Synthesis Of Copper Nanoparticles Research Articles

Oxidation of Copper Nanoparticles Protected with Different Coatings and Stored under Ambient Conditions

The synthesis of copper nanoparticles (Cu NPs) stable to chemical oxidation has attracted much attention due to their novel application possibilities. The physicochemical properties of Cu NPs define their utilization in diverse fields, including biological applications, solar cells, high conductivity inks for printed electronics, and other specific applications. In this study we present the synthesis of oxide-free Cu NPs by wet chemistry routes and their chemical oxidation during the storage exposed to ambient conditions. The Cu NPs synthesized in PAAm and AAm/glycerol presence exhibit no oxidation during synthesis and atmospheric conditions storage for 60 and 37 months, respectively. The obtained results compared with those coming from oxidation of partially passivated commercial Cu NPs at 99.8% purity, are presented. The role of the Cu NPs coating is critical to avoid oxidation, and it can be an important feature to achieve good dispersion in different polymers. The Cu NPs oxidation was studied by XRD, TGA, TEM, FTIR, and HR-TEM.

Bioremediation and extracellular synthesis of copper nanoparticles from wastewater using Yarrowia lipolytica AUMC 9256

THIS THE FIRST study describing the rapid extracellular synthesis of copper nanoparticles during the bioremediation of copper by living, autoclaved and dried biomass of Yarrowia lipolytica AUMC 9256. The time course growth in the presence of different concentrations of Cu(II) was studied. The minimum inhibitory concentration value of Y. lipolytica AUMC 9256 for Cu(II) was 1900mg/L. The cellular localization of bioaccumulated copper ions was assessed. Maximum uptake capacities were accomplished at pH 6.0, initial metal ion concentration 450mg/L, biomass dosage 1g/L and contact time 180min for live cells, 90min for autoclaved and 30min for dried biomass. Copper nanoparticles were characterized by UV-Visible spectrophotometer and transmission electron microscopy. They were all spherical in shape with an average size of 32.85nm (live), 22.34nm (autoclaved) and 15.62nm (dried). The occurrence of extracellular complexation, precipitation, adsorption onto cell wall and sequestration of needle-, rod-shaped precipitates within central large vacuole during Cu(II) uptake by live biomass were found out by transmission electron microscopy. Fourier Transform Infrared spectroscopy confirmed that mannans, phosphorus, P=S stretching, C-S stretching, M-O and ring deformation were more included in Cu(II) uptake by dried biomass. Energy dispersive X-ray microanalysis confirmed the presence of high-intensity characteristic peaks of Cu(II) and a sharp reduction of atomic % of phosphorus and potassium on the cell wall. X-ray powder diffraction patterns of Cu(II)-loaded biomass confirmed their crystalline nature. The removal of copper from ceramic industry wastewater was carried out by dried biomass effectively.

Synthesis of copper nanoparticles supported on MoO3 using Sun spurge leaf extract and their catalytic activity

Copper nanoparticles supported on MoO3 (Cu NPs/MoO3) were prepared by a green method using Sun spurge leaf extract. Cu NPs/MoO3 nanoparticles were characterized by X‐ray diffraction analysis, energy dispersive X‐ray analysis, scanning electron microscope and transmission electron microscope. The catalytic activity of this well‐defined material in three‐component CuAAC reactions was tested to produce 1,4‐disubstituted‐1,2,3‐triazoles in good to excellent yields in water as a green solvent. More importantly, the catalyst can be recovered and reused efficiently up to five consecutive cycles with no significant loss of catalytic activity.

Effect of Electrolyte Concentration during Solution Plasma on Copper Nanoparticle Size

This research was conducted to investigate the effect of electrolyte concentration of solution plasma on copper nanoparticles size. Copper nanoparticles with the size between 1-100 nm have received a huge interest because of their optical, catalytic and electrical conducting properties. Electrolysis via solution plasma method has many advantages such as its cost effectiveness, simplicity, eco-friendliness, and less energy requirements compared to other methods. To synthesize copper nanoparticles via solution plasma, two wires of copper and platinum as cathode and anode respectively were immersed in a glass beaker of 300 ml of two electrolyte solution (K2CO3 and NaOH) with three different concentrations (0.1 M, 0.5M and 1M), and electrical current was applied similar to an electrolysis process. The images of the nanoparticles were obtained using scanning electron microscopy and their sizes were analyzed using ImageJ software. It was found that when the concentration of K2CO3 increased, the size of copper nanoparticle also increased. However, the size of copper nanoparticles decreased when the concentration of NaOH was increased. This research shows the potential of easily controlling size of copper nanoparticles by changing the electrolyte concentration used during solution plasma process.

