Deposition Of Copper Nanoparticles Research Articles

Impact of nano-Y2O3 on the physical, microstructure, and mechanical characteristics of Cu composite fabricated via powder metallurgy

This investigation focused on optimizing the adhesion of Y2O3 nanoparticles for uniform distribution within a copper matrix. Five samples were prepared with varying Y2O3 content (0%, 2.5%, 5%, 7.5%, and 10% by weight). To enhance bonding, a 5% nano silver coating was applied to the Y2O3 particles. The electroless deposition of copper nanoparticles onto the Y2O3 surface ensured even distribution within the matrix. The composite powders were then compressed at 700MPa and sintered at 950 °C for 140minutes. Density verification and microstructural analysis using scanning electron microscopy revealed a uniform distribution. Increasing the Y2O3 content gradually improved hardness, while wear rate measurements using a pin-on-disc method indicated a decrease with higher Y2O3 ratios. Additionally, electrical and thermal conductivity, along with the coefficient of thermal expansion, showed reductions with increasing Y2O3 content. This comprehensive approach provided valuable insights into the structural, mechanical, and conductive properties of the synthesized materials.

An Electrochemical Sensor Based on Cu-MOF-199@MWCNTs Laden with CuNPs for the Sensitive Detection of Creatinine.

In this study, the synthesis of Cu-MOF-199@multiwalled carbon nanotubes (Cu-MOF-199@MWCNTs) composites was achieved and utilized to create an advanced electrochemical sensor for creatinine (Cre) detection. The composites were modified on a glassy carbon electrode surface through direct drip coating, followed by the deposition of copper nanoparticles (CuNPs) via constant potential deposition. Characterized by various techniques and electrochemical analyses, the Cu-MOF-199@MWCNTs composite increased the CuNPs load, improving the detection sensitivity for Cre. Under optimal conditions, the modified electrode exhibited good linearity across a broad range of Cre concentrations (0.05-40.0 μM) with a low detection limit of 11.3 nM. The developed sensor demonstrated remarkable stability, reproducibility, and selectivity, showing promise in sensitive and accurate Cre detection in serum samples.

Development and characterization of conductive textile (polyester fabric) for wearable electronics by using electroless metallization

This paper investigated the development and characterization of conductive textured and non-textured polyester fabrics with various cross-sections. To impart conductivity on fabric structures, the electroless copper plating method was chosen. Electrical conductivity, thickness, electron scanning microscopy (SEM), microscopic morphology, and energy dispersive X-ray spectroscopy were used to characterize the deposition of copper nanoparticles on textured and non-textured polyester fabrics (EDX). SEM images revealed a thin film of uniform copper nanoparticle coating on textured and non-textured polyester fabrics. Electrical conductivity, wear resistance, thickness, and durability of conductive textured polyester fabrics were compared to non-textured conductive polyester fabrics. Electrical conductivity measurements show that both textured and non-textured polyester fabrics have good electrical conductivity values of 27Ω/cm, 85Ω/cm, 52Ω/cm, 9Ω/cm, 98Ω/cm, 133Ω/cm. When conductive polyester fabrics were tested for durability against washing and rubbing fastness, the textured polyester fabrics retained copper nanoparticles well by maintaining their electrical conductivity level after 250 abrasion and washing cycles, with best electrical conductivity values of 177Ω/cm and 29Ω/cm, respectively.

Solar light-driven selective photoelectrochemical CO2 reduction to CO in aqueous media using Si nanowire arrays decorated with Au and Au-based metal nanoparticles

To address recent energy and environmental issues, such as global warming and resource depletion, significant interest has been shown in carbon dioxide (CO2) fixation based on photoelectrochemical processes under solar light irradiation. The present paper describes the applicability of gold nanoparticles-decorated silicon nanowire arrays (Au/SiNW) as photoelectrodes to promote CO2 reduction. The decoration with Au nanoparticles of SiNW was performed by an electroless plating utilizing surface hydrogen-terminated silicon groups, generated during the nanowire formation process. Au/SiNW exhibits efficient photoelectrochemical performance for CO2 reduction to produce CO selectively in an aqueous medium under simulated solar light irradiation owing to its vertically aligned nanowire structure and Au nanoparticles as cocatalysts. The former provides high specific surface area and light trapping effect, and the latter induces selective interaction with CO2. Moreover, a unique two-steps method for Au decoration that consists of photo-assisted deposition of copper nanoparticles and the following electroless plating to replace Cu atoms to Au ones achieves more uniform decoration of SiNW with highly dispersed core–shell structured Cu@Au nanoparticles. The resulting photoelectrode, termed Cu@Au/SiNW, shows improved selectivity toward CO production and gives a good Faradic efficiency of 72% in an aqueous medium.

