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Nanocatalysts have emerged as promising candidates for enhancing the performance of Direct Liquid Fuel Cells (DLFCs). These fuel cells directly convert the chemical energy stored in liquid fuels into electrical energy. Nanocatalysts, characterized by their nanoscale size and high surface area, offer unique advantages for catalytic reactions in DLFCs. This review provides an overview of the role and potential of nanocatalysts in DLFCs. Nanocatalysts are often combined with suitable support materials like carbon aerogels or metal oxides to enhance conductivity and stability. The utilization of nanocatalysts in DLFCs offers several benefits. The enhanced catalytic activity and improved reaction kinetics contribute to higher power output and fuel utilization efficiency. Nanocatalysts also broaden the range of liquid fuels that can be used, thereby increasing the versatility of DLFCs. The goal of improving catalyst efficiency has been the focus of contemporary research. DLFCs utilize nanocatalysts, which are tiny metal particles supported by metal oxides or nanocarbons like ruthenium and platinum. This study explores into their structure, support networks, and synthesis challenges, providing a comprehensive exploration of nanocatalyst advancements in DLFCs. Improving DLFC performance and efficiency involves investigating these nanocatalysts. By tackling current challenges, nanocatalysts hold the promise to transform DLFCs and play a pivotal role in advancing clean energy conversion technologies. [ABSTRACT FROM AUTHOR]

This review discusses the impact of alpha‐gallium oxide (α‐Ga2O3) on potential high‐power device applications. To date, there are high requirements for efficient high‐power delivery and low‐power loss device material in power industries. III‐VI oxide semiconductor family, α‐Ga2O3, is recognized as a promising, future power semiconductor material owing to its ultrawide bandgap of 5.3 eV, high breakdown field of 10 MV cm−1, and a large Baliga's figure of merit. A highly expected α‐Ga2O3 power semiconductor electronic device (Schottky barrier diode and field effect transistor) can perform better than conventional semiconductor materials Si, SiC, and GaN. However, there is a lack of research into using mist CVD to cultivate high‐quality α‐Ga2O3 for high‐power devices like FETs and SBDs. Currently, the mist CVD‐grown α‐Ga2O3 thin film power device is still in its early stages, and one of the main reasons for this is defects of the thin film, which impede material electron mobility. The purpose of writing this article is to provide an overview of the development of α‐Ga2O3 heteroepitaxial thin film by the mist CVD process for use in high‐power devices such as Schottky barrier diodes (SBD) and field effect transistors (MOSFET). 1. α‐Ga2O3 α‐Ga2O3. Furthermore, multiple viewpoints highlight the challenges and future trends toward device performance sustainability in a scientific society. [ABSTRACT FROM AUTHOR]

This review provides the recent advances in triglyceride catalytic pyrolysis using heterogeneous dolomite catalysts for upgrading biofuel quality. The production of high-quality renewable biofuels through catalytic cracking pyrolysis has gained significant attention due to their high hydrocarbon and volatile matter content. Unlike conventional applications that require high operational costs, long process times, hazardous material pollution, and enormous energy demand, catalytic cracking pyrolysis has overcome these challenges. The use of CaO, MgO, and activated dolomite catalysts has greatly improved the yield and quality of biofuel, reducing the acid value of bio-oil. Modifications of the activated dolomite surface through bifunctional acid–base properties also positively influenced bio-oil production and quality. Dolomite catalysts have been found to be effective in catalyzing the pyrolysis of triglycerides, which are a major component of vegetable oils and animal fats, to produce biofuels. Recent advances in the field include the use of modified dolomite catalysts to improve the activity and selectivity of the catalytic pyrolysis process. Moreover, there is also research enhancement of the synthesis and modification of dolomite catalysts in improving the performance of biofuel yield conversion. Interestingly, this synergy contribution has significantly improved the physicochemical properties of the catalysts such as the structure, surface area, porosity, stability, and bifunctional acid–base properties, which contribute to the catalytic reaction's performance. [ABSTRACT FROM AUTHOR]

