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High voltage (HV) outdoor insulators are subjected to both electrical and environmental stresses, which may lead to their failure. Among the causes, corona discharge, humidity and UV radiation are considered to be the most damaging factors. Efforts are therefore underway to investigate new materials for improving the performance of insulating systems. In this research work, silicone-based room temperature vulcanized samples filled with alumina trihydrate (ATH), silicon dioxide and magnesium hydroxide (MH) were prepared and exposed to AC corona discharge for a duration of 110 h. The electric discharge was also accompanied by UV radiation and two different humidity levels. Following aging of the test samples, diagnosis was conducted to assess their integrity. Measurements based on determining the static contact angle demonstrated the loss of hydrophobicity of all the materials, while hydrophobicity recovery phenomena revealed that ATH-doped materials demonstrated a comparatively higher increase in the contact angle than in samples filled with silicone dioxide (silica) and MH. Scanning electron microscopy analysis revealed deep cracks and block-like structures on their surfaces. Similarly, energy-dispersive X-ray analysis indicated the signs of surface oxidation of the aged samples. However, the data of elemental composition exhibited the loss of filler contents as well as that of carbon from the base matrix. The overall assessment showed that resistance to suppress aging is influenced by both the filler type and its concentration in the investigated composites. The ATH-filled composites exhibited outstanding performance when exposed to the rigors of corona discharge and other environmental stresses. This research contributes to materials science and HV engineering by addressing the development of composites for enhanced insulator performance, with future aspects lying in the utilization of nano-composites for advanced functionality and durability.

The Ni1−x CuxFe2O4 (where x = 0, 0.05, 0.10, 0.15) nano ferrite powder was synthesized through chemical co-precipitation method, NaOH and acid oleic as raw materials. The XRD patterns confirmed the spinal structure phase purity of materials. XRD results showed that lattice parameter decreases with the increase of copper concentration by increasing copper concentration in the parent material. Scanning electron microscopy (SEM) was used to determine the morphology and particle size. SEM analysis indicated that all the samples are in nano size and homogeneous. AC electrical properties of nanoparticles were investigated by employing impedance spectroscopy. The real and the imaginary parts of impedance, permittivity, modulus along with the real part of ac conductivity, and tan delta were measured and analyzed for all synthesized samples in 1 Hz to 7 MHz for different voltages at 300 K.

Electrode materials comprising SnO2 quantum dots embedded within ZnO hexagonal prisms were successfully synthesized for building cost-effective energy-storage devices. Extensive structural and functional characterizations were performed to assess the electrochemical performance of the electrodes. SEM–EDS results confirm a uniform distribution of SnO2 quantum dots across ZnO. The integration of SnO2 quantum dots with ZnO hexagonal prisms markedly improved the electrochemical behavior. The analysis of electrode functionality conducted in a 3 M KOH electrolyte revealed specific capacitances of 949.26 and 700.68 F g⁻1 for SnO2@ZnO and ZnO electrodes, respectively, under a current density of 2 A g⁻1. After undergoing 5,000 cycles at a current density of 15 A g⁻1, the SnO2@ZnO and ZnO electrodes displayed impressive cycling stability, maintaining specific capacitance retention rates of 89.9 and 92.2%, respectively. Additionally, a symmetric supercapacitor (SSC) device constructed using the SnO2@ZnO electrode showcased exceptional performance, exhibiting a specific capacitance of 83 F g⁻1 at 1.2 A g⁻1. Impressive power and energy densities were achieved by the device, with values reaching 2,808 and 70.2 W kg⁻1, respectively. Notably, the SnO2@ZnO SSC device maintained a capacity preservation of 75% throughout 5,000 galvanostatic charge–discharge sequences. The outcomes highlight the potential of SnO2@ZnO hexagonal prisms as candidates for energy-storage applications, offering scalability and cost-effectiveness. The proposed approach enhances the electrochemical performance while ensuring affordability, facilitating the creation of effective and financially feasible energy storage solutions.

The synthesis of zeolite nanoparticles is studied comprehensively by adding an organic template as a reflux method, extracted from crystals. The zeolite nano-crystals are quite effectively synthesized by incorporating silica, organic template, and alkali metal. The tetrapropylammoniumhydroxide, tetrapropylammoniumbromide and tetraethyl orthosilicate (TEOS) as organic templates are added for the assistance of zeolite (albite) crystals. A cross-linker TEOS is also mixed. Adding carbon nanotubes and graphene oxide made the morphology of albite more interesting. Nucleation time is an important feature for the formation of albite crystals. The albite nano-shaped crystal is developed for instance when reaction time is less than 240 h, after this period crystal size increases with time. Batch 1 of zeolite is prepared with additives for testing its morphology, like surface area, particle size shape, and crystal geometry. The general trend (e.g., pore volume, percentage composition, particle size, geometry) of zeolite nano-crystal is explained by the help of robust techniques such as Fourier transform infrared spectroscopy, X-ray diffraction, Brunauer–Emmett–Teller, energy-dispersive X-ray spectroscopy, and scanning electron microscopy.