Facile preparation of anti-biofouling reverse osmosis membrane embedded with polydopamine-nano copper functionality: Performance and mechanism

In this study, we conducted a facile membrane modification process by mild electroless deposition of copper nanoparticles (CuNPs) integrating polydopamine (PDA) coating to combat biofouling of thin-film composite (TFC) reverse osmosis (RO) membranes. Various experimental tests and characterization techniques have been applied to reveal the anti-biofouling performance and underlying mechanism of prepared membranes (i.e., Cu/PDA/TFC membrane). The successful functionalization with PDA and CuNPs highly enhanced the anti-fouling properties of Cu/PDA/TFC membrane, as evidenced by 45%, 40% and 37% respectively lower adsorption of bovine serum albumin, humic acid, and lipopolysaccharide in static adhesion assays. A significant decreased membrane-foulant adhesion forces by 63% was observed for Cu/PDA/TFC membrane compared to control membrane, which is ascribed to enhanced membrane surface hydrophilicity after PDA coating. Moreover, The Cu/PDA/TFC membranes presented significantly decreased cell viability (E. coli from 90% to 22%, P. aeruginosa from 89% to 26%, and S. aureus from 84% to 18%), and reduced adenosine tri-phosphate (ATP) content after 3 h bacterial exposure (E. coli by 57%, P. aeruginosa by 50%, and S. aureus by 56%). Assessment on cell viability and metabolic activities of bacteria deposited on membrane indicate that contact-mediated toxicity contributed to the antibacterial mechanism of Cu/PDA//TFC membrane. In addition, the reduced viability of the planktonic cells at the membrane surroundings under durable copper leaching (∼17 mg/m2 to ∼9 mg/m2) suggest that release of antibacterial Cu2+ ions also played an important role in membrane antibacterial mechanism. Both contact-mediated and Cu2+ release-based antibacterial mechanisms endow Cu/PDA/TFC membrane with excellent anti-biofouling capacity under long-term dynamic condition, with 45% lower flux decline compared to the control membrane.

Optimisation of Operational Parameters in Atmospheric Plasma Deposition

Nowadays additive manufacturing and 3D printing techniques are transferring in the mainstream industrial use. To compete for the share of the pie in this sector, atmospheric plasma can be used for deposition of material. In this work it will be presented the atmospheric plasma deposition of copper nanoparticles and the influence of the plasma operational parameters on the shape of the deposited copper line: the with and the density. The nanoparticles were produced by a facile aqueous-based seed-mediated chemical reduction method from copper nitrate hemi(pentahydrate), as described in article by Ankireddy et al. 1 The copper nanoparticles had bimodal size distribution with mean diameters of 3.6 and 64.6 nm. The nanoparticles were then dispersed in deionised water, caped with citric acid and used as a source for atmospheric plasma deposition. The plasma system comprised from nebuliser, nozzle and kHz power supply, as in the work of Gandhiraman et al. 2 During the plasma deposition of the particles the substrate was moving by XY step-motor stage. Parameters, that could be set and influenced the deposition were: gas mixture (different ratios of Ar and He gas flows), gas flow-rate, distance of the substrate from the plasma, plasma power, time between steps of XY stage and the number of passes/repetitions by XY stage. Different permutations of the parameters were used for the plasma deposition to determine the best parameter set for a dense deposition of a narrow line.In figure it can be seen two depositions with different parameters. The difference is obvious.[1] „Seed Mediated Copper Nanoparticle Synthesis for Fabricating Oxidation Free Interdigitated Electrodes using Intense Pulse Light Sintering for Flexible Printed Chemical Sensors“; Krishnamraju Ankireddy, Thad Druffel, Swathi Vunnam, Gregor Filipič, Ruvini Dharmadasa, Delaina A. Amos; Journal of Materials Chemistry C, 5 (2017), 11128 – 11137[2] „Plasma jet based in situ reduction of copper oxide in direct write printing“; Avishek Dey, Arlene Lopez, Gregor Filipič, Aditya Jayan, Dennis Nordlund, Jessica Koehne, Satheesh Krishnamurthy, Ram P. Gandhiraman, M. Meyyappan; Journal of Vacuum Science & Technology B, 37 (2019), 031203 Figure 1