The heat transfer performance in materials to remove heat is attained in various designs according to the devices' design. Simulation studies are comprising of heat transfer knowledge in detail suit the theories and applications. This review provides an understanding of the simulation work focusing on the heat transfer in the various design of electronic devices. This discussion begins with a briefing on the simulation principle and current focus. Then, the review continues by explaining various simulation methods that exhibit recent heat transfer analysis. The properties of simulation studies are also summarized in detail to understand the significant properties that impact analysis. The application of simulation in thermal model is looked forward to obtain significant heat transfer improvement and impactful research direction. This review also provides insights into challenges in simulation work with available opportunities to solve the heat transfer issue by understanding fundamental knowledge. [ABSTRACT FROM AUTHOR]

With the ever‐increasing danger of climate change, power plants are shifting from polluting fossil fuels to sustainable bioenergy fuels. As Malaysia continues to pledge to decrease glasshouse gas (GHG) emissions, quick and dramatic action should resolve the reliance on fossil fuel power plants. Furthermore, the coal‐fired power station is Malaysia's biggest supplier of energy and the final power plant to be decommissioned. In Malaysia, a significant portion of palm oil biomass has the potential to replace coal in the generation of renewable energy power. However, the deployment of palm oil biomass as a renewable energy source has not been fully achieved. Furthermore, the surplus of unutilized biomass from the palm oil milling process has emerged as the key talking point leading to environmental concerns. As estimated, this palm oil biomass can generate approximately 5000 MW of electricity under 40% of operation efficiency. This significant power potential has the ability to replace Malaysia's yearly reliance on coal. Nonetheless, the limitations of technological stability, budgetary constraints, and other government policy concerns have prevented the potentials from being fulfilled. This necessitates an integrated framework that synergizes the decarbonization drive in order to realize the primary advantages of energy renewability and carbon neutrality. Among the suggested actions to decarbonize the power generating sector is an integrated scheme of palm oil production, biogas plant for electricity and steam generation, and biofuel pellet manufacture. This review provides an in‐depth overview of palm oil biomass for Malaysian power production decarbonization. This article is categorized under:Sustainable Energy > BioenergyClimate and Environment > Net Zero Planning and DecarbonizationSustainable Development > Emerging Economies [ABSTRACT FROM AUTHOR]

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: Direct liquid fuel cell (DLFC) is one of the leading fuel cell types due to their great features of superior energy density, modest configuration, small size in fuel container, immediate boosting, and effortless storage and carriage. Commercially used liquid fuel types are prepared using alcohols, such as methanol or ethanol, glycol, and acids. DLFCs face great challenges although they are potentially far‐reaching depending on the expensive catalysts and the use of high‐loading catalyst. More questions that should be addressed to ensure excellent DLFC performance include cathode flooding, fuel crossover, numerous side yield production, fuel security, and unverified elongated‐duration robustness. Further studies need to be carried out to ensure the continuous improvement of the quality of DLFCs' performance and their penetration in the commercial market. To date, direct liquid fuel cells made of methanol and ethanol have been successfully produced in commercial scale, but other types of DLFCs are still under study. In this review, introduction to DLFC will be discussed by covering work and commercialization as well as recent progress and challenges encountered. [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: This review provides a deep insight into the advanced polymer composite developed in fuel cell application. Organic polymer combined with inorganic filler has produced a new material known as a hybrid membrane or composite membrane. This combination has enhanced the various characteristics including conductivity properties, membrane permeability, and stability, cheaper, optimum water retention and mechanical properties. Properties of the hybrid membrane are influenced totally by several factors such as membrane preparation techniques as well as internal properties of particles involved, for example, inorganic fillers such as the size and type of particles, surface alkaline or acidity, shape and formation of networking between the polymer phase. The conventional membrane used in the fuel cell application is Nafion. Nafion potential is undoubtedly in obtains of high conductivity, but it faces some major problems such as CO poisoning, high cost, fuel crossover and water management that needs to be taken seriously. Hybrid composite is seen as an alternative material to addressing problems faced by a conventional membrane but promises even better potential if explored in depth. In this article, all inorganic fillers involved in the production of the composite membranes have been discussed comprehensively. Different types of polymers have been categorized with various fillers. [ABSTRACT FROM AUTHOR]

