Nitrate Trihydrate Research Articles

Copper nitrate as a powerful and eco-friendly natural catalyst for mediator-free aerobic oxidation of 2,3-dihydroquinazolinones and 1,4-dihydropyridines under mild conditions

For the first time, copper (II) nitrate trihydrate was used as an efficient, eco-friendly, operational ease, inexpensive, and commercially available catalyst for the biomimetic aerobic oxidation synthesis of quinazolinones and Hantzsch pyridines from their corresponding 2,3-dihydroquinazolinones and 1,4-dihydropyridines, respectively. The products were achieved in satisfactory to excellent yields using acetonitrile as the solvent. These methods are considered to be more eco-friendly, efficient, uncomplicated, and useful compared to existing ones as they align with various principles of green chemistry. Hence, these techniques can be utilized in pharmaceuticals and other delicate synthesis processes.

Thermal performance and flash point analyses of concentrator photovoltaic (CPV) system using multiple types of PCMs and various panel inclination angles under the effect of a constant heat flux

This numerical study conducts a comparative analysis of various phase change materials (PCMs) including Lauric Acid, Paraffin, RT 24, RT 31, RT 35, RT 38, RT 42, RT 47, RT 50, and Lithium Nitrate Trihydrate (LiNO3.3H2O) to assess their suitability for optimizing the thermal management of a solar concentrator photovoltaic (CPV) system. The analysis focuses on the temperature regulation capabilities, melting dynamics of the used PCMs, along the electrical efficiency of the CPV system across a range of inclination angles (0°, 15°, 30°, 45°, 60°, 75°, and 90°) under a constant heat flux of 1000 W/m². The research aims to identify the most effective solutions for enhancing the efficiency and reliability of solar concentrator systems. Key considerations such as PCM’s flash points, liquid fraction and convective behavior are addressed for each PCM type. Numerical results obtained using ANSYS Fluent indicate that Lithium Nitrate Trihydrate (LiNO3.3H2O) outperformed most paraffin-based PCMs, such as RT 24 and RT 35, with around 24 % higher electrical efficiency. Although Lauric Acid was approximately 19.5 % less efficient than Lithium Nitrate Trihydrate, it offered superior long-term thermal stability due to its slower melting rate and phase change temperature of 43–44°C, taking 45.33 % longer to melt compared to Paraffin RT 24. RT 50, with its higher melting temperature of 50°C, provided a balance between melting period and efficiency, making it an ideal PCM for applications requiring both moderate efficiency and sustained thermal regulation.

Indole-3-Carbinol Upconversion with Copper Oxide Nanoparticles Supported Graphitic Carbon Nitride: A Sustainable Approach

Electro-organic chemistry offers a sustainable and efficient approach to organic synthesis by utilizing electrochemical processes. This field has gained significant attention due to its potential for minimizing waste, reducing energy consumption, and enabling selective transformations. Herein, we report the development of a graphitic carbon nitride-coated carbon fiber electrode modified with electropolymerized amino-2-thiazole and electrodeposited Cu2O nanoparticles from copper nitrate trihydrate for the oxidation of Indole-3-carbinol (IC). Scanning electron microscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy studies were carried out to characterize the developed electrode. Cyclic voltammetry, electrochemical impedance spectroscopy, and bulk electrolysis techniques were employed for the electrochemical studies. The enhanced electrochemical activity of the Cu2O-pAT-GCN-TCFP electrode compared to the individual GCN and polymer electrode was studied using electrochemical characterization, which revealed a 3-fold increase in the current response for Cu2O-pAT-GCN-TCFP (0.0011 A) compared to the bare electrode. The reaction was carried out using an aqueous carbonate buffer solution as an electrolyte via bulk electrolysis at a set potential of 0.82 V. The product obtained was isolated by column chromatography to obtain a yield of 74% and characterized by proton nuclear magnetic resonance (1H NMR) spectroscopy. Additionally, the Cu2O-pAT-GCN-TCFP electrode was studied for its stability, reproducibility, and selectivity.

