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Due to its exceptionally high theoretical energy density, fluorinated carbon has been recognized as a strong contender for the cathode material in lithium primary batteries particularly valued in aerospace and related industries. However, CFx cathode with high F/C ratio, which enables higher energy density, often suffer from inadequate rate capability and are unable to satisfy escalating demand. Furthermore, their intrinsic low discharge voltage imposes constraints on their applicability. In this study, a novel and high F/C ratio fluorinated carbon nanomaterials (FNC) enriched with semi-ionic C-F bonds is synthesized at a lower fluorination temperature, using aggregated nanocarbon as the precursor. The increased presence semi-ionic C-F bonds of the FNC enhances conductivity, thereby ameliorating ohmic polarization effects during initial discharge. In addition, the spherical shape and aggregated configuration of FNC facilitate the diffusion of Li+ to abundant active sites through continuous paths. Consequently, the FNC exhibits high discharge voltage of 3.15 V at 0.01C and superior rate capability in lithium primary batteries. At a high rate of 20C, power density of 33,694 W kg-1 and energy density of 1,250 Wh kg-1 are achieved. Moreover, FNC also demonstrates notable electrochemical performance in sodium/potassium-CFx primary batteries. This new-type alkali-metal/CFx primary batteries exhibit outstanding rate capability, rendering them with vast potential in high-power applications. [ABSTRACT FROM AUTHOR]

In lithium–polymer batteries, the electrolyte is an essential component that plays a crucial role in ion transport and has a substantial impact on the battery's overall performance, stability, and efficiency. This article presents a detailed study on developing nanostructured composite polymer electrolytes (NCPEs), prepared using the solvent casting technique. The materials selected for this investigation include poly(vinyl chloride) (PVC) as the host polymer, lithium bromide (LiBr) as the salt, and silica (SiO2) as the nanofiller. The addition of nano-SiO2 dramatically enhanced the ionic conductivity of the electrolytes, with the highest value of 6.2 × 10−5 Scm−1 observed for the sample containing 7.5 wt% nano-SiO2. This improvement is attributed to an increased amorphicity resulting from the interactions between the polymer, salt, and filler components. A structural analysis of the prepared NCPEs using X-ray diffraction revealed the presence of both crystalline and amorphous phases, further validating the enhanced ionic transport. Additionally, the thermal stability of the NCPEs was found to be excellent, withstanding temperatures up to 334 °C, thereby reinforcing their potential application in lithium–polymer batteries. This work explores the electrochemical performance of a fabricated lithium-ion-conducting primary electrochemical cell (Zn + ZnSO4·7H2O|PVC: LiBr: SiO2|PbO2 + V2O5), which demonstrated an open circuit voltage of 2.15 V. The discharge characteristics of the fabricated cell were thoroughly studied, showcasing the promising potential of these NCPEs. With the support of superior morphological and electrical properties, as-prepared electrolytes offer an effective pathway for future advancements in lithium–polymer battery technology, making them a highly viable candidate for enhanced energy storage solutions. [ABSTRACT FROM AUTHOR]

Dielectric barrier discharge (DBD) nonthermal plasma is applied for the gasification of kitchen waste. The gas production performance of kitchen waste gasification based on DBD under different reaction ambientes is studied. Density functional theory (DFT) simulations are used to investigate the gas production mechanism via glucose and aspartate. Scanning electron microscopy (SEM) and Raman spectroscopy are used to investigate the physicochemical properties of the produced carbon materials and reveal the plasma reaction mechanism. The plasma treatment of millet and soybean has good gasification effect and can inhibit tar production. N2 and CO2 ambientes are more conducive to the gasification of millet and soybean. The H2 concentration in plasma‐treated millet gasification under plasma in N2 ambient can reach 4%. Glucose is finally decomposed through ring‐opening reaction, decarbonylation reaction, dehydration reaction, and carbon–carbon bond breaking. And the decomposition process of aspartic acid mainly includes decarbonylation and deammonia reaction. With the increase of gas ionization energy, the surface pore structure of the carbon material after plasma treatment is more developed, which indicates that the reaction between plasma and solid is on a layer by layer basis with the solid surface facing the inner surface. This paper aims to provide valuable theoretical support for the application of DBD in the treatment of kitchen waste. [ABSTRACT FROM AUTHOR]

