جستجوی مقالات مرتبط با کلیدواژه « energy storage » در نشریات گروه « شیمی »

Supercapacitors, also known as electric double-layer capacitors, have gained substantial attention for their remarkable energy storage capabilities, making them vital for numerous applications, including portable electronics, electric vehicles, and renewable energy systems. This review delves into the intricate world of carbon electrodes in supercapacitors, highlighting the diverse carbon materials used, such as activated carbons, carbon blacks, zeolite-template carbons, and graphene meso-sponges, and their significant impact on supercapacitor performance. Some research explores the synthesis of carbon electrodes using zeolite templates, which provide precise control over structural properties for enhancing performance in high-rate applications. The review also provides a comprehensive understanding of the fundamental principles of electrochemical cells, emphasizing the critical factors affecting carbon electrode performance, including surface functional groups, electrolyte composition, voltage range and stability, cycle life, operating temperature, current density, and rate capability. Recognizing the interconnected nature of these factors is essential for optimizing supercapacitor technology. This knowledge forms the foundation for ongoing research and innovation needed to advance supercapacitors, providing sustainable and efficient solutions to pressing energy challenges.

Phase Change Materials (PCMs) have recently found a wide range of new application opportunities. In this study, PCMs microcapsules have been synthesized with urea–formaldehyde polymer shell. The microcapsules have been characterized by FT-IR, SEM, TEM, and DSC analysis. Then, the thermophysical characteristics of the MEPCM suspension including the thermal conductivity, and viscosity have been measured at different particle concentration (2, 5 and 10 wt%) and different temperatures from 25 to 50 °C. New correlations are developed to predict the thermophysical characteristics of MEPCM suspensions. This work provides a practical and efficient synthetic strategy for the preparation of MEPCMs, which is expected to present a promising future in the field of energy storage.

Phase Change Materials (PCMs) can be used as thermal energy storage systems in the form of latent heat. These materials are commonly enclosed in a suitable container, in order to prevent leakage of the molten PCM into the surrounding environment. In this study, palmitic acid and polyaniline were used as PCM and polymeric shell, respectively, to prepare a form stable composite. SiO2 nanoparticle was added to the composite to improve the thermal characteristics of the composite. The structure and morphology of the prepared form stable nanocomposite were investigated by Fourier Transform InfraRed (FT-IR) spectroscopy, Field Emission Scanning Electron Microscopy (FE-SEM), and X-Ray Diffract meter (XRD) tests. It was found that the synthesized nanocomposite was fabricated in the form of relatively smooth and compact spherical particles with a size of about 500 nm. Thermal properties of the prepared nanocomposite containing different concentrations of SiO2 nanoparticles were determined using Differential Scanning Calorimetry (DSC) and Thermo Gravimetric Analysis (TGA) tests. It was found that the melting temperature and thermal conductivity of the polyaniline/palmitic acid composite increased by about 16% and 62%, respectively, when combined with 2 wt.% SiO2 nanoparticles. The obtained results revealed that the polyaniline/palmitic acid/2 wt.% SiO2 nanocomposite can be considered a suitable option for thermal energy storage applications.

Copper benzene 1,3,5-tri carboxylates are widely used in research due to their numerous advantages. With abundant resources, excellent catalytic activity, and relatively simple synthetic procedures, Cu MOFs are ideal for activating starting materials and creating complex structural designs. The tunable conditions promote useful reactions such as oxidation, click chemistry, and Friedel-Crafts alkylation. All these properties make Cu MOFs an excellent choice for scientific research. This review provides an overview of this rapidly evolving research field, highlighting novel Cu3(BTC)2 synthesis strategies and Cu3(BTC)2 applications such as electrochemical sensing and metal ion extraction, energy storage, drug delivery, and its role as a catalyst.

The substitution of fossil fuels with renewable energies is a meaningful way to mitigate global warming and air pollution. Phase change materials could store and release a high amount of energy. The solidification phenomenon is an essential factor that should be considered for choosing Phase Change Materials (PCMs). In this work, attempts have been made to improve the thermophysical properties of paraffin as a PCM during the solidification process. 1-3 wt.% of Al2O3, CuO, TiO2, and graphene nanoparticles were used during the solidification process. No reports had yet been made on the effect of graphene nanoparticles versus metal oxide nanoparticles on the thermal properties of Nanoparticle-Enhanced Phase Change Materials (NEPCMs). The DSC, TGA, SEM, and FT-IR analyses were done to investigate the transition temperature, nanoparticle distribution, and nanocomposites morphology, respectively. It was seen that the addition of nanoparticles could effectively increase the thermal conductivities of paraffin. The maximum and minimum increases were in thermal conductivities were recorded in samples with 3wt.% of graphene and 1wt.% of TiO2. The results showed that selecting suitable nanocomposites depended on various parameters, such as the type of nanoparticles and the weight percentage of nanoparticles. The PCM nanocomposites can be used to control the thermal management of different systems. The results can be applied in thermal design and management concepts, especially in the solidification process.

Herein, flyweight organic-inorganic hybrid scaffolds were fabricated by self-assembly and reduction of graphene oxide via covalent reaction of octa(aminophenyl) polyhedral oligomeric silsesquioxane with graphene oxide. Octa(aminophenyl) polyhedral oligomeric silsesquioxane created a decorative coating on the graphene oxide surface. It acts as a nano-crosslinker, especially on the overlapped-zone of graphene oxide platelets to bind them close-fitting. The resulting hybrid hydrogel was transformed into aerogel by the solvent exchange process with liquid carbon dioxide, followed by liquid carbon dioxide supercritical drying. Different concentrations of graphene oxide and octa(aminophenyl) polyhedral oligomeric silsesquioxane were prepared and the structureproperty relationship of obtained aerogels is elucidated. Bulk density and porosity of the aerogels are located between the super-low values of 2.7 to 5.9 mg/cm3 and beyond 99.5 %, respectively. According to the adsorption-desorption isotherms of BET-technique, the surface area of obtained aerogels was in between 250 to 713 m2/g. The findings remark the potential application of obtained aerogels in the production of supercapacitors, lithium-ion batteries, solar cells, etc. in energy storage and conversion devices, electrode materials, sensors, gas/oil/dye adsorbents, and high-temperature insulators in the aerospace industry.