Solvent-Free Synthesis of HKUST-1 with Abundant Defect Sites and Its Catalytic Performance in the Esterification Reaction of Oleic Acid.

HKUST-1 has received increasing attention because of its potential applications in many fields, such as heterogeneous catalysis, sensors, gas storage, and separation. Herein, we report that HKUST-1 can be facilely prepared by heating a ground mixture of copper nitrate trihydrate and 1,3,5-benzenetricarboxylic acid in an autoclave at 80 °C for 10 h. The data from nitrogen sorption show that the obtained material, named HKUST-1-free, possesses a high BET specific surface area of 1671 m2/g and a pore volume of 0.8 cm3/g. The results from acid-base titration indicate that the number of defect sites in HKUST-1-free is more than that in HKUST-1-solvent prepared by the solvothermal method. As a heterogeneous catalyst, HKUST-1-free gave a high yield (91%) of methyl oleate in the esterification reaction of oleic acid with methanol at room temperature compared to HKUST-1-solvent (70%). Additionally, it is proven that HKUST-1-free is a heterogeneous catalyst and can be reused.

Synthesis and Reactions of Pentacycloundecane Derivatives Related to Cookson’s Dione

AbstractIn this study, a pentacyclic keto-olefin was treated with thallium(III) nitrate trihydrate, resulting in the formation of mono ring-expanded product. However, when the corresponding dialkene was treated with thallium(III) nitrate trihydrate, an unexpected ring-closure product was obtained instead of the expected double ring-expanded product. The use of the Tebbe reagent facilitated the olefination of hindered and enolizable cage dione derivatives, converting both keto moieties into methylene groups and forming the desired diolefin. Notably, conventional Wittig reagents proved to be ineffective in the olefination sequence with cage diones.

Green synthesis and characterization of CuO, Fe2O3 and CuO/Fe2O3 compounds investigation

Green chemistry techniques are increasingly being used to produce nanomaterials from easily accessible natural resources. The present study utilized a cost-effective and environmentally sustainable method to separately synthesize copper oxide, iron oxide, and mixed oxide nanoparticles. Copper (II) nitrate trihydrate and iron (III) nitrate nonahydrate were utilized as precursors with the help of fruit peel extracts. The nano-oxides were synthesized from the local fruit peels, specifically orange, cherry, and sidra (Ziziphus jujuba), by a simple procedure that involved heating the peels with distilled water, filtration, adding precursor, and calcination. Experiments were conducted on the resultant powders to evaluate their structural, biological, and physical characteristics. The results of the X-ray diffraction analysis showed that pure crystallite structures of CuO and Fe2O3 were formed, ternary compound CuFeO2 (delafossite), and CuO/Fe2O3 (nanocomposite) were synthesized, and their purity was verified through energy dispersive X-rays (EDX). The findings from scanning electron microscopy (SEM) and particle size analysis (PSA) revealed that the nanoparticles are semi-spherical, with particle sizes ranging from 83.9 to 118.7 nm for CuO, from 95.2 to 119.8 nm for Fe2O3, and from 60.6 to 90.4 nm for mixed oxides extracted from three fruit peels. The conducted experiments on bacterial and fungal resistance revealed that the produced oxides are effective antibacterial and antifungal particles. The synthesized nanoparticles were also analyzed through AFM and Toxicity.

Designing a new bio-active copper(II)-triazole ester type complex based on copper(II)-catalyzed reaction