Thermal storage ceramics using metals as phase change materials (PCMs) have both high thermal conductivity and high heat storage density. However, in the process of use is very easy to occur in the metal phase change material leakage, will seriously affect the service life of the thermal storage ceramics. In this study, ceramic composite phase change heat storage materials with Al-12Si alloy as phase change material were prepared. Firstly, Al-12Si was pretreated by sol-gel method and high temperature heat treatment to obtain the pretreated Al-12Si alloy powder with dense alumina shell layer. Afterthat, the pretreated Al-12Si alloy powder was mixed and pressed with alumina, silicon dioxide, magnesium oxide, and mullite respectively, and sintered at 1,100°C, 1,200°C, or 1,300°C. The experimental results show that the metal phase change materials and the four ceramic materials show good chemical compatibility, and pretreated Al-12Si essentially retains its initial shape and is uniformly dispersed in the heat storage material. Among all the samples, the pre-treated Al-12Si/mullite ceramic thermal storage materials with a sintering temperature of 1,200°C showed the best thermal storage performance. The thermal conductivity of the samples was up to 17.94 W/(m-K). The latent heat storage value was 139.51 J/g before thermal cycling, 138.27 J/g after 100 thermal cycling, which was only decreased by 0.89%, and there was almost no alloy leakage. This study has successfully realized that the ceramic thermal storage material possesses high thermal conductivity, high thermal storage density and excellent thermal cycling performance at the same time, and provides a new method for the production and preparation of Al-12Si/ ceramic heat storage materials, which has great potential for application in heat storage systems. [ABSTRACT FROM AUTHOR]

Due to their distinctive security characteristics, all-solid-state batteries are seen as a potential technology for the upcoming era of energy storage. The flexibility of nanomaterials shows enormous potential for the advancement of all-solid-state batteries' exceptional power and energy storage capacities. These batteries might be applied in many areas such as large-scale energy storage for power grids, as well as in the creation of foldable and flexible electronics, and portable gadgets. The most difficult aspect of creating a comprehensive nanoscale all-solid-state battery assembly is the task of decreasing the particle size of the solid electrolyte while maintaining its excellent ionic conductivity. Materials possessing nanoscale structural features and a substantial electrochemically active surface area have the potential to significantly enhance power characteristics and the cycle life. This might bring about substantial changes to existing energy storage models. The primary objective of this research is to summarize the latest advancements in utilizing nanomaterials for energy harvesting in various all-solid-state battery assemblies. This study examines the most complex solid–solid interfaces of all-solid-state batteries, as well as feasible methods for implementing nanomaterials in such interfaces. Currently, there is significant attention on the necessity to develop electrode–solid electrolyte interfaces that exhibit nanoscale particle articulation and other characteristics related to the behavior of lithium ions. [ABSTRACT FROM AUTHOR]

In this work, the first‐principles study based on density functional theory was applied to investigate the geometries, electronic structures, and optical properties in four directions of the Si‐NWs surface, which are modified by oxygen atoms. The results show that the geometries, band structures, and optical properties of the Si‐NWs are affected by the modification of oxygen atoms. The Si─Si bonds adjacent to the region modified by oxygen atoms elongate, the cell volumes decrease, while the energy gaps of Si‐NWs narrow. Evident impurity bands appear on the energy bands of the modified Si‐NWs, forming S═O double bonds. A blue shift of the perpendicular component spectra of the dielectric constant relative to parallel spectra can be observed for Si [100]‐NW, Si [111]‐NW, and Si [112]‐NW. At the same time, the real and imaginary parts of the dielectric function spectra of all Si‐NWs are red‐shifted after the modification by oxygen atoms, and the spectra of Si [111]‐NWs forming Si═O double bonds are the most significant red‐shifted. These results can provide a theoretical reference for preparing nano‐silicon optoelectronic materials and devices. [ABSTRACT FROM AUTHOR]