Fabrication of Conductive and Gas-Sensing Microstructures Using Focused Deposition of Copper Nanoparticles Synthesized by Spark Discharge

Solvent-free aerosol jet printing has been investigated for fabricating metallic and semiconductor (gas-sensitive) microstructures based on copper nanoparticles on alumina, borosilicate glass, and silicon substrates. The synthesis of nanoparticles was carried out using a spark discharge directly in the printing process without the stage of preparing nano-ink. Printed lines with a width of 100–150 µm and a height of 5–7 µm were formed from submicron agglomerates consisting of primary nanoparticles 10.8 ± 4.9 nm in size with an amorphous oxide shell. The electrical resistivity, surface morphology, and shrinkage of printed lines were investigated depending on the reduction sintering temperature. Sintering of copper oxides of nanoparticles began at a temperature of 450 °C in a hydrogen atmosphere with shrinkage at the level of 45–60%. Moreover, aerosol heat treatment was used to obtain highly conductive lines by increasing the packing density of deposited nanoparticles, providing in-situ transformation of submicron agglomerates into spherical nanoparticles with a size of 20–50 nm. Copper lines of spherical nanoparticles demonstrated excellent resistivity at 5 μΩ·cm, about three times higher than that of bulk copper. In turn, semiconductor microstructures based on unsintered agglomerates of oxidized copper have a fairly high sensitivity to NH3 and CO. Values of response of the sensor based on non-sintered oxidized copper nanoparticles to ammonia and carbon monoxide concentration of 40 ppm were about 20% and 80%, respectively.

Emerging investigator series: prompt response of estuarine denitrifying bacterial communities to copper nanoparticles at relevant environmental concentrations

In estuaries the deposition of copper nanoparticles upon sediments can contribute to change metal availability and promote the transcriptional response of denitrifying bacteria.

Effect of carbon support on the catalytic activity of copper-based catalyst in CO2 electroreduction

Climate change caused by carbon dioxide anthropogenic emissions has turned into one of the most important environmental concerns of our society. Among the different actions proposed for mitigation of CO2 emissions, electrocatalytic reduction appears as a very promising technology for recycling CO2 to synthetic fuels and other valuable products. One of the most important challenges of this technology is the development of catalysts that allow obtaining high efficiencies in the reduction of the CO2 molecule. This work is focused in the development of Cu based nanostructured catalysts deposited on carbon supports. Supercritical fluid deposition (SFD) technique has been used for the copper deposition on three different carbon supports: carbon black (CB), carbon nanotubes (CNT) and reduced graphene oxide (rGO). SFD is an environmentally friendly technology that has demonstrated good results in the synthesis of nanomaterials.Results obtained in this work show that SFD technique allows a homogeneous deposition of copper nanoparticles on the different carbon supports used with deposition yields close to 90%. The average size of copper nanoparticles formed is between 13 and 19 nm.The activity of these catalysts (Cu/CB, Cu/CNT and Cu/rGO) in the electrocatalytic reduction of carbon dioxide has been carried out in gas phase in a PEM type electrochemical cell. Results show a higher CO2 conversion rate (around 40%) when using Cu/CNT catalyst. In every case, CO, formic acid and methane are the main reaction products obtained from the CO2 reduction. Nevertheless, Cu/CNT and Cu/CB catalysts promote the formation of CO, whereas formic acid is the main reaction product with Cu/rGO. This could be attributed to the presence of oxygenated groups observed in the rGO based catalyst. These results point out that the interaction between the copper nanoparticles and the carbon support plays an important role in the CO2 electrocatalytic reduction process.

Synthesis, characterization, toxicological and antibacterial activity evaluation of Cu@ZnO nanocomposites