The reaction of copper(II) nitrate trihydrate with N,Nʹ-cyclohexane-1,2-diylidene-bis(4-chlorobenzoylhydrazide) (LCl) in acetonitrile produced a mononuclear Cu(II) complex [CuII(TECl)2(NO3)2] (TECl: triazole-ester) (1). Triazole-ester is an intermediate compound formed during the oxidation of LCl by copper ion based on Cu(II) catalyzed click reaction. The organic ligand (LCl) and its complex (1) are characterized with different techniques. According to single crystal X-ray crystallography, complex 1 has been verified to possess a distorted square planar geometry and functions as a four-coordinate mononuclear copper(II) complex. Furthermore, the Cu(II) ion coordinates to the 1-N atoms of two monodentate (TECl) molecules, along with the N atoms of two monodentate nitrate ions. The optimization of geometry and other functional analyses was executed using density functional theory (DFT). Additionally, molecular electrostatic potential (MEP) and Hirshfeld surface analyses were conducted to scrutinize the reactive regions within the crystals. Employing molecular modeling software, the most suitable conformational bond between the prepared compounds (LCl and 1) and the urease enzyme is investigated to calculate the structure–activity relationship and binding energies. Moreover, comprehensive studies were performed on in vitro enzyme inhibition, pharmacokinetics, enzyme kinetic mechanism, and antimicrobial activity. These investigations revealed that the synthesized compounds exhibit a pronounced affinity for binding to the urease enzyme. Furthermore, the compounds demonstrate promising inhibitory potential against select bacterial strains and the urease enzyme, as evidenced by their MIC and IC50 values.

Highly Efficient Non-Enzymatic Electrochemical Glucose Biosensor Based on Copper Metal Organic Framework Coated on Graphite Sheet

Detection of glucose is highly informative, creating a constant demand for fabricating high-precision glucose biosensors. Metal–organic frameworks, a family of porous materials renowned for their tunability, can be an excellent choice for developing such sensors. We have developed a highly-sensitive, non-enzymatic sensor for electrochemical detection of glucose fabricated using Copper Metal–Organic Framework (Cu MOF), synthesized by a simple, room-temperature stirring method using Benzene-1,3,5-tricarboxylic acid (BTC) as ligand and Copper nitrate trihydrate as precursor. The synthesized nanostructure was characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray analytical techniques. Powder X-ray diffraction study and thermogravimetric analysis were also done. Further, Brunnauer-Emmett-Teller analysis revealed the porous nature of Cu MOF. The materials exhibited strong electro-catalytic activity for glucose oxidation as revealed from cyclic voltammetry and chronoamperometric studies done under alkaline pH conditions. The Cu MOF deposited on a conducting graphite sheet electrode displayed a significantly low detection limit of 0.019 mM through a broad detection range (1–15 mM) and a strong sensitivity of 229.4 μAmM−1 cm2. Overall, the Cu MOF/GS exhibits exceptional stability, short response time (less than 1 s), and good repeatability and reproducibility, making it a promising future material for non-enzymatic glucose detection.

High Power Density Thermal Energy Storage With Phase Change Material in Enhanced Compact Heat Exchangers

Abstract Performance of a novel ultracompact thermal energy storage (TES) heat exchanger, designed as a microchannel finned-tube exchanger is presented. With water as the heating–cooling fluid in the microchannels, a salt hydrate phase change material (PCM), lithium nitrate trihydrate (LiNO3 · 3H2O), was encased on the fin side. To establish the hypothesis that small-length-scale encasement (<3 mm) of PCM substantially enhances heat transfer to yield very high power-density energy storage, heat exchanger designs with 10 and 24 fins/inch were considered. They were subjected to thermal cycling, or repeated heating (melting) and cooling (freezing), with inlet fluid flow mimicking diurnal variation between 42 °C and 25 °C (representing typical arid-region conditions) over an accelerated time period. By employing salt self-seeding to obviate subcooling during cooling or recrystallization, the TES was found to exhibit stable long-term (100 heating–cooling cycles) operation with very high PCM-side heat transfer coefficients (∼100–500 W/m2 K) and storage power density (∼160–175 kW/m3). In fact, with optimization of heating–cooling fluid flowrate for given charging–discharging time period and exchanger size, power density >300 kW/m3 can be achieved. The results clearly establish that highly compact heat exchangers used as TES units can provide very high-performance alternatives to conventional ones.

