Synthesis Of Nickel Oxide Research Articles

Synthesis of NiO: BaO nano structure by chemical method with Antibacterial activity to Escherichia coli, Klebsiella spp., Staphylococcus aureus, Staphylococcus epedermidis andcandida spp

Nanostructured materials have garnered significant attention due to their remarkable chemical and physical characteristics. Because of their exceptional qualities and potential uses in technology. Nanostructured transition metal oxides are one of the many nanomaterials that need particular attention. The goal of this study was to synthesize nickel oxide and barium oxide nanostructures by the reaction of Nano powders: nickel sulphate NiSO4, barium chloride BaCl3, and molten sodium hydroxide, potassium hydroxide (NaOH: KOH) and examine their physical and biological properties. According to the results of UV–Vis, the gap band of the nanostructure was calculated with a range of 3.6–3.27 eV. Scanning Electron Microscopy (SEM) pictures appear to create aggregated nanoparticles with particle size of 29 nm according to Transmission electron microscopy (TEM) with a spherical shape. This results proved that NiO: Ba nanostructure an efficient and stable. It was observed that the diameter of the inhibition zone bacteria include E. coli and Klebsiella spp. (21,18) mm while inhibition zone of bacteria S. aureus,S. epidermidisgram positive bacteria and yeast candida spp.(19,19 and 21)mm. As can be shown, the antibacterial activity of the (NiO: BaO), nanostructure increases with decreasing concentration and is more effective against E. coli gram-negative than it is against S. aureus and S. epedermidis gram-positive. This finding might be explained by the fact that, due to differences in their cell wall composition, gram-negative bacteria are more vulnerable to antibacterial medications than gram-positive ones. The synthesized NiO: Ba nanostructures had the potential for higher inhibition and killing of gram-negative than gram-positive bacteria.

Enhancing energy storage with binder-free nickel oxide cathodes in flexible hybrid asymmetric solid-state supercapacitors

The need for flexible electrode materials for the development of flexible supercapacitors has drawn scientific interest recently. We present the successful synthesis of nickel oxide thin films using the successive ionic layer adsorption and reaction (SILAR) method, with the use of three different cationic precursors. This paper provides comprehensive details on the synthesized nickel oxide structure, morphology, and elemental analysis in addition to its electrochemical characteristics, which include specific capacitance (SCs), charge transfer resistance, etc. The produced nickel oxide electrodes achieved specific capacity as 120 C g−1, 517 C g−1, and 1147 C g−1 with different nickel precursors such as nickel chloride, nickel nitrate, and nickel sulfate respectively, at a 1 mA cm−2 current density. A flexible hybrid asymmetric solid-state supercapacitor (FHASS) (S:NiO//PVA-KOH//CuS) device delivered SCs of 165 Fg−1 at a 0.5 mA cm−2 current density, with a maximum SE of 58.87 Wh kg−1 at SP 347 W kg−1. FHASS device exhibits capacitive retention and coulombic efficiency of between 79 % and 96 % after 5000 successful GCD cycles. Also, the device retained an outstanding 97 % of its capacitance at a 175º bending angle. Furthermore, to illustrate its real-world applicability, the constructed device underwent 30 s of charging to a lightning LED table lamp for 90 s. The fabricated device is bringing a new era of broad integration of device-grade applications.

Photocatalytic performance of pristine NiO and Ni6MnO8 nanopowders in degradation of Rose Bengal dye.

Effective tuning of bandgap of transition metal oxides is a promising approach in improving their photocatalytic activity towards organic pollutant removal from water. The present paper describes synthesis of nickel oxide and Ni6MnO8 nanopowders by simple hydrothermal technique. During the synthesis of nickel oxide by hydrothermal process, addition of Mn source resulted in the formation of Ni6MnO8. X-ray diffraction analysis has confirmed the formation of nickel oxide and Ni6MnO8 both having cubic structures. The average crystallite size decreases from 20 to 12nm on increasing Mn source concentration during the synthesis of nickel oxide. Rectangular, hexagonal, and triangular faceted structures are revealed from the scanning electron microscopic images. HRTEM also indicated formation of cubical shaped structure with average sizes of 32 and 21nm for pristine NiO and Ni6MnO8 nanopowders. In the case of Ni6MnO8 nanopowder, inter-connected cubes are seen. Modification in Ni6MnO8 nanopowder is found to display multiple optical band gaps at 1.21, 1.82, and 2.65eV. The formation of Ni6MnO8 phase was further confirmed by XPS studies due to the presence of + 4 oxidation state of Mn. The photocatalytic properties of synthesized nickel oxide and Ni6MnO8 nanopowders are measured by using Rose Bengal dye under UV illumination. Enhancement in the photocatalytic activity is noticed in the case of Ni6MnO8 nanopowder as compared to nickel oxide nanopowder. Nearly 90% dye degradation is observed on utilizing Ni6MnO8 nanopowder.

