Increasing CuO Content Research Articles

Structure and gamma attenuation behavior of copper ions in host glass from the system (P2O5–LiF–CaF2)

Copper-doped lithium calcium fluorophosphate glasses in the compositional system (60−x)P2O5·20LiF·20CaF2·xCuO (x = 0−3 mol%) were prepared using the conventional melt quenching technique. X-ray diffraction confirmed the amorphous, non-crystalline phase of the glasses. Optical absorption spectra indicated the presence of additional broad visible-NIR absorption bands upon CuO doping, attributed to distorted Cu2+ ions. Possible overlaps from Jahn-Teller distorted sites or clustering into nanodomains may contribute to band broadening. The direct optical bandgap was found to reduce from 3.89 eV to 1.17 eV with increasing CuO content. The study of physical parameters showed almost linear variation in density (2.62–2.95 g/cm3) and molar volume (40.45–35.29 cm3/mol) with incremental CuO substitution, explained by changes in structural packing efficiency and formation of Cu–O complexes. FTIR spectra revealed vibrations corresponding to phosphate structural groups. The simulation of radiation shielding parameters displayed steady improvements with higher CuO fractions, which were related to enhanced photon interactions via photoelectric absorption and Compton scattering.

Effects of different mass ratios on mechanical properties and impact energy release characteristics of Al/PTFE/W and Al/PTFE/CuO polymer composites

AbstractAluminum/polytetrafluoroethylene (Al/PTFE) is an impact‐initiated material that is extensively utilized in military and civilian applications due to its insensitivity, high energy density and ease of manufacturing. To increase both its compressive strength and energy density, Al/PTFE was doped with various amounts of W and CuO particles. These polymer composites exhibit elastoplastic properties, as well as significant strain hardening and strain‐rate hardening during compression deformation. At a strain rate of 5000 s−1, the compressive strength of the Al/PTFE/W and Al/PTFE/CuO specimens with an additive content of 30% reaches a peak of 194.1 and 189.2 MPa, which corresponds to an increase of 40.3% and 36.8%, respectively, compared with the compressive strength of Al/PTFE (138.3 MPa). The homogeneous bonding strength between the additives and PTFE and the fact that the elastic PTFE nanofibers inhibit the extension of microcracks are the main mechanical strengthening mechanisms. The reaction of the composites under high‐speed impact is violent and accompanied by sputtering sparks, and the reaction efficiency was determined using an improved drop‐hammer apparatus. As the W content increases, the impact reactivity of Al/PTFE/W decreases monotonically. However, as CuO content increases, the reaction intensity of Al/PTFE/CuO initially increases, and then decreases. At a CuO content of 30%, the energy release efficiency of Al/PTFE/CuO reaches its maximum (10.49%), which is 84.4% higher than that of Al/PTFE. TG‐DSC and XRD tests were performed to analyze the pyrolysis process and elucidate the reaction mechanism. A gas–solid chemical reaction model was developed, and the reactivity arises from multiple factors.Highlights Typical elastoplastic characteristics as well as strain hardening and strain‐rate hardening were observed. The mechanical strengthening effect of W particles is higher than that of CuO particles of Al/PTFE specimen. The addition of W particles decreases the impact reactivity, but the addition of CuO particles improves the energy density of Al/PTFE. The reaction efficiency of Al/PTFE/CuO reaches a peak of 10.49%, which increased by 84.4% compared with that of Al/PTFE.

Physical properties and Raman spectroscopy inquiry of copper laden bio-relevant calcium phosphate glasses and the exposed to γ-irradiation