Preparation and characterization of ZnO/CuO nanocomposites thin films for highly efficient visible-light photocatalysis of acriflavine dye

Chemical bath deposition (CBD) was used to grow ZnO nanorods on glass substrates. Grown ZnO nanorods are dipped in a copper nitrate trihydrate [Cu(NO3)2.3 H2O] solution at 90 °C for 30 min before being annealed at 400 °C for 1 h to convert Cu2+ ions to CuO nanoparticles, forming a ZnO/CuO thin films nanocomposite. Images obtained from a Field Emission Scanning Electron Microscope (FESEM) indicated that the ZnO structure consisted of nanorods coated in CuO nanoparticles. The optical absorption of both ZnO NRs and ZnO/CuO nanocomposites thin films was strongly edged, with an energy gap of 3.26 and 3.21 eV, respectively. The photodegradation rate of the manufactured ZnO NRs and ZnO/CuO nanocomposites thin films against Acriflavin dye was investigated at room temperature under varying pH conditions and period exposure to visible light. The rate of photodegradation of the dye was increased by increasing the time it was exposed to light and/or the pH of the solution. The photodegradation rates for AFN dye under visible light irradiation ranged from 36% to 100% as the pH value was increased from 4 to 10, and from 78% to 66% at a pH value of 12 and reduced to 78% at a pH value of 12 after 330 min of irradiation. Furthermore, the trapping experiments of reactive species for Acriflavin dye degradation by ZnO/CuO nanocomposites photocatalysts were also carried out

Synthesis and Characterization of Copper-Nickel Based Metal Organic Framework by Co-Precipitation Methode: Properties and Possible Application

CuNi-BTC was synthesized using the co-precipitation method with precursors copper (II) nitrate trihydrate, nickel nitrate trihydrate, benzene-1,3,5-tricarboxylic acid, and the addition of 10 wt% triethanolamine (TEOA) as a modulator. The synthesis was conducted at room temperature and dried at 60°C for 24 hours. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Fourier-Transform Infrared (FTIR), Brunnauer-Emmet-Teller (BET), and electrochemical measurement are techniques employed for the characterization of the material. The diffraction patterns of CuNi-BTC show similar diffraction peaks of the HKUST-1 at 2θ of 6.7°, 9.5°, 11.5°, and 13.4°, respectively. The morphology of CuNi-BTC has an octahedral shape with a pore on its surface. The BET analyses show that the surface area of CuNi-BTC is 534 m2/g with pore and diameter volumes of 0.044 cm3/g and 1.60 nm, respectively. The nitrogen adsorption-desorption isotherm graph shows the type IV characteristic of a mesoporous material. The electrochemical performance of the material was observed by cyclic voltammetry (CV) methods. The CuNi-BTC has current reduction and oxidation values of 4.46 and 3.38 μA, respectively, and has good stability at various scan rates between 10 – 100 mvs-1.

Pengaruh Penambahan Monoetanolamin (MEA) pada Sifat Listrik dari Material Copper Tin Oxide

Semiconductors are materials with interesting electrical properties. Copper tin oxide (CuSnO3) is an oxide semiconductor material with a band gap value of 2.0-2.5 eV. The method used is sol-gel method with the addition of monoethanolamine (MEA). Copper (II) nitrate trihydrate and tin (II) chloride dihydrate as precursors and methanol as solvent. The purpose of this research is to see the effect of MEA addition on the electrical properties of CuSnO3. Characterization results using UV-DRS showed the band gap of CuSnO3 obtained with the addition of 1.5 mL of MEA was 1.71 eV and without the addition of MEA was 2.36 eV. The addition of MEA can reduce the band gap value. Electrical conductivity will be better with the smaller band gap value.

Structural, spectroscopic, theoretical calculation and Hirshfeld surface analyses of 3-D supramolecular dinuclear zinc(II) and copper(II) complexes