Green engineering of NiO nanoparticles decorated with Arachis hypogaea shell extract for biomedical applications

Abstract We attempted to synthesize nickel oxide nanoparticles (NiO-NPs) utilizing waste Arachis hypogaea (peanut) shell extract and studied their structural, morphological, and biological performance for biomedical applications. The green engineered NiO-NPs possessed a face-centered cubic structure with an average particle size of 20 nm in highly crystalline form. NiO-NPs were shown to have an optical resonance peak at 327 nm with 3 eV as the optical band gap according to the UV–visible spectra, and the stretching band between Ni–O were evidenced from the FTIR and Raman spectrum. Utilizing green approach the stable nanoparticles were obtained with average particle size of 31 nm from SEM analysis; zeta potential value of −17.6 mV, and PDI as 0.68, revealed the formation of spherical nanoparticles with distinct morphologies without aggregation. XPS analysis confirmed the oxidation states of the elements Ni (2p) and O (1s). This approach may help to increase the surface area, increasing the possibility of nanoparticles interacting with bacterial cells. Furthermore, the presence of nickel and the oxygen oxidation state were confirmed by XPS. Proteus vulgaris, Streptococcus oralis, Bacillus subtilis, and Escherichia coli were found to be susceptible to the antibacterial action of the produced NiO-NPs, with a maximal zone of inhibition of 10.25 mm at 500 μg/ml for P. vulgaris. For P. vulgaris and E. coli, the minimum inhibitory concentrations of NiO were 5.36 and 12.55 %, respectively, at 31.25 μg mL−1. We hereby claim that green engineered NiO NPs decorated with A. hypogaea shell extract have great potential for pharmaceutical and biomedical applications.

Chemical synthesis of NiO nanoparticles from Solanum trilobatum leaf extract for antibacterial and cytotoxic properties

The chemical precipitation approach was employed to synthesize Nickel oxide nanoparticles (NiONPs) using Solanum trilobatum leaf extract as the stimulant and Nickel nitrate as the precursor. The Nickel oxide is examined using a range of characterization methods including X-ray diffraction, Fourier Transform Infrared spectroscopy, High-Resolution Transmission Electron Microscopy, High-Resolution Scanning Electron Microscopy, X-ray photoelectron spectroscopy, Thermo gravimetric Analysis/Derivative Thermo gravimetric Analysis, Diffuse Reflectance Spectroscopy, cytotoxicity and antimicrobial investigations The X-ray diffraction examination determined that the average size of the crystals increases as the quantities of leaf extract in the NiO2 composites rise. The decrease in line broadening (β) value and the increase in leaf extract concentrations may be the cause of this phenomenon. The FTIR spectrum confirms that the as-synthesized NiO-NPs are of great purity and match well with the XRD pattern. The thermal stability of the synthesized samples was determined using TGA/DTG analysis. The analysis was conducted in an air atmosphere, with the temperature increasing at a rate of 10°C per minute. The temperature range for the analysis was from room temperature to 750°C. The optical properties are determined by the use of Diffuse Reflectance Spectroscopy, which examines the coordinated movement of electrons in the conduction band when exposed to electromagnetic waves. Rat skeletal muscle cell line and SKMEL cancer cells were cultured on 96-well plates and incubated at 37°C and 5 % CO2 for 24 hours to allow them to adapt to the culture conditions. An investigation was conducted to assess the antibacterial properties of synthesized nanocomposites against two types of bacteria: gram-positive Staphylococcus aureus (MTCC No: 87) and gram-negative Escherichia coli (MTCC No: 443), in order to explore their potential for biological applications.

