The use of polymer-based nanocomposites (NCs) in which metal and metal oxide nanoparticles are combined represents a critical point of comparison owing to their improved linear optical characteristics and wide indications in optoelectronics, sensors, and medical devices. In this survey, the synthesis method casting, material properties, and optical behavior of polystyrene, polymethyl methacrylate and polyvinyl alcohol–doped NPs have been widely studied, along with many other single and bimetallic-based NCs such as aluminum, silver, and zinc oxide, the latter two of which is also discussed in much detail below. The effects of nanoparticle-specific composition, dose, and preparation on the principal optical properties such as absorbance, reflectance, refractive index, and optical conductivity are identified. The ultraviolet-shielding capacities of the composites have attracted special attention, which can help develop them as protective coatings, packaging materials, and photonic devices as interesting materials. These findings can help to point a way for further experimental development and for applied development of functional NCs.
Currently, the design of efficient multifunctional materials for supercapacitors has become imperative in the field of energy storage and conversion. Porous carbon materials derived from biomass have been widely regarded as the promising electrode materials for supercapacitors. Herein, we have prepared porous carbon materials with Chinese cabbage as the biomass precursor by a facile pyrolysis and potassium hydroxide activation process. Based on the characterisation, Chinese cabbage-derived activated carbon (CAC-3) with a hierarchical micro-/meso-/macroporous structure indicates Brunauer-Emmet-Teller surface area of similar to 953 m2/g and an average pore size of 2.27 nm. CAC-3 indicates outstanding capacitive performance of 760 F/g at 1 A/g and good rate capability as well as superior cycling stability 95.45% of initial specific capacitance after 10 000 cycles. Moreover, the supercapacitor delivers a high specific capacitance of 266.7 F/g at 1 A/g and 78.74% of the capacitance retention at 20 A/g as well as a high energy density of 53.34 Wh/kg at power density of 1200 W/kg. This study provides new insight for the exploration of novel electrode materials with multifunctional structures for green supercapacitor.
Supercapacitors have emerged as promising energy storage devices due to their high power density, rapid charge–discharge capability, and long cycle life. Among various electrode materials, carbon-based materials and metal oxides have gained significant attention for their complementary electrochemical properties. Carbon materials, such as graphene, carbon nanotubes, and activated carbon, provide excellent electrical conductivity, large surface area, and stability, while metal oxides, including manganese dioxide, Co3O4, nickel oxide, and ruthenium oxide, offer high pseudocapacitance through redox reactions. The combination of these materials in hybrid electrode structures enhances energy density, rate capability, and overall electrochemical performance. This review provides a comprehensive analysis of recent advancements in carbon/metal oxide composite electrodes for supercapacitors, focusing on synthesis methods, structural optimization, charge storage mechanisms, and electrochemical performance. In addition, challenges such as material stability, scalability, and cost-effectiveness are discussed, along with potential strategies for future improvements. The integration of nanostructured carbon-metal oxide hybrids presents a viable approach for developing next-generation supercapacitors with enhanced energy storage capabilities for various applications, including portable electronics, electric vehicles, and renewable energy systems.
This study reports the hydrothermal synthesis and structural-optical characterization of tin dioxide (SnO2), zinc oxide (ZnO), graphene oxide (rGO), and their binary and ternary nanohybrids for potential nitrogen dioxide (NO2) gas sensing at room temperature. Four hybrid systems - SnO2-rGO, ZnO-SnO2, ZnO-rGO, and SnO2-ZnO-rGO - were synthesized under optimized hydrothermal conditions and compared with pristine SnO2 nanorods. Field emission scanning electron microscopy analysis revealed nanorod and nanoparticle morphologies anchored on rGO sheets, confirming effective oxide-carbon integration. X-ray diffraction patterns verified the coexistence of tetragonal SnO2 and hexagonal ZnO phases without impurity formation, with crystallite sizes ranging from similar to 4 nm (SnO2) to similar to 48 nm (SnO2-ZnO-rGO). Optical bandgap energies, estimated from Tauc plots, varied between 3.35 eV (ZnO) and 6.00 eV (ZnO-rGO), indicating tunable electronic properties arising from heterojunction coupling and rGO incorporation. The ternary SnO2-ZnO-rGO hybrid exhibited a balanced crystallite size (similar to 48 nm) and stabilized bandgap (similar to 4.20 eV), suggesting improved charge transport and surface reactivity. The results demonstrate that oxide-oxide heterojunction formation combined with a conductive rGO network provides an effective strategy for engineering nanomaterials suitable for room-temperature NO2 sensing.