Abstract Cu@ZnO is an important class of material with applications as catalysts, photocatalysts, optoelectronic devices and antimicrobial agents. Because of its potential for large-scale applications and its high redox activity, detailed examination of the properties and risk assessment of this class of materials should be performed. In this work, Cu@ZnO composites were synthesized using a two-step procedure. ZnO crystalline nanostructured materials were prepared within minutes by a solvothermal microwave-assisted method. Deposition of copper nanoparticles on the surface of ZnO was conducted by reduction of Cu2+ in ethylene glycol (EG). Copper nanoparticles with different morphologies (needle-like and spheres) were deposited on the surface of ZnO. The antibacterial activity of Cu@ZnO composites was evaluated using E. coli and S. aureus as model organisms. The Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC) were evaluated for Cu@ZnO composites under visible light radiation (VLR) and in the dark (D). The composites exhibit antibacterial activity under VLR at low concentrations: 250 μg/mL and 750 μg/mL for E. coli, and 250 μg/mL and 500 μg/mL for S. aureus. Copper nanoparticles exert antibacterial activity and can be used to inhibit the growth of microorganisms in the absence of irradiation of Cu@ZnO material. Better antibacterial activity of Cu@ZnO material was achieved under radiation, demonstrating the synergic activity of Cu and ZnO materials for disinfection. Toxicity of the material was assessed towards Daphnia magna (D. magna) and Lecane papuana (L. papuana). Composites exert toxicity at lower concentrations than ZnO, observing LC50 values for L. papuana of 79.30 ± 6.70 μg/mL, and 5.59 ± 0.46 μg/mL for ZnO and Cu@ZnO, respectively. For D. magna, a LC50 of 9.66 ± 1.22 μg/mL (Cu@ZnO) was observed. Although Cu@ZnO can be considered as potential candidate for the development of efficient antibacterial agents, its antibacterial activity is achieved at doses that can be harmful to aquatic invertebrates. Thus, its application should avoid its entry to aquatic environments.

Fabrication of Flexible and Superhydrophobic Melamine Sponge with Aligned Copper Nanoparticle Coating for Self-Cleaning and Dual Thermal Management Properties

In this work, a three-dimensional (3D) flexible copper coated melamine sponge (Cu-MES) with superhydrophobic properties capable of active heating and infrared insulation is fabricated via deposition of copper nanoparticles on the MES surfaces for personal thermal management applications. The results showed that the Cu nanoparticles were tightly anchored on the surface of the melamine sponge, forming a low infrared emissivity coating, resulting in high thermal insulation properties of the multifunctional Cu-MES. The promising electrical conductivity grants the superior Joule heating for extra warmth of 40 °C using a low supply voltage around 7 V. Besides, obtained Cu-MES material shows a self-cleaning property with a stable water contact angle of 157.5° and a sliding angle of 15°. These promising results including low infrared emissivity for high thermal insulation and high conductivity for heat collection make the Cu-MES promising candidates for applications in personal thermal management, energy regulation, and other facilities.

A highly conductive, pliable and foldable Cu/cellulose paper electrode enabled by controlled deposition of copper nanoparticles.

There is great interest in extending cellulosic platforms to applications in flexible, lightweight, low-cost and sustainable electronics. The critical need is the development of methods to confer electronic properties to these materials platforms (i.e., paper and fabrics). Here we report a highly conductive, pliable and foldable Cu/cellulose paper electrode enabled by a simple low-cost and scalable wet-processing method to coat a Cu nanoparticle (NP) layer on common cellulose paper, where polydopamine adhesion and electroless deposition were used to yield highly conductive paper with a sheet resistance as low as 0.01 Ω sq-1. This Cu/cellulose paper has excellent stability because of the strong adhesion between Cu NPs and cellulose, and because the methods are sufficiently mild to prevent damage to the paper substrate. This fabrication method results in the controlled deposition of Cu NPs and yields Cu/cellulose paper with highly hydrophobic and self-cleaning properties, high photothermal conversion efficiency, and excellent electromagnetic interface (EMI) shielding effectiveness. This high-performance Cu/cellulose paper could have promising application potential for a range of emerging applications in flexible electronics and packaging.

Silver/Silicon nanowires/copper nanoparticles heterojunction for methyl orange degradation by heterogeneous photocatalysis under visible irradiation

ABSTRACTIn this work, the degradation of methyl orange (MO) was analyzed by direct light with visible radiation (λ > 450 nm) of a dye solution in the presence of silicon nanowires (SiNWs) or silicon nanowires with copper nanoparticles (SiNWs-CuNPs). The SiNWs were synthesized by metal assisted etching from monocrystalline silicon wafers in aqueous HF / AgNO3 solution, and the CuNPs were deposited on the SiNWs via electroless. Discoloration with visible irradiation of aqueous methyl orange solution (C14H14N3NaOS) in the presence of SiNWs showed an efficiency of 71% after 120 min of illumination. The deposition of copper nanoparticles on the nanowires improves the efficiency of the photocatalytic reaction achieving 89% discoloration after 120 min exposure to visible light. The MO photocatalytic degradation with visible radiation in aqueous solution shows to be efficient in discoloration reaching up to 92% in a time of 150 min in the presence of SiNWs-CuNPs.