Direct synthesis of nickel oxide nanoparticles from pregnant leach solution by using electrodeionization and Fenton processes in the presence of EDTA

This paper presents the results of a novel study on the direct synthesis of nickel oxide nanoparticles from a synthetic pregnant leach solution (PLS) as a middle stage product of hydrometallurgy process of nickel production. To increase the nickel proportion in the initial PLS, electrodeionization was utilized in the presence of EDTA to form an anionic complex ([Ni-EDTA]2−) with Ni2+ cations, allowing their separation from cobalt cations through the EDI process. Subsequently, the Fenton process was applied to synthesize nickel oxide nanoparticles from the complex containing solution. The proposed hybrid process was conducted in two different modes of one-stage and two-stage EDI process followed by the Fenton process. Different analysis methods including AAS, XRD, FE-SEM, and ICP were used for qualitative and quantitative evaluations. The analyses’ results revealed that by implementing one-stage EDI process followed by Fenton process resulted in producing nickel oxide nanoparticles with an average particle size of 45 nm and purity of about 98 %. Also, it was seen that about 81 % of initial nickel content of the initial PLS was recovered as nickel oxide nanoparticles. In the case of two-stage EDI process, 100 % pure nickel oxide nanoparticles with average size of 55 nm and recovery of 65 % was produced. The results showed that the innovative hybrid EDI/Fenton process can be considered as a promising approach for direct synthesis of high purity nickel oxide nanoparticles from PLS. However, it should be noted that there was a trade-off between purity of nickel oxide and nickel recovery from PLS.

Bioengineered Nickel Oxide Nanofabrication for Energy Storage Systems, Degradation of Refractory Water Toxicity, and Antibacterial Study

AbstractNickel oxide (NiO) nanoparticles were synthesized using a green method involving Pterolobium hexapetalum flower extract as the reducing agent. Synthesized nickel oxide nanoparticles (NiO NPs) were thoroughly characterized using X‐ray diffraction, UV–vis spectroscopy, Fourier‐transform infrared spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM), and Brunauer–Emmett–Teller (BET) surface area analysis. The XRD analysis confirmed the pure formation of NiO NPs. TEM and SEM images revealed the size, shape, and surface morphology of the nanoparticles. BET analysis indicated a high surface area, making these nanoparticles suitable for various applications. The NiO NPs were further investigated for their potential in supercapacitor applications, demonstrating excellent electrochemical performance. NiO@rGO electrode with graphene proportion showed a maximum specific capacity of 1266 Fg−1 at 1 Ag−1. Moreover, following the 3000‐cycle assessment, the specific retention of 98.2% confirmed that the electrode had high cyclic stability. Additionally, their effectiveness in dye degradation was evaluated, showing promising results in removing organic dyes from wastewater. The antibacterial activity of the NiO nanoparticles was also assessed, indicating significant inhibition against various bacterial strains. These multifaceted studies suggest that NiO NPs synthesized from plant extract hold great promise for applications in energy storage, environmental remediation, and antimicrobial treatments.

Calcined Nickel Oxide Nanostructures at Different Temperatures Onto Graphite for Efficient Electro‐Oxidation of Ethylene Glycol in Basic Electrolyte

ABSTRACTFabricating a highly active and stable nanocatalyst material displays a great concern when constructing a commercially viable ethylene glycol (EG) fuel cell. Herein, nickel oxide nanostructures were grown onto graphite (NO/T) using coprecipitation and calcination protocol at different temperatures. Techniques for XRD, TEM, SEM, and EDX investigations were used to look into the produced crystal planes, shape, and elemental mapping of synthesized nickel oxide nanoparticles. Different NO/T nanocatalyst electroactivities were examined in order to oxidize EG molecules in basic electrolyte. The surface area values of calcined nanostructures at 200°C and 300°C were much higher than those measured at NO/T‐400 by 7.62 and 3.71 folds to explain their outstanding performance. Some kinetic information for varied NO/T nanocatalysts was derived including the electron transfer coefficient, rate constant, and surface coverage values. Electron transfer rate constants of 0.1946, 0.3734, 0.0113, and 0.0303 s−1 were calculated at NO/T‐200, NO/T‐300, NO/T‐400, and NO/T‐500, respectively. Increased oxidation current densities could be achieved when NO/T nanomaterials were subjected to lowered calcination temperatures. NO/T‐200 and NO/T‐300 nanocatalysts also displayed decreased Eonset for alcohol oxidation process by 20 and 41 mV in relation to that at NO/T‐400. Moreover, chronoamperometric experiments revealed the prevalence of the stable behavior during EG oxidation at these nanostructures, especially for calcined ones at 200°C and 300°C. Much reduced poisoning rates were measured at NO/T‐200 (0.171 s−1) and NO/T‐300 (0.067 s−1) when contrasted to that at NO/T‐500 (0.727 s−1). Increasing the alcohol and supporting electrolyte concentrations was beneficial in improving the charge transfer characteristics of NO/T nanocatalysts as demonstrated by EIS measurements. This study supports the promising activity of NiO nanoparticles onto graphite as anode materials for direct alcohol fuel cells.