Efficient utilisation of solar energy is crucial for sustainable power generation, with photoelectrochemical (PEC) water splitting being a promising approach. Cuprous oxide (Cu2O) is particularly attractive to be utilised as photoelectrodes because of their high efficiency and low cost in relation to other materials despite their poor photostability. Therefore, a novel strategy of protected cuprous oxide photocathode with copper (Cu) underlayer and substrate modification was presented in this preliminary study. The fluorine-doped tin oxide (FTO) substrate etching and copper underlayer will enhance the performance of the cuprous oxide photocathode, while the protected nickel oxide (NiO) layer will improve its stability in the electrolyte. The two-level factorial design was utilised to measure and analyse the effects of FTO etching time, copper electrodeposition (ED) voltage, copper and cuprous oxide ED time, cuprous oxide reduction cycle, nickel ED time, and annealing temperature and time on the photocatalytic activity. The morphological, elemental composition and PEC features of the samples are characterised using field emission scanning electron microscopy and a current-voltage monitoring system. Under 100 mW/cm(2) of simulated sunlight, the photoelectrode exhibits a maximum current density of -54.53 & times; 10(-2) mA/cm(2) at 0 V-RHE.
The sol-gel method was used to synthesize Zn1-xBixS compounds (x = 0, 0.25, 0.5, 0.75, and 1) with the aim of studying the structural, morphological, and optical effects of bismuth ions within the crystal lattice of zinc sulfide (ZnS). X-ray diffraction results showed that all samples crystallized in the cubic ZnS phase, with the appearance of a bismuth disulfide secondary phase at higher bismuth (Bi) content. The crystallite size increased from 10.5 nm at x = 0 to 26.7 nm at x = 0.75 and reached 31.6 nm at x = 1, accompanied by a sharp decrease in microstrain from 1.48% to about 0.49%. Field emission scanning electron microscopy images revealed a clear morphological transition from spheroidal ZnS particles to layered, sheet-like particles at higher Bi substitution ratios. Ultraviolet-visible spectrum showed a redshift with a band gap decreasing from 3.95 eV for pure ZnS to 3.59 eV at total substitution (x = 1), attributed to bismuth ions' 6p energy levels near the conduction band edge, creating surface and electron levels that reduce the electron transition energy. These results demonstrate that the sequential replacement of bismuth provides an effective strategy that tailors the structural, morphological, and optical properties of the ZnS compound, making it a promising candidate for thin-film solar cells and photocatalytic applications.
This study shows a green reduction approach for the reduction of graphene oxide (GO) into reduced graphene oxide (rGO) nanosheets using Nicotiana tabacum (tobacco) leaf extract in a wet chemical process at low temperature (70 degrees C). A similar process has been employed to produce ZnO-rGO nanocomposites (NCs). As-synthesized rGO and ZnO-rGO NCs have been investigated with X-ray diffraction, Raman spectroscopy, Fourier-transform infrared spectroscopy, UV-visible spectroscopy, and scanning electron microscopy-energy-dispersive X-ray analysis (SEM-EDX). Raman and EDX tests confirm a considerable reduction of oxygen-containing functional groups from GO in the production of rGO. Furthermore, the produced rGO and ZnO-rGO NCs have been tested as electrode materials for symmetrical supercapacitors (SSCs). The electrochemical performance has been found and obtained high specific capacitance of similar to 207.5 F/g for rGO and 340 F/g for ZnO-rGO NCs at a current density of 2 A/g, respectively. The energy densities of rGO and ZnO-rGO NCs are calculated to be similar to 18.44 and 30.22 Wh/kg, and power densities similar to 1508.72 and 1942.71 W/kg, respectively. Cycling studies at 100 mV/s revealed exceptional retention, with 93.2% capacitance remaining after 2000 cycles for NCs. Thus, the eco-friendly method produced rGO and ZnO-rGO NCs successfully with excellent SSCs electrochemical performance.
In this study, one-dimensional solar cell capacitance simulator simulation was conducted to examine zinc (Zn)-doped copper oxide (CuO) absorbers for photovoltaic applications. Systematically analysed and compared were 6% zinc-doped p-type copper oxide and 12% zinc-doped n-type copper oxide by varying thickness (1.0-2.0 & micro;m), bandgap (1.0-2.0 eV), doping concentration (1010-1020 cm-& sup3;), and temperature (300-350 K). The obtained results showed that 12% zinc-doped n-type copper oxide achieved 25% efficiency at 1.6 & micro;m thickness, 1.65 eV bandgap, and carrier concentration ranging between 1017 and 1018 cm-& sup3;. This configuration also demonstrated thermal stability within the tested temperature range. This confirms that controlled doping concentration critically influences device output and provides reference data for developing copper oxide-based solar cells.