Ultrafine copper decorated polypyrrole nanotube electrode for nitrite detection

In this report, a nitrite electrochemical sensor was developed by electrochemical deposition of copper nanoparticles on the polypyrrole nanotubes (PPy-Cu). The PPy nanotubes were synthesized via pyrrole polymerization on electrospun polystyrene nanofibers (PS) with the diameter of 150 nm, followed by PS removal. The prepared nanotubes were characterized using Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Ultrafine Cu nanoparticles with the size of 4.2 ± 1.2 nm were uniformly deposited on PPy tubes by electrolysis. The existence of zero valence Cu particles was demonstrated by transmission electron microscopy (TEM) and X-ray photo spectroscopy (XPS). The electrochemical behaviors of the PPy and PPy-Cu electrodes were investigated by cyclic voltammetry (CV). PPy enhances the deposition of Cu dramatically and facilitates the uniform distribution of the copper nanoparticles. The obtained PPy-Cu exhibits an excellent catalytic activity to the reduction of nitrite. The catalytic performance of the resultant PPy-Cu electrodes was optimized by varying the PPy morphology and Cu deposition amount. Using hydrodynamic current-time curves, the linear relationship was obtained, under the optimized conditions, in the range of 0.1 μM to 1 mM with a limit of detection of 0.03 μM (S/N > 3). The sensor presents good reproducibility and stability for nitrite determination.

Nanoparticles based on copper deposited on carbon spheres. Preparation, characterization and application for CO2 photo-electrochemical reduction

In this study, we have examined the performance of copper nanoparticles deposited on carbon spheres with a mass weigh of 10wt% (labeled 10Cu-CSs) via photo-electrochemical reduction of carbon dioxide (CO2). The carbon spheres (CSs) were prepared by a chemical vapor deposition method and 10Cu-CSs was made via a homogeneous deposition precipitation method. The materials were characterized by different physico-chemical techniques such as X-ray diffraction (XRD), Raman, Fourier transform infrared (FTIR) and diffuse reflectance (DR) spectroscopy, electrical conductivity and photo-electrochemical studies. The 10Cu-CSs material was studied for the photo-electrochemical reduction of CO2 under visible light illumination. The synthesized material exhibited a single phase monoclinic structure of CuO deposited on CSs as confirmed by XRD, Raman and FTIR spectroscopies results. The semi-conductor property was established by electrical conductivity, and the activation energy obtained was ca. 0.04eV. The UV–visible absorption spectrum showed a direct band gap transition with gap energy of 1.22eV. The material synthesized was a cathode semi-conductor with p-type conductivity. The deposition of copper nanoparticles enhanced the CO2 photo-conversion to formic acid under the reaction conditions. In particular, 10Cu-CSs demonstrated gave formic acid, which was at a higher potential than standard redox potentials of copper. Furthermore, the photo-electrochemical characterization showed that the deposition of the copper onto CSs used as electrode effectively generated photo-induced electron/hole pairs under visible light irradiation leading an enhancement of photo-reduction under visible light in a NaHCO3 electrolyte.

Possible roles of uterine PGRMC1 in the implantation and decidualization

In this study, we have examined the performance of copper nanoparticles deposited on carbon spheres with a mass weigh of 10 wt% (labeled 10Cu-CSs) via photo-electrochemical reduction of carbon dioxide (CO2). The carbon spheres (CSs) were prepared by a chemical vapor deposition method and 10Cu-CSs was made via a homogeneous deposition precipitation method. The materials were characterized by different physico-chemical techniques such as X-ray diffraction (XRD), Raman, Fourier transform infrared (FTIR) and diffuse reflectance (DR) spectroscopy, electrical conductivity and photo-electrochemical studies. The 10Cu-CSs material was studied for the photo-electrochemical reduction of CO2 under visible light illumination. The synthesized material exhibited a single phase monoclinic structure of CuO deposited on CSs as confirmed by XRD, Raman and FTIR spectroscopies results. The semi-conductor property was established by electrical conductivity, and the activation energy obtained was ca. 0.04 eV. The UV–visible absorption spectrum showed a direct band gap transition with gap energy of 1.22 eV. The material synthesized was a cathode semi-conductor with p-type conductivity. The deposition of copper nanoparticles enhanced the CO2 photo-conversion to formic acid under the reaction conditions. In particular, 10Cu-CSs demonstrated gave formic acid, which was at a higher potential than standard redox potentials of copper. Furthermore, the photo-electrochemical characterization showed that the deposition of the copper onto CSs used as electrode effectively generated photo-induced electron/hole pairs under visible light irradiation leading an enhancement of photo-reduction under visible light in a NaHCO3 electrolyte.