Green synthesis of undoped and Ag-doped NiO nanoparticles: Evaluation and their synergetic effect on antimicrobial, anticancer, and antioxidant activities

In this investigation, we successfully synthesized nickel oxide nanoparticles (NiO NPs) using a combustion method with Acacia nilotica gum as a biofuel, and systematically altered silver (Ag) concentrations within the NiO matrix. Post-calcination at 400 °C, various characterization techniques confirmed the formation, surface morphology, and crystalline characteristics of NiO NPs. The Ag-doped NiO NPs, particularly the NiAg4 sample, demonstrated remarkable antimicrobial efficacy, with superior activity against both fungal and bacterial pathogens. The NiAg4 sample also exhibited potent cytotoxicity against HT-29 human colon cancer cells, achieving an IC50 value of 1.5 mg/mL. Toxicological assessments revealed that both undoped and Ag-doped NiO NPs maintained biocompatibility with human red blood cells, indicating their potential for biomedical applications. Additionally, the NPs showed strong antioxidant activity and protein kinase inhibition, further supporting their therapeutic potential. These findings suggest that Ag-doped NiO NPs synthesized through a green protocol possess enhanced bioactivities, making them promising candidates for future in vivo studies and diverse biomedical applications.

Tailoring photocatalytic performance: Lanthanum doping in nickel oxide for efficient degradation of some industrial cationic dyes in visible light radiation

Metal oxide nanoparticles have emerged as an important component in heterogeneous photocatalysis, which uses light-induced reactions on the surface of a catalyst to drive chemical transformations. The improved photocatalytic activity of lanthanum-doped metal oxide nanoparticles has been the subject of research due to their special qualities, which include enhanced photocatalytic performance, stability and absorption of visible light. This study involves co-precipitation approach to synthesize nickel oxide nanoparticles and nickel oxide nanoparticles doped with lanthanum. The nanoparticles were determined using UV-Visible absorption spectrophotometry, X-ray diffraction spectroscopy, Energy-disperse spectroscopy, Photoluminescence spectroscopy and Field emission scanning electron microscopy. For the photodegradation of malachite green and rhodamine B dyes, synthesized nanoparticles were employed as photocatalysts. Compared to pure NiO, the photochemical activity of 4 % Lanthanum-doped NiO was higher. The degrading efficiency of 4 % La-doped NiO is 89 % effective towards rhodamine B and 87 % for malachite green. In addition, entrapment was done to identify primary active species responsible for photocatalytic activity. The present study likely provides new insights and novelty into the photocatalytic mechanisms at play, including how lanthanum doping affects the generation and dynamics of reactive oxygen species (ROS) like hydroxyl radicals and superoxide anions, which are responsible for the breakdown of dye molecules.

Harnessing hyperaccumulator (Brassica oleracea var. alboglabra) extract for green synthesis of nickel oxide nanoparticles: A prospective route for post-phytoremediation

Even though phytoremediation is considered a green technology for remediating heavy metals, there are some problems with the application of this technology, particularly when it comes to managing the biomass that is used. So, processing biomass needs to be given a lot of attention. This study outlined the utilization of extracts obtained from the hyperaccumulator plant Brassica oleracea var. alboglabra to synthesize nickel oxide nanoparticles. Subsequently, the nanoparticle underwent testing to determine its suitability as an absorbent for heavy metals, specifically lead, as well as its efficacy as an antifungal agent against Fusarium sp. strain. The characterization of nickel oxide nanoparticles involved several measurements, such as scanning electron microscopy analysis, high- and low-resolution transmission electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and hysteresis curve acquisition. The research findings indicate that the extract from hyperaccumulators can be utilized for the synthesis of NiO, which exhibits an absorption capacity exceeding 98% and serves as an efficient antifungal agent against Fusarium sp. pathogens. The approach utilized in this study not only prioritizes "green" and sustainability factors but also takes into account the economic aspects associated with the items being manufactured. The research has important implications in two areas. Firstly, it demonstrates the utilization of natural resources (B. oleracea var. alboglabra) in the production of nickel oxide, which serves as a safer and more eco-friendly substitute for dangerous chemicals. Furthermore, it aids in the advancement of novel techniques for effectively managing biomass hyperaccumulators.