Currently, 7.2 Mt of avocados are produced annually worldwide. It represents between 11% and 16% of the weight of the fruit, is considered a waste, and can be a potential source of starch. This work focused on the elaboration of biofilms using Hass avocado seed starch, its nanoparticles, and a xyloglucan reinforcement in search of an alternative to plastic. The xyloglucan was extracted from tamarind seed, and the nanoparticles were synthesized from the starch using the acid hydrolysis method and ultrasound. Biofilms were developed into four different groups: starch alone (Group 1), starch + nanoparticles (Group 2), starch + xyloglucan (Group 3), and starch + xyloglucan + nanoparticles (Group 4). In each group three different concentrations were used. The biofilms were characterized according to thickness, water solubility, water vapor permeability, degradability, and mechanical properties (tensile strength, elongation at break, and elastic modulus). Strength and permeability improved 2.3 times and 35.02% with the inclusion of 1% nanoparticles and 2.2 times and 28.11% with 8% xyloglucan, respectively. Avocado seed has great potential as a source of starch and as a use for the synthesis of biopolymers that can eventually be taken to the industrial field.
With the modern technological progressions, efficient management and proper utilization of energy resources in transmission and distribution system has become a momentous issue. In addition, power system is undergoing on account of unafforded power generation and distribution in smart grid which effect on energy trading platform that lead to unprofitably for energy producer and increase power loss. However, this paper proposes a virtual power plant (VPP) with the real-time demand response intellectual decision making pricing strategy for the energy bidding difficult by participating in electricity market. The main objective of this research is to develop an optimum energy regulation approach as well as its pricing strategy by considering uncertainness of renewable generations, and unpredictable load demand for future energies management request. The proposed VPP consists of solar energy, wind energy sources which effectively manage generated energy by considering uncertain load demand. For this study, fuzzy logic controller is considered to interconnect among them. The fuzzy rules are developed by using the human thinking so that it can tackle for any complex circumstances for any time of the day. Simulation results for dissimilar conditions of the diurnal are exposed in where fuzzy rules are occupied properly.
Ca aluminate/lanthanide metal fluoride nanocomposites were prepared via a simple photodeposition method. The nanocomposites are composed of orthorhombic Ca5Al6O14 and orthorhombic DyF3 (ErF3) phases with polycrystalline structure. Nanoflakes and irregular nanoscale particles coexist in the nanocomposites. The absorption edge of the Ca aluminate/lanthanide metal fluoride nanocomposites shifts to longer wavelength and the band gap is narrowed. The charge carrier separation efficiency of the nanocomposites is obviously improved which is beneficial for enhancing the photocatalytic activity. Nanocomposites with the ErF3 content of 0.2 mmol exhibit the highest catalytic activity toward crystal violet (CV). The enhanced photocatalytic activity of the nanocomposites for CV degradation is due to increased light absorption ability, reduced band gap, suppressed recombination of electron–hole pairs during the CV photodegradation.
This paper investigates the influence of annealing temperatures on the properties of copper-zinc-tin sulfide (CZTS) thin films synthesized using a low-cost sol-gel spin-coating technique. The thin films were annealed at different temperatures: 340°C, 360°C, 380°C, and 400°C. Analysis of the X-ray diffraction data revealed a consistent kesterite structure in all thin films, with a preferred orientation along the (112) plane. Raman’s spectra confirmed the purity of the phase and confirmed the presence of the CZTS kesterite structure. The morphological and elemental compositions of the thin films showed significant fluctuations in response to changes in annealing temperature. This effect is due to the influence of temperature on the reaction dynamics during the preparation of the deposition solution. The optical properties showed a robust absorption coefficient (>104 cm−1) with optical bandgaps ranging from 1.38 to 1.72 eV. In particular, the CZTS sample annealed at 340°C showed superior crystallinity and outperformed others in optical and electrical properties. To expand the practical implications, the parameters derived from this study were theoretically integrated into a solar cell model (CZTS/(CdS or ZnS)/ZnO:i). Using SCAPS-1D simulation, efficiencies of 11.40% and 10.55% were predicted for the CdS and ZnS buffer layers, respectively. These results provide valuable information for optimizing CZTS thin films to improve solar cell performance.