Facile one-step electrochemical deposition of copper nanoparticles and reduced graphene oxide as nonenzymatic hydrogen peroxide sensor

For several decades, hydrogen peroxide has exhibited to be an extremely significant analyte as an intermediate in several biological devices as well as in many industrial systems. A straightforward and novel one-step technique was employed to develop a sensitive non-enzymatic hydrogen peroxide (H2O2) sensor by simultaneous electrodeposition of copper nanoparticles (CuNPs) and reduced graphene oxide (rGO). The electroreduction performance of the CuNPs-rGO for hydrogen peroxide detection was studied by cyclic voltammetry (CV) and chronoamperometry (AMP) methods The CuNPs-rGO showed a synergistic effect of reduced graphene oxide and copper nanoparticles towards the electroreduction of hydrogen peroxide, indicating high reduction current. At detection potential of −0.2V, the CuNPs-rGO sensor demonstrated a wide linear range up to 18mM with a detection limit of 0.601 mM (S/N=3). Furthermore, with addition of hydrogen peroxide, the sensor responded very quickly (<3s). The CuNPs-rGO presents high selectivity, sensitivity, stability and fast amperometric sensing towards hydrogen peroxide which makes it favorable for the development of non-enzymatic hydrogen peroxide sensor.

Decoration of Copper Nanoparticles on Multiwalled Carbon Nanotubes and the Study of Electrocatalytic Activity for Methanol Oxidation

The decoration of Copper Nanoparticles on Multiwalled carbon nanotubes (MWCNTs) and the study of electrocatalytic activity of these Cu/MWCNTs for methanol oxidation have been investigated. In the process, the activated MWCNTs were used as substrate precursor. The morphology of MWCNTs after Copper Nanoparticle decoration was characterized by High-resolution transmission electron microscope (HRTEM). The X-ray diffraction (XRD) patterns have shown the Copper deposition on MWCNTs. The extent of deposition of Copper Nanoparticles on MWCNTs including the under coat elements such as Tin and Palladium is obtained by Energy dispersive X-ray analysis (EDX) and X-Ray Photoelectron Spectroscopy (XPES). A significant electrocatalytic activity of Cu/MWCNTs for the oxidation of methanol was found by Cyclic Voltammetry and Electrochemical Impendence spectroscopic (EIS) studies.

Electrodeposited copper nanoparticles: plasmon enhanced performance of TiO2 for dye sensitized solar cell

The Copper being cheap and more abundant in nature is being utilized on a large scale as an energy harvester. The present work is carried out on studies of the plasmonic effect of copper nanoparticles in dyesensitized solar cells. The copper nanoparticles were electrochemically deposited from an aqueous solution of copper sulphate on TiO2 film coated on flourine doped tin oxide (FTO). The film was kept in an aqueous “Rose Bengal” dye before and after deposition of copper nanoparticles. The incorporation of copper nanoparticles enhanced the overall power conversion efficiency of the dye sensitized solar cell. This enhancement is manifested chiefly due to increased dye loading and strongly absorbed light due to localized surface plasmon resonance of incorporated Cu nanoparticles in dye sensitized solar cell.

Radiation induced deposition of copper nanoparticles inside the nanochannels of poly(acrylic acid)-grafted poly(ethylene terephthalate) track-etched membranes

Poly(ethylene terephthalate) PET, track-etched membranes (TeMs) with 400nm average pore size were UV-grafted with poly(acrylic acid) (PAA) after oxidation of inner surfaces by H2O2/UV system. Carboxylate groups of grafted PAA chains were easily complexed with Cu2+ ions in aqueous solutions. These ions were converted into metallic copper nanoparticles (NPs) by radiation-induced reduction of copper ions in aqueous-alcohol solution by gamma rays in the dose range of 46–250kGy. Copper ions chelating with -COOH groups of PAA chains grafted on PET TeMs form polymer-metal ion complex that prevent the formation of agglomerates during reduction of copper ions to metallic nanoparticles. The detailed analysis by X-Ray diffraction technique (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) confirmed the deposition of copper nanoparticles with the average size of 70nm on the inner surface of nanochannels of PET TeMs. Samples were also investigated by FTIR, ESR spectroscopies to follow copper ion reduction.