Prussian blue and Prussian blue analogues have attracted increasing attention as versatile framework materials with a wide range of applications in catalysis, energy conversion and storage, and biomedical and environmental fields. In terms of energy storage and conversion, Prussian blue-based materials have emerged as suitable candidates of growing interest for the fabrication of batteries and supercapacitors. Their outstanding electrochemical features such as fast charge–discharge rates, high capacity and prolonged cycling life make them favorable for energy storage application. Furthermore, Prussian blue and its analogues as rechargeable battery anodes can advance significantly by the precise control of their structure, morphology, and composition at the nanoscale. Their tunable structural and electronic properties enable the detection of many types of analytes with high sensitivity and specificity, and thus, they are ideal materials for the development of sensors for environmental detection, disease trend monitoring, and industrial safety. Additionally, Prussian blue-based catalysts display excellent photocatalytic performance for the degradation of pollutants and generation of hydrogen. Specifically, their excellent light capturing and charge separation capabilities make them stand out in photocatalytic processes, providing a sustainable option for environmental remediation and renewable energy production. Besides, Prussian blue coatings have been studied particularly for corrosion protection, forming stable and protective layers on metal surfaces, which extend the lifespan of infrastructural materials in harsh environments. Prussian blue and its analogues are highly valuable materials in healthcare fields such as imaging, drug delivery and theranostics because they are biocompatible and their further functionalization is possible. Overall, this review demonstrates that Prussian blue and related framework materials are versatile and capable of addressing many technical challenges in various fields ranging from power generation to healthcare and environmental management. [ABSTRACT FROM AUTHOR]

In this current study, hydrothermal method was employed to synthesize distinct nanostructures: pure nickel oxide (NiO), Zn‐doped NiO, and NiO/ZnO composites. X‐ray diffraction (XRD) results confirmed NiO's cubic structure, with sizes of 17.01 nm for pure NiO and 30.87 nm for composites. Scanning electron microscope (SEM) images revealed flowerlike morphologies, energy‐dispersive X‐ray spectroscopy (EDX) authenticated the elemental composition without any impurities. Ultraviolet–visible (UV‐Vis) spectroscopy demonstrated heightened absorption in doped and nanocomposite samples. The bandgap energy calculated using Tauc's plot reduced from 2.95 to 2.55 eV with increase in zinc (Zn) content. In Fourier‐transform infrared (FTIR) characterization, the Ni–O stretching vibration appeared at 666.7 cm−1 in doped samples, while Zn–O stretching was evident at 586.03 cm−1. Photoluminescence analysis unveiled a strong peak at 470 nm (near band edge) and another at 665 nm (indicative of defects), exhibiting intensified signals in doped and nanocomposite samples due to a higher defect density. The dielectric constant showed increased values at low frequencies attributed to real and space charge polarization. Notably, the conductivity of Zn‐doped and nanocomposite samples displayed an upward trend with frequency due to a higher defect density. This study unveils insights into the intricate optical and electrical properties of these novel nanostructures, showcasing their potential in advanced energy storage applications. [ABSTRACT FROM AUTHOR]

The bismuth (Bi)-substituted CuSb1-xBixSe2 chalcostibites were synthesized using the horizontal Bridgman-Stockbarger technique combined with ball milling, at temperatures ranging from 303 to 650 K. The impact of Bi substitution was observed in the thermoelectric transport properties by substituting Bi (x = 0, 0.2, 0.4, 0.6) resulted in a decreased Seebeck coefficient and higher electrical resistivity compared to the pure CuSbSe2 sample. Notably, the higher substitution level (x = 0.6) showed the enhanced properties compared to the lower levels. The pristine sample exhibited a power factor of 550 μWK−2 m−1, while the substituted samples showed the values of 20, 37 and 50 μWK−2 m−1, respectively. However, in accordance with the power factor, the pristine compound demonstrated a higher figure of merit (ZT = 0.47) compared to the existing literature values (ZT = 0.21), indicating the superior thermoelectric performance using this synthesis method. [ABSTRACT FROM AUTHOR]