Two three-dimensional dinuclear zinc(II) and copper(II) complexes, [Zn2(L2)2(CH3COO)2] (1) and [Cu2(L2)2(NO3)2] (2) (HL2 = 1-(2-{[(E)-2-hydroxy-benzyli-dene]amino}phenyl)ethanone oxime), were synthesized by Zn(II) acetate tetrahydrate or Cu(II) nitrate trihydrate with based ligand HL1 (2-(2-phenoxy)-4-methyl-1,2-quinazoline-N3-oxide, H is the deprotonate hydrogen) originally. HL1 and both complexes were characterized by elemental analyses and spectroscopic methods, as well as were confirmed by single-crystal X-ray crystallography. It was revealed that two complexes had 2:2 ligand-to-metal ratios and 1 was hexa-coordinated whereas 2 was penta-coordinated. In the crystal structures, HL1 showed a chain-like, while complexes showed 2-D network stacking constructions, and both complexes further formed a 3-D supramolecular structure. The frontier molecular orbital energy of all compounds was calculated, and TD-DFT calculations were performed to analyze the electronic transitions of HL1 and both complexes. Additionally, the structural optimization and electronic transitions of the molecules were obtained via DFT calculations, molecular electrostatic potential (ESP), Hirshfeld surface analysis (HSA), and two-dimensional fingerprint (2D-FP), supporting X-ray diffraction results with the existence of the H···H and C/O···H bonds as the main interactions in the crystal lattice. Especially, cyclic voltammetry (CV) and electron paramagnetic resonance (EPR) spectroscopy properties of 2 were further analyzed. In terms of biological applications, all compounds were investigated for antibacterial activity, and the results displayed two complexes had the best antibacterial performance than others.

Energy recovery from the enclosures between the glassing covers in a compact photovoltaic thermal collector

The awareness of bearing the cost due to the release of carbon dioxide in the atmosphere encourages people and governments to reduce their carbon emissions through the optimization of energy production devices. This research was performed for this purpose. Compact (Integrated) solar water heater (CSWH) is the most cost-effective collector due to its simple design. The use of two glass covers along with flat reflectors has increased the efficiency of this collector. In such system, energy recovery from the enclosures between the glassing covers was not reported. In this paper, the simulation for an enhanced compact photovoltaic thermal (PVT) system in EES software is conducted. The collector is a triple production in the form of hot water (stored in water storage tank), hot air (stored in multistage phase change materials (PCMs) due to energy released from the collector two air enclosures), and electricity (generated by a-Si semi-transparent module as an absorber plate). Simulation results show a 3.4% increase in the thermal efficiency of the proposed system compared to the previous passive systems. The minimum required masses for PCMs inside two cascade tanks were obtained 8.6 (kg) of BioPCMQ23 type, and 18.7 (kg) of Lithium Nitrate Trihydrate type.

Electrodeposition of nanostructured copper oxide (CuO) coatings as spectrally solar selective absorber: Structural, optical and electrical properties

Herein, a nanostructured CuO coatings as selective solar absorber (SSA) was fabricated through electrochemical deposition and thermal oxidation techniques. Initially, the copper (Cu) thin films were electrodeposited from copper nitrate trihydrate (Cu(NO3)2·3H2O) electrolyte at 15, 20, and 25 min on the electrode or stainless steel (SS) substrate at room temperature and then annealed in a furnace in the presence of oxygen (O2). The surface morphology, structural, and compositional analysis of the coatings were characterized using scanning electron microscopy (SEM), Atomic force microscopic (AFM), X-Ray Diffraction (XRD), and Energy-dispersive X-Ray Spectroscopy (EDX). The surface morphology confirms the presence of nanowall-like structures and exhibits grain growth as well as an increment in surface roughness with deposition time. The XRD patterns reveal well-crystalline monoclinic nature of CuO, and EDX spectra confirm high-purity phase composition of CuO coatings. Raman spectra show peaks at 305, 344, and 642 cm−1 attributed to Raman active (Ag + 2Bg) modes for characteristics of CuO lattice vibrations. A nanoprofilometer was used to measure the thickness of the coatings and found to be 42, 60, and 74 nm at 15, 20, and 25 min deposition time, respectively. The electrical properties of the prepared films were examined using Keithley 617 programmable electrometer at room temperature which showed the lowest resistivity (ρ) of 1.19x102 Ωcm at 25 min deposition time. The optical properties of the obtained CuO coatings were characterized using UV–Vis-NIR and IR spectrophotometers in the wavelength range of 0.3–2.5 μm and 2.5–20 μm, respectively. The CuO exhibits a higher solar absorptance (α) value of 0.92 and infrared emissivity (ε) of 0.28 at the deposition of 25 min. The optical band gap energy (Eg) of the obtained CuO coatings was estimated using Kubelka-Munk (K-M) model from the diffuse reflectance spectra and found in the range of 1.45–1.50 eV; the lower band gap values are attributed to higher solar absorption. Several parameters, such as crystallinity, grain growth, and stress of the coatings, may influence the optical band-gap energy (Eg).