Summary: The industrial revolution development of electronic technologies has turned the electronic system into a complicated integration of high‐power density and smart design. The complex integrated design has contributed to the excessive heat generation in electronic devices. Consequently, heat management devices have become crucial in prolonging the lives of devices and components and maintaining their optimal performance. Therefore, the passive heat management treatment through thermal interface materials (TIMs) in the devices is among the best options to remove heat from electronic devices. Carbon nanotubes (CNTs) with high‐thermal conductivity was employed in this study for TIM development by using the simple electrophoretic deposition (EPD) method. The CNTs were synthesized and purified before TIM development. Several analyses, including transmission electron microscopy, thermogravimetric analysis, Raman spectroscopy, and Fourier‐transform infrared, were conducted. Analysis results showed that only 0.03 wt% was retained and carbon content increased up to 97.84% after purification. The purified CNTs were dissolved in a suspension medium with a ratio of 0.5 mg/mL to achieve suspension stability, and a Zetasizer was used for verification. The following three operating parameters of EPD were investigated: (a) range of applied voltage (100‐200 V), (b) deposition time (1‐20 min), and (c) gap between electrodes (10‐20 mm). On the basis of the characterization results, the optimum process condition of EPD was achieved at 175 V, 10 minutes, and 10 mm with 1.6 mg of CNT deposition and 14.14 μm of CNT thickness. The maximum thickness of deposited CNTs was 56.95 μm, producing 27.08 W/m∙K and 2.09 mm2/s of thermal conductivity and diffusivity, respectively. These results indicate the high potential of CNTs in facilitating efficient heat removal in TIM fabrication. [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]

Thermal interface materials (TIM) involve heat removal from electronic devices. It is used to remove heat sink from the heat sources to prolong the operation system of a device. It normally replaces the thermally insulated air between the two surfaces and uses it as a secondary thermal conductive material. The current thermal conductivity of TIM is considered to be a limitation for the development of advance electronic devices. In this study, the performance of carbon nanotubes (CNTs) which were used as TIM was investigated by using electrophoretic deposition method. The deposition of CNTs was varied from one to six layers and the performance of deposition was evaluated. The stable suspension of CNTs in DMF with zeta potential reading of -35.87 mV give rise to a smooth and uniform deposition on nickel plated copper substrate (heat spreader) with the usage of electrophoretic deposition (EPD). Maximum layers of CNTs deposition were obtained at six layers with 56.95 µm of deposition thickness and 11.0 mg of deposition weight. Thermal conductivity was measured using a thermal analyser while the thickness of deposition was observed using scanning electron microscope (SEM). The employment of CNTs improved the heat removal of TIM with thermal conductivity reading of 27.08 W m-1 K-1. Optimisation studies revealed that EPD operated at an applied voltage of 175 V coupled with 10 min deposition time produced a single layer deposition with the thickness of 14.14 µm. [ABSTRACT FROM AUTHOR]

The crystal structure, electron charge density, band structure, density of states, and optical properties of pure and strontium (Sr)-doped β-Ga2O3 were studied using the first-principles calculation based on the density functional theory (DFT) within the generalized-gradient approximation (GGA) with the Perdew–Burke–Ernzerhof (PBE). The reason for choosing strontium as a dopant is due to its p-type doping behavior, which is expected to boost the material's electrical and optical properties and maximize the devices' efficiency. The structural parameter for pure β-Ga2O3 crystal structure is in the monoclinic space group (C2/m), which shows good agreement with the previous studies from experimental work. Bandgap energy from both pure and Sr-doped β-Ga2O3 is lower than the experimental bandgap value due to the limitation of DFT, which will ignore the calculation of exchange-correlation potential. To counterbalance the current incompatibilities, the better way to complete the theoretical calculations is to refine the theoretical predictions using the scissor operator's working principle, according to literature published in the past and present. Therefore, the scissor operator was used to overcome the limitation of DFT. The density of states (DOS) shows the hybridization state of Ga 3d, O 2p, and Sr 5s orbital. The bonding population analysis exhibits the bonding characteristics for both pure and Sr-doped β-Ga2O3. The calculated optical properties for the absorption coefficient in Sr doping causes red-shift of the absorption spectrum, thus, strengthening visible light absorption. The reflectivity, refractive index, dielectric function, and loss function were obtained to understand further this novel work on Sr-doped β-Ga2O3 from the first-principles calculation. [ABSTRACT FROM AUTHOR]