Pristine bio-relevant glasses of the P2O5-CaO-Na2O-CuO type where the [CuO]/[Na2O] molar ratios were varied at about 0.1, 0.7 and 1.5 have been scrutinized concerning fundamental physical properties and Raman spectroscopic features. Interpretations were assisted by X-ray photoelectron spectroscopy results regarding the chemical environments of oxygen, phosphorus, and copper. X-ray diffraction measurements performed using Mo-Kα radiation as X-ray source confirmed the amorphous character of the glasses, whereas differential scanning calorimetry showed rising glass transition temperatures with increasing copper content. The densities of the glasses increased linearly with CuO concentration whereas the molar volumes and phosphorus-phosphorus mean distances decreased. Raman results showed variation in the intensities, positions, and widths of main bands with increasing CuO concentration which was attributed to the impact of copper ions with high ionic field strength rather than a depolymerization effect. Finally, the Raman spectroscopy evaluation was extended to γ-irradiated (100 kGy) counterparts for a comparison with the pristine glasses. The γ-irradiated glasses however did not show significant changes in the Raman spectra thus supporting a lack of structural variation after the exposure to the ionizing radiation.

Effect of high CuO additive on the properties of Nickel-zinc ferrite for near field communication

In this work, Nickel-zinc ferrite materials with 6 %～10 % high CuO mass content were prepared below 961 °C by a traditional metal oxide ceramic sintering process, which includes powder mixing, presintering, ball-milling, granulation and sintering. The effect of high CuO mass content on the electromagnetic properties of Nickel-zinc ferrite was studied. The results show that all the samples present a spinel structure without impurities. With the increase of CuO content from 6 % to 10 %, the hysteresis loops change visibly in wideness and height, in which Bs (Saturation magnetic induction) = 350 ∼ 400mT, Br(Remanent magnetic induction) = 240 ∼ 300mT, Hc (Coercivity) = 110 ∼ 200 A/m and the shrinkage of the sintered sample increases from 113.9 % to 115.8 %, the density boosts from 4.81 g/cm3 to 5.05 g/cm3 and Tc (Curie temperature) increases from 175 °C to 260 °C. The impedance of the sample at low frequency has no obvious relationship with the CuO mass content, but the impedance of Nickel-zinc ferrite with high CuO content is about 65 Ω bigger than that of the samples with low CuO content when the frequency is above 500 MHz. Pcv(Core loss) reaches the highest value when the CuO mass content is 9 %. For the sample with 8 % CuO, the magnetic loss is minimum and the cut-off frequency is maximum, being 5.7 and 20.56 MHz, respectively.

Effects of CuO additive on properties of high-performance (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 piezoceramics obtained by vat photopolymerization

Lead-free (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 (BCZT) piezoelectric ceramics are ideal materials for the preparation of piezoelectric ceramic devices. However, pure BCZT ceramics have the problems of high sintering temperature and unsatisfactory Curie temperature. Besides, piezoelectric ceramic devices with complex structures are difficult to fabricate with conventional processing methods. In this paper, we prepared BCZT ceramics with CuO additions of 0, 0.5, 1.0, 1.5, and 2.0 mol% based on vat photopolymerization, and investigated effects of CuO additive on their various properties. The appropriate addition of CuO greatly improved the piezoelectric properties and lowered the sintering temperature by 100 °C. With increasing CuO content, it was found that the phase composition shifted from an orthogonal phase to the coexistence of orthogonal and tetragonal phases. BCZT-1.5 mol%CuO sintered at 1400 °C exhibited the best performance: d33 = 525 pC/N，g33 = 13.7 × 10−3 Vm/N，εr = 4323，tan δ = 0.012，Pr = 14.66 μC/cm2，Ec = 2.42 kV/cm. In addition, when the energy harvesting performance of BCZT-1.5 mol%CuO with complex structures prepared by vat photopolymerization was tested, the short circuit current (Isc) and open circuit voltage (Voc) of BCZT-1.5 mol% CuO ceramics were ∼13.0 pA and ∼11.0 mV, respectively, which exhibited better energy harvesting capability than the pure BCZT ceramics. These results suggest that the performance of BCZT ceramics can be significantly enhanced with CuO additive and verify the feasibility of vat photopolymerization forming high-performance piezoelectric ceramics with complex structures.