Sodium-ion batteries (SIBs) have emerged as the most promising secondary battery technology to replace lithium-ion batteries in large-scale energy storage applications. Layered oxides, as important cathode materials for SIBs, face primary challenges in improving cycling stability and enhancing energy density. P2-type Na0.6Mn0.62Ni0.22Fe0.16O2 cathode material boasts a high specific capacity but undergoes phase transitions at high voltage, resulting in poor cycling stability. X-ray diffraction refinement demonstrates that an appropriate addition of fluoride (F−) increases the interlayer spacing of sodium, thereby accelerating sodium-ion diffusion rates. Charge density distribution and electronic state density calculations indicate that F- doping enhances the interactions between Mn and O, as well as Ni and O, thereby inhibiting the dissolution of Mn3+ and Ni3+ and contributing to structural stability. The optimized Na0.6Mn0.62Ni0.22Fe0.16O1.95F0.05 can deliver a high capacity of 138.8 mAh g−1 at a 2 C rate and retain a capacity of 80 mAh g−1 after 100 cycles, demonstrating significantly improved cycling stability. This work achieves an increase in specific capacity cycling stability by regulating the activity and stability of transition metals through F− substitution, providing a new strategy for regulating the chemical environment of Na-Mn-Ni-Fe-O cathodes.
The growing presence of pharmaceutical pollutants such as naproxen in aquatic systems poses major challenges to conventional water treatment. Cerium oxide nanorods (CeO2 NRs), known for their cost-effectiveness, high redox potential, and environmental compatibility, offer a promising solution for sustainable remediation. In this study, cerium dioxide NRs were synthesized via a hydrothermal method at controlled temperatures ranging from 363 to 423 K. X-ray diffraction confirmed the formation of a face-centered cubic fluorite phase, with crystallite sizes decreasing from 21.514 to 6.237 nm as synthesis temperature increased. Field-emission scanning electron microscopy revealed a temperature-driven morphological transformation from elongated to cuboidal rods, with length reduction from 206 to 94.9 nm. Fourier transform infrared spectroscopy identified characteristic Ce–O and Ce–O–Ce vibrations, with higher temperatures yielding enhanced crystallinity and reduced surface adsorbates, improving photocatalytic performance. Ultraviolet–visible spectroscopy showed a bandgap reduction from 3.74 to 3.21 eV. The optimally synthesized nanorods achieved 59% naproxen removal under xenon lamp irradiation (λ > 300 nm, 300 W) and 71.01% degradation under blue laser light (λ = 450 nm, 100 mW) within 150 min. These findings demonstrate a practical and scalable approach for rapid pharmaceutical pollutant removal and sustainable water treatment.
The energy generation from biomass wastes necessitates understanding the kinetics and mechanisms of thermal decomposition to optimize reactor design and efficiency. However, the decomposition of biomass, which comprises hemicellulose, cellulose, and lignin, poses analytical challenges. This study focuses on the thermal decomposition of sugarcane bagasse, a common biomass used for energy co-generation. Thermal analysis performed using thermogravimetric/differential thermal analysis in an argon atmosphere at varying heating rates (2, 5, and 30 K/min) revealed key insights into its decomposition mechanisms. The overall reaction exhibited three distinct peaks in the derivative thermogravimetry (DTG) curve, corresponding to the decomposition of hemicellulose, cellulose, and lignin. Gaussian deconvolution was employed to separate these peaks, followed by analysis using various nonisothermal kinetic methods. Integral methods revealed two decomposition stages but presented challenges in selecting precise reaction models. These challenges were mitigated by separating the reactions into their components. The reaction order model f(alpha) = (1 - alpha)(1.5) effectively described the decomposition kinetics. Activation energy values ranged from 120 to 280 kJ/mol for the overall reaction, with specific values of 200-280 kJ/mol for hemicellulose, 280-350 kJ/mol for cellulose, and 40-150 kJ/mol for lignin. Nonlinear least square minimization refined these values, showing better fitting in reconstructed d alpha/dT plots.
Lanthanum strontium cobaltite (La1-xSrxCoO3) thin films with 0.1, 0.2, 0.3, and 0.4 mol % strontium were synthesized by spray pyrolysis technique. These thin films were sintered at 1100°C and studied by XRD for confirmation of phase and to find the crystalline size. Field effect scanning electron microscopy surface morphological analysis was done and found to be spherical in shape and spongy. Elemental analyses were done by energy-dispersive atomic X-ray spectroscopy and no phase changes after sintering. Atomic force microscopy studied the morphological structure and it was found that uniformity and roughness increased, the grain size decreased, and the film became more porous. The dielectric constant was measured with a variation of temperature, and it exhibited semiconducting behavior.