A mononuclear N,N,N,O donor schiff base Cu(II) complex inhibits bacterial biofilm formation and promotes apoptosis and cell cycle arrest in prostate cancer cells

In this work, we report a distorted square pyramidal mononuclear copper(II) complex [Cu(L)(NCS)] (1) which was obtained by the reaction of the aqueous solution of ammonium thiocyanate to a methanolic solution of copper nitrate trihydrate and corresponding Schiff-base ligands. Schiff bases, HL (C12H19N3O) act as a tetradentate Schiff base, derived from 1:1 condensation of o-hydroxyacetophenone and diethylenetriamine. The synthesized complex has been successfully characterized based on elemental analysis and Infrared (IR) spectroscopy. The structure of complex 1 was confirmed by single-crystal X-ray diffraction study. In our study, we investigated synthesis, structural characterization, antimicrobial, anti-biofilm, and anti-cancer activity, and plausible mechanism of action of a novel mononuclear copper(II) schiff base complex. Increasing microbial resistance to several commercially available or traditional antimicrobial compounds has become a major global health concern at present time. The mononuclear copper(II) complex exhibited potential antibacterial activity against two strains of the gram-negative pathogen Pseudomonas aeruginosa. The copper compound dependent damage of bacterial cell membrane and inhibition of bacterial biofilm formation were also identified. Moreover, complex 1 inhibited prostate cancer cell growth, and migration by inducing apoptosis and arresting the cell cycle at the G2/M phase. Based on the results, we are suggesting our novel mononuclear copper(II) compound as a potential candidate for the development of new antibacterial and anti-cancer drugs.

Crystal Nanoarchitectonics and Characterization of the Octahedral Iron(III)–Nitrate Complexes with Isomer Dimethylurea Ligands

Three octahedral iron(III) nitrate complexes with dimethylated urea ligand isomers, [hexakis(N,N’-dimethylurea-O)iron(III)] nitrate (compound 1), trans-[diaquatetrakis(N,N-dimethylurea-O)iron(III)] nitrate (compound 2), and [hexakis(N,N-dimethylurea-O)iron(III)] nitrate trihydrate (compound 3) were prepared and characterized with single crystal X-ray diffraction, IR, Raman and UV–Vis methods. In compounds 1 and 3, six dimethylurea ligands coordinate to the central FeIII ion via the oxygen in octahedral geometry and the ligands are arranged in a propeller-like manner, dividing the complex cations into two sides. In compound 1, the dimethylurea propellers screw in the opposite direction on the two sides of the complex and in compound 3, they are arranged with the same handedness on the two sides. The complexes have helical chirality. The two sides of the complex cations differ not only in the rotation direction of the ligands but also in the hydrogen bond formation. On one side of the complex cation, the ligands form intermolecular hydrogen bonds only with the crystal waters, meanwhile on the other side of the complex, the ligands form hydrogen bonds only with the nitrate ions. In compound 2, [Fe(N,N-dimethylurea)4(H2O)2]3+ cations form layers that are separated by interconnected NO3− ions forming a hydrogen bonding system and connecting the complex cations A-s and B-s. The three crystallographically different nitrate ions each form four hydrogen bonds in a way that they have one bidentate O atom and two monodentate O atoms; however, the anions differ in their hydrogen bonding. The spectroscopic characteristics of compound 2 were determined by IR measurements on the deuterated compound 2 as well.