Effect of CuO addition on the structural, electrical and dielectric properties of the sodium borate glasses

The sodium borate glasses doped with different CuO content (70B2O3˗30Na2O˗xCuO with x = 0, 2, 4, 6 and 8 mol%) have been prepared using the conventional melt-quenching technique. The amorphous nature of the prepared samples has been identified by X-ray diffraction (XRD). The experimental and theoretical density, the molar volume, and the oxygen packing density have been defined. The effect of CuO incorporation into the 70B2O3˗30Na2O glass base on the electrical and dielectric properties has been studied. The D.C. electrical parameters have been measured in the temperature range 323˗483 K, while the dielectric parameters have been measured in the temperature range 333˗483 K and the frequency range 10−1˗ 107 Hz. The D.C. electrical conductivity increases while the activation energy decreases by increasing CuO content (mol%). The conduction type is ionic which CuO inserts into the glass structure as a glass modifier. The A.C. study reveals that all investigated glasses obey the correlated barrier hopping model (CBH). Moreover, the dissipation factor peaks indicate the glasses' relaxation nature which has been further analyzed from the real and imaginary parts of the electric modulus.

Modeling and optical characterization of γ-irradiated Cu2+Doped borate glasses as bandpass optical filters

Novel systems of alkali borate glasses with various CuO concentrations from 0.2 up to 1.5 mol% have been prepared by the conventional melt-quenching technique. Several optical, physical, and structural characteristics of the prepared glasses have been examined before and after incremental γ-irradiation doses. The intensity of the blue color of the glasses is controlled by CuO concentrations, with Cu+/Cu2+ in ionic equilibrium. UV/Vis absorption peaks centered at 740 nm can be correlated to a tetragonal twist of the octahedral structure due to 2B1g-2B2g electronic transition. Photoluminescence (PL) extinction spectra can be attributed to Cu+-Cu+ energy migration after Cu+→ Cu2+ energy transfer. Electron spin resonance (ESR) measurements show sharp signals at magnetic fields ranging from 3344 to 3326 Gauss (g = 2.08–2.09), corresponding to the divalent copper state (Cu2+) in octahedral units. FTIR spectra revealed stable structures towards irradiation. Either an increase in CuO content or irradiation led to greater UV absorption, lower PL intensity, lower bandgap (Eopt), lower density, larger molar volume, and slightly more intense ESR signals. Copper ions can be considered as modifiers since they increase the degree of disorder in the glassy network. UV/NIR band stop, FWHM, and center of peaks confirmed the high efficiency of the prepared Cu-doped glasses as colored optical bandpass filters in the green and near-blue regions for UV/IR light laser protection.

Impact of CuO loading for enhanced photocatalytic performance of CdS/CuO photocatalyst on rhodamine 6G dye decomposition under ultraviolet irradiation

In this study, we have incorporated different ratios of copper oxide (CuO) into cadmium sulphide (CdS) to fabricate CdS/CuO binary composites that are utilized as an efficient photocatalyst for rhodamine 6G (R6G) dye decomposition under ultraviolet (UV) exposure. CdS and CuO formed by precipitation and annealing were combined to form composites using a wet physical mixing method. X-ray diffraction (XRD) analysis reveals the preservation of their respective crystalline phases in the composite. Scanning electron microscopy (SEM) images imply that the interface between CuO and CdS improves with increasing CuO content. The coexistence of CuO and CdS compounds could also be verified by Fourier-transform infrared spectroscopy (FTIR) analysis. Also, the UV–Vis absorbance spectra demonstrate a significant increase in absorption intensity accompanied by a bandgap narrowing, which is beneficial for photocatalytic activity. The photocatalytic degradation rate and efficiency are significantly enhanced with CuO loading, with the highest constant rate obtained being as 4.69 × 10-3 min−1. Conclusively, the present CdS/CuO composite can serve as a vital catalyst for environmental sustainability, especially in wastewater remediation.