Rapid detection of methyltransferases utilizing dumbbell DNA-templated copper nanoparticles

DNA methylation, as an epigenetic event of DNA modification, plays important roles in genetic disorders and diseases, such as cancer, and increasing evidence has shown that DNA methyltransferase (MTase) can be utilized as a biomarker for genetic diseases. In the present study, a smart detection system for DNA methyltransferase was established based on a target-protection principle. In the presence of MTase, as the sensor, dumbbell template DNA (DT DNA) was methylated and resisted endonuclease and exonuclease digestion. Thus, fluorescence was able to be rapidly detected after restoring Cu2+ in the detection system above. However, if the template DNA was digested into nucleotides without the protection of MTase, the following step of fluorescence copper nanoparticle (CuNP) synthesis would fail because it is template dependent. Therefore, under optimal conditions, a detection limit of approximately 1.6968 × 10−4 U/μL MTase activity was achieved. In addition, this real sample assay shows promise for potential application in complex environments. Furthermore, the proposed MTase-detection system can be utilized to screen inhibitors or drugs for MTase.

In situ incorporation and loading of copper nanoparticles into a palmitic–lauric phase‐change material on polyester fibers

ABSTRACTThis article introduces a facile approach for applying a eutectic mixture of fatty acid phase‐change materials (PCMs) on polyester fibers for thermal conductivity improvement via the in situ incorporation of copper nanoparticles. For this purpose, a eutectic mixture of palmitic acid and lauric acid was applied as PCMs and ascorbic acid was applied for the synthesis of copper nanoparticles. The thermal properties and stability of the treated samples were also determined by differential scanning calorimetry and thermogravimetry analysis. The treated samples indicated appropriate phase‐transition temperatures between 29.1 and 36.8 °C, with relevant latent heats of 49.4 and 49.9 J/g, respectively. The in situ formation of copper nanoparticles into eutectic fatty acid applied on the polyester fibers resulted in the promotion of the thermal conductivity of the composite by about 100.1% with the maximum amount of nanoparticles. In addition, the treated samples maintained good thermal durability and stability after 100 melting and freezing cycles. In addition, the tensile strength of the treated samples was improved. Overall, this treatment could be used to produce promising form‐stabilized composite PCMs and thermoregulated polymers and textiles with appropriate phase‐transition ranges and thermal conductivity. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 46951.

Green Synthesis of Copper Nanoparticles using Mitragyna parvifolia Plant Bark Extract and Its Antimicrobial Study

In this study, Mitragyna parvifolia plant bark used to prepare aqueous extract which provides cost-effective, eco-friendly process, less time consuming, an environmentally benign, easy and proficient way for the synthesis of copper nanoparticles. Mitragyna parvifolia plant bark was collected from Virpur hills forest area. The Mitragyna parvifolia plant bark extract was prepared with deionised water and used for the green synthesis of copper nanoparticles. The colour change of the solution dark brown from pale yellow colour confirms the formation of copper nanoparticles. The green synthesised copper nanoparticles were characterised by UV-visible spectroscopy, FT-IR, XRD, SEM, TEM and their antimicrobial activity was also investigated. UV-visible spectral result confirmed the reduction of copper sulphate to copper nanoparticles. FTIR analysis also supported for the formation of copper nanoparticles. Crystallinity of Cu NPs was find out by XRD study and the morphology of the particles was analysed with the help of scanning electron microscopy and found spherical in nature. The antibacterial activity experiment done against Escherichia coli, gram-negative and Bacillus subtilis, gram-positive bacteria by agar well method and the maximum zone of inhibition was higher in gram-positive bacteria compared to gram-negative bacteria. The green synthesised copper nanoparticles proved to be potential candidates for medical application where the antimicrobial activity is highly essential.

Synthesis and Characterization of Water Soluble Fluorescent Copper Nanoparticles

Synthesis and Characterization of Water Soluble Fluorescent Copper Nanoparticles

Effective control of particle size, surface plasmon resonance and stoichiometry of Cu@CuxO nanoparticles synthesized by laser ablation of Cu in distilled water