Thermodynamic and exhaust emission studies of CI engine powered by neem oil methyl ester blends doped with nickel oxide nano additives

AbstractAssessment of alternate fuel is categorized on thermophysical aspects and performance—emission derived due to its combustion. Data derived from such analysis is short as the energy expenditure to available chemical exergy of fuel is rarely studied. The study of energy derived from fuel energy gives a detailed picture of fuel efficiency and broadens the field of fuel search criteria. The current article aims to find the thermodynamic effects in terms of energy and exergy utilization of neem biodiesel blends and nickel oxide nano additive dosed neem biodiesel blends. Neem biodiesel was transesterified using standard procedures and analyzed using gas chromatography and mass spectroscopy. Later, neem biodiesel was blended with diesel in three volumetric proportions, that is, NB25, NB50, NB75, and pure Neem Oil Methyl ester was investigated as an engine fuel, and later synthesized nickel oxide nano additives of 25 mg/L was added to all the above fuels and further studied for energy, exergy utilization on a TV‐1 VCR engine test rig under varying engine CR. Nickel oxide additives were manufactured using homogenous addition method and were thoroughly studied for formation and presence of constituents using XRD, FE‐SEM, and EDS methods. The usage of nano additives does prove reduction in exergy destruction and entropy generation for NB25 base blend with 25 mg/L NiO leading to a reduction of 8.2% and 9.7% when compared to base blends. Also, the emission found for hydrocarbon, and carbon monoxide for all base fuel blends reduced by an average of 16.8% and 7.35%.

Steering elementary steps towards advanced alkaline hydrogen evolution via a sweet marriage of O-defected NiO and Cu

Water adsorption/dissociation and hydrogen intermediates (H*) desorption are the two elementary steps for hydrogen evolution reaction (HER) kinetics. This study builds on the promising concept of planning each step simultaneously to optimize in a whole. Theoretical and experimental approaches are combined to design and synthesize nickel oxide with moderate oxygen vacancy (VO) coating copper nanowires, namely m-VO NiO/Cu, for excellent HER in alkali. The construction of VO expedites H2O adsorption and dissociation on NiO, thereby significantly increases H* coverage on the surface. Subsequently, the incorporation of Cu creates accessible H* adsorption sites by limited hydrogen spillover from NiO to Cu, thereby facilitates the desorption of the next hydrogen directly on NiO continuously. The sweet marriage of VO NiO and Cu endows the most promising alkaline HER performance of a 20 mV overpotential at 10 mA cm–2 with a Tafel slope of 39.9 mV dec–1. This work presents a fresh perspective on upgrading multi-step reaction kinetics and encourages further research on advanced earth-abundant catalysts.

Synthesis of Silver Nanoparticles by Solanum trilobatum L. Aqueous Extract and Their Antibacterial Activity

ABSTRACT Solanum trilobatum L. (Solanaceae), commonly known as nightshade, has been traditionally used by various populations to treat a variety of ailments. Environment-friendly alternatives to chemical and physical procedures for the synthesis of nanomaterials have been proposed. In this research, the hot plate combustion method is used to synthesize nickel oxide nanoparticles (AgNPs) from silver nitrate and S. trilobatum leaf extract. According to X-ray diffraction (XRD) tests, the cubic phase was face-centered, had good crystallinity, and had average crystallite sizes. According to morphological studies, the surface has a cylindrical and rod-like morphology, and average particle size estimates from UV-visible spectroscopy (UV), Fourier transform infrared (FT-IR), concur well with XRD, and the bio-reduced silver nanoparticles were characterized. Staphylococcus aureus, Enterococcus faecalis, Streptococcus mutans, Pseudomonas aeruginosa, and the human pathogenic microorganisms were used to investigate the antibacterial efficacy (12.5, 25, 50 μg/mL) of these biologically created silver nanoparticles.