Gallium oxide (Ga2O3) is a promising wide-band-gap semiconductor material for UV optical detectors and high-power transistor applications. The fabrication of p-type Ga2O3 is a key problem that hinders its potential for realistic power applications. In this paper, pure α-Ga2O3 and Ca-doped α-Ga2O3 band structure, the density of states, charge density distribution, and optical properties were determined by a first-principles generalized gradient approximation plane-wave pseudopotential method based on density functional theory. It was found that calcium (Ca) doping decreases the bandgap by introducing deep acceptor energy levels as the intermediate band above the valence band maximum. This intermediate valence band mainly consists of Ca 3p and O 2p orbitals and is adequately high in energy to provide an opportunity for p-type conductivity. Moreover, Ca doping enhances the absorptivity and reflectivity become low in the visible region. Aside, transparency decreases compared to the pure material. The optical properties were studied and clarified by electrons-photons interband transitions along with the complex dielectric function's imaginary function. [ABSTRACT FROM AUTHOR]

This article provides an overview of the structural and physicochemical properties of stable carbon-based nanomaterials and their applications as counter electrodes (CEs) in dye-sensitized solar cells (DSSCs). The research community has long sought to harvest highly efficient third-generation DSSCs by developing carbon-based CEs, which are among the most important components of DSSCs. Since the initial introduction of DSSCs, Pt-based electrodes have been commonly used as CEs owing to their high-electrocatalytic activities, thus, accelerating the redox couple at the electrode/electrolyte interface to complete the circuit. However, Pt-based electrodes have several limitations due to their cost, abundance, complicated facility, and low corrosion resistance in a liquid electrolyte, which further restricts the large-area applications of DSSCs. Although carbon-based nanostructures showed the best potential to replace Pt-CE of DSSC, several new properties and characteristics of carbon-CE have been reported for future enhancements in this field. In this review, we discuss the detailed synthesis, properties, and performances of various carbonaceous materials proposed for DSSC-CE. These nano-carbon materials include carbon nanoparticles, activated carbon, carbon nanofibers, carbon nanotube, two-dimensional graphene, and hybrid carbon material composites. Among the CE materials currently available, carbon-carbon hybridized electrodes show the best performance efficiency (up to 10.05%) with a high fill factor (83%). Indeed, up to 8.23% improvements in cell efficiency may be achieved by a carbon-metal hybrid material under sun condition. This review then provides guidance on how to choose appropriate carbon nanomaterials to improve the performance of CEs used in DSSCs. [ABSTRACT FROM AUTHOR]

Nanostructured metal oxide semiconductors have emerged as promising nanoscale photocatalysts due to their excellent photosensitivity, chemical stability, non-toxicity, and biocompatibility. Enhancing the photocatalytic activity of metal oxide is critical in improving their efficiency in radical ion production upon optical exposure for various applications. Therefore, this review paper provides an in-depth analysis of the photocatalytic activity of nanostructured metal oxides, including the photocatalytic mechanism, factors affecting the photocatalytic efficiency, and approaches taken to boost the photocatalytic performance through structure or material modifications. This paper also highlights an overview of the recent applications and discusses the recent advancement of ZnO-based nanocomposite as a promising photocatalytic material for environmental remediation, energy conversion, and biomedical applications., (© 2024 IOP Publishing Ltd.)