Hydroxyapatite/magnetite (HA-Fe3O4) nanocomposite materials that have the synergistic ability to produce heat when in direct bonding with a bone through HA are regarded competent hyperthermia therapies of bone carcinoma treatment. HA-Fe3O4 nanocomposites with various magnetite concentrations (10, 20, and 30 wt%) were quickly synthesized using a novel continuous microwave-assisted flow synthesis (CMFS) process in a 5 min residence duration at the conditions of pH 11. In this process, initially, phase pure hydroxyapatite and superparamagnetic magnetite nanoparticles followed by a series of HA-Fe3O4 nanocomposites were formed, without a subsequent aging step. The obtained nano-product was physically analyzed using Brunauer-Emmett-Teller (BET) surface area analysis, transmission electron microscopy, and X-ray powder diffraction analysis. X-ray photoelectron spectroscopy was used for the chemical structure analysis of the final nanocomposite product. Zeta potential measurements were carried out to determine colloidal stability associated with the surface charge of the nanocomposites. The magnetic properties were determined using a vibrating sample magnetometer. The results indicated the high magnetization property of the obtained nanoproduct, suitable for hyperthermia application. HA-Fe3O4 nanocomposites have shown remarkable antimicrobial properties against E. coli and S. cerevisiae. Thus, the CMFS system facilitated the rapid production of HA-Fe3O4 nanocomposite particles with fine particle size.

Antibiotics are resistant compounds that become emerging contaminants that cause hazards to human health and the ecological environment due to their wide production and consumption. The present research reveals the remediation of amoxicillin (AMX) antibiotic by catalytic degradation using fabricated zinc oxide (ZnO) and zinc oxide-reduced graphene oxide (ZnO-rGO) catalysts. The characterization of the catalyst was carried out via UV–Vis spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, energy dispersive X-ray spectroscopy, and scanning electron microscopy to evaluate the morphology and composition of synthesised catalyst. The catalytic ability of ZnO-rGO and ZnO was investigated by analysing the degradation of AMX. The ZnO-rGO nanocomposites (NCs) showed improved catalytic performance towards AMX degradation (96%) than pure ZnO nanoparticles (85%), which may be attributed to the incorporation of rGO, which enhanced the adsorption rate and changed the electron–hole recombination rate. The antioxidant potential of synthesised nanomaterials was also analysed by three different methods. The adsorption behaviour was explained through the Langmuir and Freundlich models, and the results revealed that AMX adsorption followed the Freundlich model more closely for both catalysts. The adsorption of AMX was also studied thermodynamically at different temperatures. The negative Gibbs energy change, positive enthalpy change, and entropy change showed the reaction’s spontaneity and endothermic nature. Finally, it can be assumed that the ZnO-rGO NCs could be an effective semiconductor for the degradation of AMX from wastewater.

This research endeavors to advance the anti-corrosive characteristics, mainly the physico-mechanical properties, by incorporating graphene oxide (GO) into a polyimide (PI) matrix. So, a nanocomposite coating is fabricated for an aluminum alloy substrate. Results reveal that the coating was uniformly dispersed across the surface signifying that the inclusion of GO increased the PI dispersion. The π–π stacking interactions between the aromatic rings of PI and GO contribute to their stability and improved anticorrosive properties. The incorporation of GO to PI films significantly enhances hydrophobicity, as evidenced by the increased contact angles. Assessing the corrosion resistance of the coating in a 3.5 wt% NaCl solution through electrochemical impedance spectroscopy and potentio-dynamic polarization establishes a prominent correlation between the percentage of GO and the anticorrosion efficiency of the composite coating. Precisely, the nanocomposite coating containing 5 wt% GO exhibits an impressive impedance modulus value of 107, and the corrosion current density (I cor) is drastically reduced by over three orders of magnitude, reaching 4.8 × 10−9 A cm−2, as indicated by the polarization curve. Also, prolonged immersion tests confirm the exceptional protective ability of the S5 coating (5 wt% GO), effectively shielding the metal for up to 100 h. After conducting diagnostic measurements, the hybrid nanocomposites of GO/PI examined in this study showcased their effectiveness as inhibitors in anticorrosive coatings. These composites played a vital role to hinder the oxidation of underlying aluminum alloy when exposed to oxidizing chemicals, water, or air, thereby extending the protective duration.