Pulsed laser ablation of copper in distilled water is used to synthesize copper nanoparticles as a function of duration of laser ablation and incident laser energy. Increase in the ablation time from 15 to 60 min at fixed incident laser energy of 30 mJ resulted in blue shift of the surface plasmon resonance peak from 641 to 626 nm along with a broadening of the plasmon bandwidth from 127 to 165 nm, respectively. The increase in incident laser energy from 30 to 70 mJ at fixed duration of 60 min ablation induced a similar blue shift in the plasmon peak from 626 to 617 nm and a corresponding increase in the bandwidth from 165 to 209 nm, respectively. These observations are due to reduction in the size of the nanoparticles as also confirmed by the transmission electron microscopic images. Nearly uniform particle size distribution is observed for an ablation time of 60 min. An increase in laser energy from 30 to 70 mJ keeping the ablation time fixed for 60 min resulted in decrease in the average size of the nanoparticles from 20 to 7 nm, respectively. The structural studies via selected area electron diffraction and Raman analysis revealed that the extent of oxidation taking place in the synthesized nanoparticles of Cu@CuxO also varies with the laser ablation duration and incident laser energy. For the samples prepared with 30 mJ of incident laser energy and laser ablation duration upto 30 min, Cu2O phase of the nanoparticles is dominant whereas for an increased duration of 60 min at the same laser energy, there is an appearance of CuO phase. The increase in laser energy upto 70 mJ for 60 min of ablation duration resulted in CuO as the dominating phase. It has been established that by merely varying the laser ablation duration and the incident energy, particle size, plasmonic response and structural properties of the synthesized nanoparticles can be effectively tuned.

Green Synthesis of Colloidal Copper Nanoparticles Capped with Tinospora cordifolia and Its Application in Catalytic Degradation in Textile Dye: An Ecologically Sound Approach

Green synthesis has been considered as an ideal approach owing to its simplicity, cost effectiveness and minimal toxicity. Aim of the present study was to synthesize and characterize copper nanoparticle capped Tinospora cordifolia using green synthesis and further to evaluate its catalytic degradation property on different dyes. Various characterization parameters were performed such as particle size, PDI, zeta potential, microscopic study (SEM, TEM), interaction study through ATR-FTIR and DSC. Surface area of the sample was analyzed through the surface area analyzer. Catalytic degradation ability of synthesized nanoparticle was studied using various dyes such as reactive dye, direct dye, eosin yellowish and safranin.

SYNTHESIS OF COPPER NANOPARTICLES USING ASCORBIC ACID AND CETYL TRIMETHYL AMMONIUM BROMIDE

Objective: The present study highlights the development of a method to synthesize copper nanoparticles (CuNPs).Methods: CuNPs were developed using 0.01 M copper penta sulfate and 0.11 M of ascorbic acid (AA) and 0.03 M of cetyl trimethyl ammonium bromide solution. The synthesized CuNPs were differentiated through filtration and washed by water (deionized). CuNPs were kept in dialysis bag 70 KD in a 250 mL glass beaker along with distilled water. The assembly was kept on a magnetic stirrer for 24 h at 500 rpm. Then, the dialysis bag containing CuNPs solution was filtered by a filter assembly with 0.2 μm nylon filter. The filtered CuNPs were spray dried with the help of spray drier.Results: The prepared CuNPs were found to be 440 nm with zeta potential of −10 mV and polydispersity index 0.314.Conclusion: The investigation deciphers the promising and material technique to synthesis of CuNPs by methods for synthetic reduction utilizing strategy using AA (0.2 M) and sodium hydroxide (1 M), and Syloid 244FP.

Synthesis and characterization of isotopically-labeled silver, copper and zinc oxide nanoparticles for tracing studies in plants

In parallel to technological advances and ever-increasing use of nanoparticles in industry, agriculture and consumer products, the potential ecotoxicity of nanoparticles and their potential accumulation in ecosystems is of increasing concern. Because scientific reports raise a concern regarding nanoparticle toxicity to plants, understanding of their bioaccumulation has become critical and demands more research. Here, the synthesis of isotopically-labeled nanoparticles of silver, copper and zinc oxide is reported; it is demonstrated that while maintaining the basic properties of the same unlabeled (“regular”) nanoparticles, labeled nanoparticles enable more sensitive tracing of nanoparticles within plants that have background elemental levels. This technique is particularly useful for working with elements that are present in high abundance in natural environments. As a benchmark, labeled and unlabeled metal nanoparticles (Ag-NP, Cu-NP, ZnO-NP) were synthesized and compared, and then exposed in a series of growth experiments to Arabidopsis thaliana; the NPs were traced in different parts of the plant. All of the synthesized nanoparticles were characterized by TEM, EDS, DLS, ζ-potential and single particle ICP-MS, which provided essential information regarding size, composition, morphology and surface charge of nanoparticles, as well as their stability in suspensions. Tracing studies with A. thaliana showed uptake/retention of nanoparticles that is more significant in roots than in shoots. Single particle ICP-MS, and scanning electron micrographs and EDS of plant roots showed presence of Ag-NPs in particular, localized areas, whereas copper and zinc were found to be distributed over the root tissues, but not as nanoparticles. Thus, nanoparticles in any natural matrix can be replaced easily by their labeled counterparts to trace the accumulation or retention of NPs. Isotopically-labeled nanoparticles enable acquisition of specific results, even if there are some concentrations of the same elements that originate from other (natural or anthropogenic) sources.