Comparison activity of pure and chromium-doped nickel oxide nanoparticles for the selective removal of dyes from water

The current study involves a synthesis of a composite of nickel oxide nanoparticles (NiONPs) with a chromium dopant to yield (Cr/NiONPs). Synthesis of nickel oxide was performed by the co-precipitation method. The synthesis of the composite was conducted by the impregnation method. FTIR, EDX, SEM, and XRD were used to characterize the synthesized materials. The synthesised materials’ point zero charges (PZC) were performed using the potentiometric titration method. The obtained results show that the PZC for neat nickel oxide was around 5, and it was around 8 for Cr/NiONPs. The adsorption action of the prepared materials was examined by applying them to remove Reactive Red 2 (RR2) and Crystal Violate (CV) dyes from solutions. The outcomes demonstrated that Cr/NiONPs were stronger in the removal of dyes than NiONPs. Cr/NiONPs achieved 99.9% removal of dyes after 1 h. Adsorption isotherms involving Freundlich and Langmuir adsorption isotherms were also conducted, and the outcomes indicated that the most accurate representation of the adsorption data was offered by Langmuir adsorption isotherms. Additionally, it was discovered that the adsorption characteristics of the NiONPs and Cr/NiONPs correspond well with the pseudo-second-order kinetic model. Each of the NiONPs and Cr/NiONPs was reused five times, and the results display that the effectiveness of the removal of RR2 dye slightly declined with the increase in reuse cycles; it lost only 5% of its original efficiency after the 5 cycles. Generally, Cr/NiONPs showed better reusability than NiONPs under the same conditions.

Biocidal activities of nickel oxide nanoparticles modified by copper and manganese, synthesized by green process

In recent years, the development of dual dopant‐based nanoparticles (NPs) has gained significant attention as they possess exceptional physico‐chemical and biomedical properties, making them potential candidates for antimicrobial and anticancer uses. In this research, we successfully synthesized nickel oxide (NiO) and copper, manganese‐doped NiO (CuMn:NiO) NPs using a green synthesis method. The synthesis process involved Trigonella foenum‐graecum (T.f.graecum) leaves extract as a nucleating agent. The synthesized nanoparticles were confirmed by various physico‐chemical studies. Based on X‐ray diffraction analysis, the median size was determined as 36 nm for NiO and 32 nm for CuMn:NiO NPs. The antibacterial study revealed that CuMn:NiO NPs exhibited a higher zone of inhibition in contrast to both Gram‐positive (Streptococcus pneumoniae, Bacillus subtilis, Bacillus megaterium) and Gram‐negative bacteria (Klebsiella pneumoniae, Escherichia coli, Vibrio cholerae) compared with NiO NPs and commercial amoxicillin. The antifungal studies conducted against Candida albicans demonstrated that CuMn:NiO NPs exhibited enhanced efficacy in comparison to NiO NPs. In vitro testing against human breast cancer cells (MCF‐7) demonstrated the anticancer potential of NiO and CuMn:NiO NPs, supported by IC50 concentrations of 11 and 9 μg/mL, respectively. The photoluminescence (PL) spectra of NiO and CuMn:NiO NPs exhibited a green emission at 508 and 518 nm, respectively, which indicated the generation of active free radicals by the NPs. These findings suggest that CuMn:NiO NPs hold promise in the healthcare industry.

Assessment of Ailanthus altissima seed oil as a potential source for biodiesel production using nickel oxide nanoparticles catalyst

The identification of suitable non-edible plant feedstock is crucial not only to meet energy demands but also to be environmentally friendly. This study aimed to synthesize nickel oxide (NiO) nanoparticles and use these for synthesizing biodiesel from the non-edible feedstock Ailanthus altissima. The confirmation of NiO synthesis and its characteristics were studied using XRD and SEM. The biodiesel synthesis and its physicochemical characteristics were confirmed using GC–MS, NMR, and FT-IR spectroscopies. The fuel characteristics were examined using ASTM standard procedures. The results confirmed that the nanoparticles were crystalline, spherical to cuboidal in shape, and had an average diameter of 24 nm. The suitable set of parameters for the optimum biodiesel yield (95 %) was the oil-to-methanol ratio of 1:24, 25 mg of catalyst, 60 °C temperature, and a reaction time of 90 min. The majority of the fuel's characteristics fell within ASTM D-6751 acceptable ranges. 14 distinct kinds of FAMEs are present, according to the GC–MS results. The FT-IR spectra confirmed the successful synthesis of biodiesel, which displayed significant peaks for several functional groups. 1H NMR and 13C NMR spectrums confirm the conversion of biodiesel synthesis. The environmental friendliness of AAB (Ailanthus altissima biodiesel) and its competitiveness as a feedstock for biodiesel production on a commercial scale are confirmed by its physicochemical properties.