Zinc-ion supercapacitors (ZISCs) exhibit great potential to store energy owing to the benefits of high power density and environmentally friendly features. However, solving the drawbacks of low specific energy and poor cyclic performance at high current rates is necessary. Thus, developing better cathode materials is a practical and efficient way to overcome these limitations. This work presents an encouraging design of two-dimensional (2D) graphite ultrathin nanosheets (GUNSs) as a cathode material for ZISCs. The experimental results show that the GUNSs-based cathode material exhibits a wide surface area and rapid charge transformation features. The 2D GUNS as a cathode was tested in three-electrode systems, and it provided an exceptionally high capacitance of 641 F/g at 1 A/g in an aqueous ZnSO4 electrolyte, better than GUNS-N2 (462 F/g at 1 A/g) and pristine graphite (225.8 F/g at 1 A/g). The 2D GUNS has a rate performance of 43.8% at a current density of 20 A/g, better than GUNS-N2 (35.6%) and pristine graphite (8.4%) at the same conditions. Furthermore, a ZISC device was fabricated using GUNSs as cathode and Zn-foil as anode with 1 M ZnSO4 electrolyte (denoted as GUNSs//Zn). The as-fabricated GUNSs//Zn device exhibits an excellent capacitance of 182.5 F/g at 1 A/g with good capacitance retention of 97.2%, which is better than pristine graphite (94.6%), and nitrogen-doped GUNS (GUNS-N2) cathode (95.7%). In addition, the GUNSs//Zn device demonstrated an ultrahigh cyclic life of 10,000 cycles, and 96.76% of capacitance was maintained. Furthermore, the GUNSs//Zn device delivers a specific energy of 64.88 W h/kg at an ultrahigh specific power of 802.67 W/kg and can run a light-emitting diode for practical applications.

There are numerous problems in the world, but environmental pollution is the biggest threat to life. Air pollution is the most critical form of environmental pollution because air is the most essential need of life. However, industrialization, population growth, and fossil fuel use increase hazardous and greenhouse gas concentrations daily. Greenhouse gases like carbon dioxide (CO2) contribute to global warming; hence, efficient, inexpensive, sustainable, and ecologically friendly air purification solutions are required. This study proposed a new method for synthesizing N- and P-rich polyphosphazene-based hyper cross-linked polymer (HCP) for CO2 adsorption. Due to their persistent porosity, low density, and high surface area, hyper cross-linked porous organic–inorganic hybrid phosphorus and nitrogen-rich polymers are cost-effective and promising gas adsorption materials. We synthesized hybrid organic and inorganic polyphosphazenes with nitrogen and phosphorus backbones and aromatic side groups cross-linked by the Friedel–Crafts alkylation process. HCP-A and HCP-B were cross-linked phosphazene-based microporous hybrid organic–inorganic polymers. HCP-A and HCP-B were produced in two stages. Hexachlorocyclotriphosphazene reacts with 1-napthylamine to form naphthyl amino phosphazene, which is cross-linked under optimum conditions to make cyclic HCP-A. Phosphorous dichlorophosphazene reacts with 1-naphthylamine to form poly[bis(1-naphthylamino) phosphazene] and is cross-linked to form linear HCP-B. HCP-A and HCP-B porous networks were studied with Brunauer–Emmett–Teller surface areas of 170.89 and 492.03 m2 g−1 and narrow pore sizes of 0.8–1.18 nm. These polymers are promising CO2 adsorbents due to their easy and cost-effective production, thermal stability, surface area, and CO2 absorption capacity.

Serious climate changes and energy-related environmental problems are currently critical issues in the world. In order to reduce carbon emissions and save our environment, renewable energy harvesting technologies will serve as a key solution in the near future. Among them, triboelectric nanogenerators (TENGs), which is one of the most promising mechanical energy harvesters by means of contact electrification phenomenon, are explosively developing due to abundant wasting mechanical energy sources and a number of superior advantages in a wide availability and selection of materials, relatively simple device configurations, and low-cost processing. Significant experimental and theoretical efforts have been achieved toward understanding fundamental behaviors and a wide range of demonstrations since its report in 2012. As a result, considerable technological advancement has been exhibited and it advances the timeline of achievement in the proposed roadmap. Now, the technology has reached the stage of prototype development with verification of performance beyond the lab scale environment toward its commercialization. In this review, distinguished authors in the world worked together to summarize the state of the art in theory, materials, devices, systems, circuits, and applications in TENG fields. The great research achievements of researchers in this field around the world over the past decade are expected to play a major role in coming to fruition of unexpectedly accelerated technological advances over the next decade.