The Influence of Ar on the Synthesis of Carbon-coated Copper Nanoparticles in Gaseous Detonation

Background: Carbon-coated metal nanoparticle is a kind of unique nuclear-shell material that is the carbon shell filled with metal particles. It has a great promising future in the application as excellent solid lubricants additives, conducting resin, antiradiation material and so on. As a mature technology, the gas detonation method has been widely used to synthesize various nanomaterials. Method: Using copper acetylacetonate as a precursor to provide carbon and different concentrations of argon as a protective medium for the first time, high quality carbon-coated copper nanoparticles (Cu@C) were synthesized in hydrogen and oxygen. X-ray Diffraction (XRD), Raman spectroscopy and transmission electron microscopy (TEM) were employed to characterize the structure, phase and constituent of the Cu@C nanoparticles to investigate the influence of argon concentration on the synthesis. Results: The XRD pattern, Raman spectroscopy and TEM images confirm the effect of Ar on synthesizing Cu@C, especially on particle size. The minimum average size is around 13 nm, and most of the particle size distribution is in 5-10 nm range. When the argon concentration is high, the detonation process of H2 and O2 will be suppressed, which is not conducive to the graphitization. Conclusion: Argon gas has a catalytic effect on the synthesis of high-quality Cu@C, which could significantly reduce the particle size of detonation products; the grain size appears an obvious downtrend with the concentration of argon increasing, but the high concentration of Ar is disadvantageous for the graphitization of carbon shells.

One-step fabrication of fatty acids/nano copper/polyester shape-stable composite phase change material for thermal energy management and storage

In this contribution, for the first time, fatty acids/nano copper/polyester composites were prepared by a facile and one-step route through simultaneous in situ formation of copper nanoparticles and direct absorption of fatty acids to polyester fibers for thermal energy management and thermal conductivity improvement. This eliminates synthesis of copper particles in the separate processing and also other processing such as electrospinning of fibers with using solvents and micro and nano encapsulation as well as shortening the time and processing steps. Two eutectics of fatty acids including myristic/lauric acid and myristic/stearic acid were used as phase change materials, ascorbic acid as a clean reducing agent for in situ synthesis of copper nanoparticles and polyester fibers as supporting material. The thermal behavior of the samples was investigated by using differential scanning calorimetry and thermogravimetric analysis. Based on experimental results, the prepared composites provided a proper and wide temperature range of phase transitions from 29.4–34.2 to 35.7–52.7 °C with corresponding enthalpies of 40.3–53.9 and 41.9–55.0 J/g, respectively, that is appropriate for using in diverse applications. The incorporation of copper nanoparticles into eutectic of phase change materials leads to a 77.5% increase in thermal conductivity for the sample treated with lowest copper content. In addition, the treated samples indicated good thermal stability and reliability even after 100 melting and solidifying cycles. Finally, the mentioned method can be utilized for producing shape-stable composite phase change material with appropriate phase transition ranges for low temperature energy storage/retrieval systems.

SYNTHESIS OF BIOLOGICALLY ACTIVE COPPER SOLS IN PRESENCE OF NITRILOTRI(METHYLENE)PHOSPHONIC ACID

In this work the conditions for synthesis of copper nanoparticles by sodium tetrahydroborate in the presence of NTF are optimized. It is proved that the most favorable conditions for the reduction of copper in the solutions with its concentration of 2.0∙10-2 mol/l, are created when the concentration of tetrahydroborate sodium is three to four- fold exceeded, the titratable alkalinity is 5.3∙10-2-10.3∙10-2 mol/l, the temperature is 60 °C and the ratio of cation and chelate is equimolar. The method of photon correlation spectroscopy has confirmed the obtaining of copper nanoparticles with hydrodynamic radius of 25 nm, including shell stabilizers. The immutability of the size of bass for at least 72 h has been revealed.