Synergistic antibacterial study of nano-Cu2O/CuO@Ag-tetracycline composites

The rapid increase in drug resistance has not reduced the antibacterial activity of most antibacterial drugs but also brought great challenges to society. Therefore, there is an urgent need to develop new antibacterial agents. In this study, copper nitrate trihydrate [Cu(NO3)2·3H2O] was used as a raw material and hydrazine hydrate as a reducing agent to prepare cuprous oxide (Cu2O/CuO). Next, silver nitrate (AgNO3) was added and monomeric silver was loaded on the surface of Cu2O by in situ reduction to obtain Cu2O/CuO@Ag composites. Lastly, nano-Cu2O/CuO@Ag-tetracycline composites were obtained by combining them with tetracycline. Systematic characterization of inhibitors was conducted using transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FT-IR), and ultraviolet–visible spectroscopy (UV–vis). The inhibitory properties and mechanism of Cu2O/CuO@Ag-tetracycline on the Gram-positive bacterium Staphylococcus aureus (S. aureus), Gram-negative bacterium Escherichia coli (E. coli), and drug-resistant bacterium Salmonella (T-Salmonella) were studied. The inhibition performance study showed that the inhibition rate of Cu2O@CuO@Ag-tetracycline was almost 99.99% against the three tested bacteria at 40 min when used at a concentration of 150 μg/mL. Compared with tetracycline and Cu2O/CuO alone, Cu2O/CuO-tetracycline composites have several times higher antibacterial efficiency against E. coli, S. aureus and T-Salmonella. Moreover, the nano-Cu2O/CuO@Ag-tetracycline composites were most sensitive to E. coli. The inhibition mechanism revealed that the nanocomposites could effectively destroy the cell wall of Gram-negative bacteria, enter the cell interior, inhibit cell respiration, and eventually lead to bacterial rupture and death. The nano-Cu2O/CuO@Ag-tetracycline composites exhibited excellent antibacterial properties, indicating their wide application prospects in the fields of medical devices and medical materials.

Using Nigella Sativa Seeds Extract for the Biosynthesis, Characterization and Antimicrobial Activity of CuO Nps

Researchers are interested in green technology because it is a low-risk, eco-friendly and affordable way to biosynthesize nanoparticles (NPs). Copper nitrate trihydrate and Nigella sativa extract were used as a reducing and capping agent during the manufacture of copper oxide (CuO) NPs in this investigation. The biosynthesized CuO NPs were characterized using X-ray diffractometer, transmission electron microscopy, UV–Vis spectroscopy, scanning electron microscopy and Fourier transform infrared (FTIR) spectroscopy. The good crystalline nature perfectly matches the monoclinic structure of bulk CuO. The results obtained from TEM also showed that CuO NPs were semi-spherical in shape, while the zeta potential characterization indicated that the prepared particles have low stability. Moreover, CuO NPs showed good antimicrobial activity.

Wet chemical synthesis and characterization of CuO nanoparticles and their application in pool boiling heat transfer

There are several ways to synthesis nanoparticles, including chemical, physical, and biological processes. In general, chemical approaches are thought to be the most effective for producing uniformly sized and stable nanoparticles. This study deals with the synthesis and characterization of copper oxide nanoparticles (CuO-NPs) that could be used in pool boiling heat transfer in the form of nanofluid. The wet chemical synthesis method was used in order to prepare copper oxide nanoparticles (CuO-NPs) using precursor copper nitrate trihydrate (Cu(NO3)2⋅3H2O) and citric acid in a molar ratio of 5:1 in ethylene glycol (C2H6O2) solvent. The nanoparticles were identified using their stability, crystal size, and particle size. FTIR, XRD, and UV–Visible Spectroscopy all provide evidence that CuO-NPs exist. The typical nanoparticle size, as determined by Zetasizer, was 72.87 nm. The Scherrer formula was used to ascertain the average crystallite size of nanoparticles, which was determined to be approximately 19.82 nm. Positive findings from the stability test on nanoparticles were obtained, and their zeta potential was about –32.51 mV. According to morphological analyses by SEM, the synthesized CuO-NPs were made up of evenly dispersed spheroid-shaped particles that were agglomerated. The amount of reducing agent and calcination temperatures has a significant impact on the nanoparticle's size. The results of the experiment show that the addition of nanoparticles has a significant impact on the value of critical heat flux (CHF).