cooling process with a consistent power supplied to the system with minimum increment. Research on nanomaterials and hybrid materials aims to obtain maximum thermal conductivity and reduce resistance in the devices. However, the suitable fabrication method for achieving good production and performance is still debatable. Therefore, significant fabrication methods have been explored for various materials. This review provides insights into the current work focusing on the materials used in the development of TIMs by various methods. The discussion begins with the introduction of thermal management and the working principles applied in the system. Then, the methods applied for material fabrication into TIMs, including the advantages and disadvantages of the methods, are discussed. Last, the current challenges and opportunities in methods used are discussed to offer new inputs and improvement in method modification for TIMs design. The targeted thermal performance for the industrial market of TIMs for nanomaterial applications is approximately 100 W/mK and 1 × 10−6 m2/WK with lowest power of 100 W. [ABSTRACT FROM AUTHOR]

Summary: The performance of electronic devices, mostly in medical applications, has been investigated to determine whether they meet the requirements of healthcare monitoring and patient's satisfaction. Mobile health monitoring is preferable at present given the current innovations in handheld, wearable, and implantable devices. However, these applications require appropriate thermal management because they are attached directly to the human body and operate for a long period. Moreover, a sophisticated design with functional mobility necessitates proper thermal circulation during the process. This review provides the current research direction for cooling systems, the thermal working principle of wearable and implantable devices, and its implementation on design architecture. Then, the importance of internal and external functional properties in thermal management and their effects on device performance are discussed. Operating temperature is among the most important elements in monitoring thermal performance due to the tendency of tissue and component damages to occur after an increment of only 1°C or 2°C in temperature. Challenges and available solutions for thermal management are listed in detail to improve cooling methods and service to the healthcare field. [ABSTRACT FROM AUTHOR]

Summary: Carbon quantum dots (CQD) and graphene quantum dots (GQDs) have been mentioned frequently. They have been selected in recent studies as they have unique and remarkable potential, especially in electrical, optical, and optoelectrical properties. CQD and GQDs have very high chemical and physical stability due to inherent inert carbon material, thus newly recognized as a kind of quantum dots material. Its environmentally friendly, non‐toxic, and naturally inactive nature is also a major attraction for scientists around the world. In this work, CQD and GQDs production methods are discussed in detail, including soft‐template method, hydrothermal method, microwave‐assisted hydrothermal (MAH) method, metal‐catalyzed method, liquid exfoliation method, electron beam lithography method, and others. Additive material has been introduced in CQD and GQDs to increase the ability and performance of CQD and GQDs such as nitrogen, sulfur, chlorine, fluorine, and potassium. In particular, the presence of additive material in CQD and GQDs shows an advantage in terms of energy level, which is very good at achieving specific requirements in properties such as optical, electrical, and optoelectrical. In addition, the existence of functional groups consisting of heteroatoms such as oxygen, nitrogen, sulfur, phosphorus, boron, and so on of zero‐dimensional carbon materials in providing an overabundance of the active electrochemical site for the reaction. The product of CQD and GQDs has various shapes and sizes influenced by several parameters such as synthesis temperature, growth time, source concentration, catalyst, and so on. The application of CQDs and GQDs composites in fuel cells has been clearly and scientifically stated as it has enhanced the performance of fuel cell technology. [ABSTRACT FROM AUTHOR]

Summary: The performance of allotrope carbon materials has been explored because of their superior properties in energy system applications. This review provides an understanding of the current work focusing on the applications of selected carbon materials in important energy systems, focus on thermal interface materials (TIMs), and fuel cell applications. This article begins with the introduction of TIMs and fuel cell in general working principle and presents details on carbon materials. The discussion focuses on updates from the latest research work and addresses current challenges and opportunities for research toward TIMs and fuel cell applications. The optimum performance of TIMs was seen when thermal conductivity achieved at a maximum of 3000 W (m K)−1 by using vertically aligned carbon nanotubes (CNTs) and a minimum internal thermal resistance of 0.3 mm2 K W−1. Meanwhile for fuel cell, the platinum/CNTs catalyst applied proton exchange membrane fuel cell achieved high power density of 661 mW cm−2 in the presence of Nafion electrolyte membrane. This review provides insights for scientists about the use of carbon materials, especially in energy system applications. [ABSTRACT FROM AUTHOR]