The significant advancement in the field of energy-harvesting techniques in the last decades makes it a possible alternative to provide a continuous power supply for low-power electronic devices exclusively for implanted biomedical devices. This makes it a most promising and widespread research topic. This paper presents a comprehensive review of the different methods of improving the performance of piezoelectric energy harvesters (PZEH). This includes the different key aspects, such as the basic fundamentals of the piezoelectric mechanism and performance-enhancing techniques, such as structural modification, broadband techniques, and the application of PZEH in the field of biomedical devices.
In this study, the plastic viscosity and yield stress of cement-based grouts containing n-ZnO nanoparticle added fly ash have been experimentally investigated. The fly ash ratios of the prepared grouts are 5%, 10%, 15%, 20%, 25%, and 30% by mass. The n-ZnO nanoparticles ratios in each fly ash concentration are 0.3%, 0.6%, 0.9%, 1.2%, and 1.5%. In this study, w/b ratio was selected as 1.0 because of that observing the effects of higher w/b ratios on the rheological properties of grout mixes. Ultrasonication method was applied to minimize n-ZnO precipitation in free water and to provide homogeneous dispersion in water by removing these adhering nano powders from each other. Test results showed that as the dilatant (shear-thickening) behavior was observed in all grout samples prepared for this study, modified Bingham analytical model was used to describe the rheological properties and flow behavior of the grout samples prepared for this study. n-ZnO appears to have a significant effect on regulating the amount of water required for cement-based grouts. The substitution of fly ash together with n-ZnO in grout mixtures causes the plastic viscosity values of the samples to decrease. The exponential increase is observed for the yield stress of the grout mixtures with respect to the increase in the n-ZnO additive ratio. Moreover, the increase in the fly ash amount in all n-ZnO additives causes the yield stress values of the mixtures to decrease. In addition to all, the developed artificial neural network model can predict the plastic viscosity and yield stress values of cement-based grouts containing n-ZnO nanoparticle added fly ash with average error rates of −0.52% and −0.31%, respectively.
Agriculture residue management has gained popularity in recent years due to the emphasis on sustainability. After harvesting, large amounts of waste are produced, which is often dumped into the environment, leading to pollution. These wastes can also be utilized in the concrete industry to help reduce the depletion of mineral resources, contributing to long-term sustainable development. Experimental tests were conducted to evaluate the effect of horse gram pod ash (HGA) as a partial replacement for cement in concrete. The results showed that the compressive strength of mixes with HGA replacement increased by 4–8%. However, the strength decreased when HGA content exceeded 8%. Despite this, the split tensile strength of the HGA8 concrete was 10.52% higher than that of the control concrete, with 8% HGA showing superior strength compared to other replacement levels. A 26.15% increase in flexural strength was observed in concrete with 8% HGA content compared to control concrete. Durability tests, including absorption, sorptivity, rapid chloride penetration, and acid resistance, indicated that the durability properties of HGA concrete mixes are comparable to conventional concrete. The study suggests that HGA has significant potential as an agricultural waste material in green concrete due to its beneficial properties and contribution to waste management.
This review article explores the interface between thermodynamics and nanotechnology, paying special attention to the unique difficulties and possibilities of working at the nanoscale. Using basic ideas from quantum physics and statistical mechanics, it shows how thermodynamics is crucial for understanding how nanoscale systems behave. In the context of small-particle ensembles, where quantum effects significantly impact energy landscapes, the use of statistical thermodynamics becomes crucial. The equilibrium conditions are controlled by surface energy, capillarity, and wetting events, and the research delves into the thermodynamics of nanoscale interfaces. The revolutionary power of nanotechnology is highlighted in the field of energy conversion, namely in thermoelectric nanomaterials and nanoscale photovoltaics. More specifically, the study aims to provide light on the complex interactions among phonons by investigating thermal processes at the nanoscale. It highlights the importance of thermodynamics in developing methods for controlling heat on such a microscopic scale. The study also delves into nanomaterials' inherent thermodynamic tendency for organisation, illuminating how they self-assemble according to molecular thermodynamics. In order to tackle the ever-changing field of nanotechnology, which presents problems to traditional thermodynamic models, the article stresses the need of creative methods and multidisciplinary collaboration. Safety and environmental impact are integrated into the inquiry process to guarantee that it is in line with sustainability standards. In the end, the study shows how thermodynamics and nanotechnology work hand in hand, describing all the complex phenomena that need to be studied together in order for society to reap the advantages of both fields to the fullest.