Synthesis of Nickel Oxide / Cerium Dioxide/ Graphene Oxide (NiO/CeO₂/GO) Composite as an Organic Pollutant Remover of Dyes

Before industrial effluents are released into the environment, several techniques have been developed to remove colours from them. These techniques include ion exchange, photocatalytic degradation, chemical oxidation, adsorption, and osmosis. Since these dyes may be totally broken down by photo-catalytically active semiconductors when exposed to light, photocatalysis is one of these approaches that is thought to be environmentally friendly and has been widely employed for environmental cleanup In the current study, a hydrothermal approach was used to create a NiO/CeO₂/GO nanocomposite that was heated for 24 hours at 180 °C using a Teflon liner. To confirm the creation of nanocomposite material, the synthesised nanomaterials were characterised using a variety of spectroscopic methods, including XRD, FTIR, Raman Spectroscopy (RS), SEM, Photo Luminescence Spectra (PL), and Dynamic Light Scattering (DLS). The materials that were synthesised were investigated as photocatalysts for the breakdown of Methylene Blue (MB) dye when exposed to sunlight. The product's photocatalytic activity on methylene blue was examined. It has been demonstrated that adding GO increases absorption while lowering bandgap energy. The elimination effectiveness of methylene blue from an aqueous solution was investigated, and it was found to be 93.22% when the ideal circumstances of NiO/CeO₂/GO of 0.10 mg/L, pH 5, and contact duration of 40 min under visible light were used.

Investigations of charge extraction and trap-assisted recombination in polymer solar cells via hole transport layer doped with NiO nanoparticles

Polymer solar cells (PSCs) are limited in their power conversion efficiency (PCE) by trap-assisted recombination caused by localized deep trap states. Therefore, developing efficient hole transport layers (HTLs) for PSCs is essential for facilitating the hole extraction stage from the photoactive layers. As part of this study, an organic/inorganic hybrid HTL was prepared by mixing synthesized nickel oxide (NiO) nanoparticles (NPs) of average size ranging from 16 to 21 nm with poly(3-hexylthiophene) (P3HT). Based on this hybrid HTL, multilayer PSCs with an ITO/ZnO/P3HT:PC61BM/P3HT:NiO NPs/MoO3/Ag structure were fabricated and characterized. As a result of the incorporation of the optimum ratio of 5 wt% NiO NPs in the P3HT layer, the PCE obtained 3.73% compared to pristine devices (2.70%) fabricated without the P3HT layer. A charge extraction by increasing voltage (CELIV) measurement confirmed enhanced hole extraction at the active layer/HTL interface. The low fluorescence emission of the P3HT/NiO NPs film enabled efficient hole extraction at the active layer/hybrid HTL interface. Adding NiO NPs beyond 5 wt% to the P3HT layer causes deep trap states to form, which facilitated trap-assisted recombination and slowed down the mobility of the holes. Consequently, we can gain insight into how to improve PSC performance with hybrid HTL.

Green synthesis of cotton flower shaped nickel oxide nanoparticles: Anti-bacterial and tribological studies

The goal of this study was to synthesize nickel oxide nanoparticles (NiO-NPs) by the sol–gel method, which involved the use of Cassia Fistula is a herbal and medicinal plant. The Cassia Fistula (CF) plant extract acts as a stabilizing and capping agent. Further, NiO-NPs were characterized using UV–Visible spectroscopy (UV–Vis), Powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM) and Energy Dispersive X-Ray Spectroscopy (EDX). According to the results of UV–Visible, the absorption spectroscopy has displayed that the band gap is 3.5 eV. The biological properties were studied for prepared NiO-NPs. The antibacterial testes were examined using different bacterial strains such as Escherichia coli, Staphylococcus aureus and Staphylococcus Epidermis and dose-dependent inhibition response was reported. The tribological tests are carried out using four ball testers in accordance with ASTM D4172-18 requirements. NiO-NPs are utilised as lubricating additives in poly alpha olefin (PAO4) base oil. NiO-NPs in PAO4 at a concentration of 0.5 wt% improved the coefficient of friction, and positive results are observed.