Ascorbic acid assisted synthesis, characterization and catalytic application of copper nanoparticles

Herein we report the synthesis of copper nanoparticles by simple cost ndash effective eco ndash friendly wet chemical reduction method using L ndash ascorbic acid as reducing agent The synthesized nanoparticles were characterized by X ndash ray diffraction electron microscopy SEM and TEM and BET surface area analyzer The surface area of Cu nanoparticles was found to be times higher than the previous reports The as ndash synthesized Cu nanoparticles were used as catalyst for the degradation of Rhodamine B RhB under both dark and light conditions The Cu nanoparticles showed noteworthy enhancement in the degradation of RhB organic dye

One-Pot Ultrafast Microwave-Assisted Synthesis of Copper and Copper Oxide Nanoparticles

A method of synthesis is presented for the rapid preparation of copper, copper oxide and mixed copper oxide-copper nanoparticles employing a conventional home microwave oven. The nanoparticles were characterized by SEM, XRD and UV-visible spectroscopy. The size and the composition of the nanoparticles were controlled by the heating time. Cuprous oxide nanoparticles were obtained at short heating times and copper nanoparticles at longer times, while mixed cuprous oxide-copper nanoparticles where obtained in an in between window of time.

A Study of Preparation and Characterization of Poly(vinyl alcohol) Coated Copper Nanoparticles in Aqueous Solution

We have developed a new solution-phase chemical reduction method for the synthesis of poly(vinyl alcohol) coated copper nanoparticles in aqueous solution. Copper nitrate is used as the precursor, sodium hypophosphite as the reducing agent, and poly(vinyl alcohol) as the coating agent. The synthesis of copper nanoparticles could be completed within several hours and the copper nanoparticles in powder form could be stored within one week in ambient condition. In Ar atmosphere, the complete thermal decomposition temperature of coated layer was lower than 450 °C. The antioxidative properties of poly(vinyl alcohol) coated copper nanoparticles were evaluated compared to that of polyvinylpyrrolidone coated copper nanoparticles.

Antimicrobial copper nanoparticles synthesized from waste printed circuit boards using advanced chemical technology

Waste Printed Circuit Boards (WPCBs) were classified as one of the most important resources for urban mining containing high purity Copper (Cu) and other valuable materials. Recently, a dissolution recycling approach enhanced by ultrasonic treatment succeeded in the liberation of Cu foils from WPCBs as received. This research aims to synthesize Copper Nanoparticles (Cu-NPs) from the recovered Cu by using an advanced chemistry approach to obtain nano-product with high added value taking into consideration environmental risks. The experiments were carried out on the Cu foils recovered from the three types of WPCBs with different purity of Cu (Motherboard, Video Card, and Random Access Memory (RAM)). The synthesis process was performed in two stages: (a) preparation of Copper (II) Sulfate aqueous solutions from the recovered Cu and (b) chemical reduction of solutions for synthesis of Cu-NPs by using Native Cyclodextrins (NCDs), particularly ß-NCD as stabilizers. The efficiency of the developed approach for raw material of different purity was assessed and the final yield and the estimated recovery cost of synthesized Cu-NPs were calculated with high accuracy as well as the properties of the synthesized Cu-NPs. The obtained Cu-NPs were examined using SEM-EDS, TEM, XRD, Raman Spectroscopy, and TGA. To maximize the potential biomedical application benefits, the antibacterial activity of Cu-NPs was investigated by the standard microdilution method for E. coli, P. aeruginosa, and S. aureus bacterial cultures. The results showed that the produced Cu-NPs had an average size of 7 nm and yield 90%, while the preparation costs were 6 times lower in comparison to the commercial counterparts. In addition, the results indicated that the synthesized Cu-NPs from RAM sample had a good antimicrobial action.

CuNPs decorated molecular imprinted polymer on MWCNT for the electrochemical detection of l-DOPA

A novel synthesis of copper nanoparticle (CuNPs) is carried out by the reduction of ethylene diamine Cu complexes using sodiumborohydride as reducing agent. The synthesized copper nanoparticle is grafted with molecular imprinted polymer on MWCNT (CuNPs/MWCNT-MIPs). Fabricated sorbent is used for the molecular recognition and sensing of levodopa (l-DOPA) in human urine and pharmaceutical samples. The non covalent interaction between l-DOPA and the functional groups present in the selective binding sites of the polymer composite sorbent is mainly responsible for the recognition property. The synthesis of CuNPs decorated MWCNT-MIPs and its extents are characterized by employing UV–Vis spectroscopy, Fourier-transform infrared spectroscopy, powder X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy techniques. The electrochemical investigation shows that the imprinted (CuNPs/MWCNT-MIP) material has good recognition capacity towards l-DOPA. The sensitivity is found to be directly proportional to the concentration of template with a detection limit of 7.23 × 10−9M (S/N = 3). The specificity and selectivity of the fabricated sensor give a fine discrimination between l-DOPA and structurally related compounds such as dopamine, uric acid, 3,4-Dihydroxyphenylacetic acid and homovanillic acid.