Structural and UV-blocking properties of carboxymethyl cellulose sodium/CuO nanocomposite films

Nanoparticles have made a substantial contribution to the field of skincare products with UV filters in preserving human skin from sun damage. The current study aims to create new polymer nanocomposite filters for the efficient block of UV light that results from the stratospheric ozone layer loss. The casting approach was used to add various mass fractions of copper oxide nanoparticles (CuO-NPs) to a solution of carboxymethyl cellulose (CMC). The amorphous nature of CMC was revealed by XRD analysis, with the intensity of the typical peak of virgin polymer in the nanocomposite spectrum decreasing dramatically as the doping amount was increased. The FTIR spectra revealed the functional groups of CMC and the good interaction between the CMC chain and CuO-NPs. Optical experiments revealed that the optical transmittance of pure CMC was over 80%, whereas it dropped to 1% when CuO-NPs content was increased to 8 wt.%. Surprisingly, the inclusion of CuO-NPs considerably improved the UV blocking property of the films extended from the UV region (both UV-A: 320–400 nm and UV-B: 280–320 nm) to the visible region. Optical band gap of CMC decreased sharply with increasing CuO concentration. The tunable optical characteristics can be utilized in UV- blocking filters and various optoelectronics applications.

Thermoelectric properties of solid state reaction-prepared ZnO based alloys with various CuO doping in (CuO)x(ZnO)1−x

Thermoelectric (TE) materials based on ZnO and CuO materials in the form (CuO)x (ZnO)1−x were prepared via a solid state reaction method. The structure of the samples was analyzed using X-ray diffraction (XRD), where observed to be polycrystalline and monoclinic in structure. The nanostructure of the samples was characterized by scanning electron microscopy (SEM). By increasing CuO concentration, the surface morphologies of the samples were changed from a layered shape and well-packed structures to a uniform large grain distribution. Increases in CuO caused an increase in hole concentration (p) and electrical conductivity (σ), whereas, a comparatively decrease in Seebeck coefficient (S). A higher power factor (S2σ) of 12.92 μW/mK2 was obtained at about 575 K for a CuO0·75ZnO0.25 sample (x = 0.75).

Effect of CuO Nanoparticle on Ceratophyllum demersum

In this study, it was aimed to determine some physiological effects of CuO nanoparticle on C. demersum. The plants were collected from an uncontaminated pond in Gaziantep province. Different concentrations of CuO (0, 25, 50, 100 and 200 mg/L) were applied to the macrophytes after being acclimatized in controlled conditions. Some analyses were made on macrophytes harvested at the end of the application. The contents of protein, total carbohydrate, photosynthetic pigment, total phenolic compound, non-protein sulfhydryl groups of tissues increased with increasing CuO concentration under the influence of applied CuO concentrations. In addition, increases in hydrogen peroxide and MDA contents were also detected. As a result, it was determined that the applied CuO concentrations caused some physiological changes in C. demersum tissues.

The effects of CuO doping on structural, electrical and optical properties of CdO thin films deposited by pulsed laser deposition technique

Thin films of (CdO)x (CuO)1-x (where x = 0.0, 0.2, 0.3, 0.4 and 0.5) were prepared by the pulsed laser deposition. The CuO addition caused an increase in diffraction peaks intensity at (111) and a decrease in diffraction peaks intensity at (200). As CuO content increases, the band gap increases to a maximum of 3.51 eV, maximum resistivity of 8.251x 104 Ω.cm with mobility of 199.5 cm2 / V.s, when x= 0.5. The results show that the conductivity is ntype when x value was changed in the range (0 to 0.4) but further addition of CuO converted the samples to p-type.

Study of ignition and combustion characteristics of kerosene-based nanofluid fuel containing n-Al/CuO thermite

The ignition and combustion properties of n-Al/CuO/kerosene nanofluid fuels are examined, with a focus on the formulation effects of the n-Al/CuO nano-thermite. The DSC data shows the addition of CuO facilitates the exothermic process of n-Al particles, which then promote the n-Al/CuO/kerosene droplets to evaporate. There are two exothermic peaks on the DSC curve of n-Al/CuO (5 %) at 249.3 ℃ and 463.8 ℃, respectively. The burning of n-Al/CuO/kerosene droplets consists of four stages: ignition, d2-law combustion, vapor flame extinguishment, and agglomerate burning. During the agglomerate burning stage, n-Al/CuO (5 %)/kerosene shows the minimum ignition delay at 0.057 s and the highest emission spectral intensity. Droplet combustion conforms well to the d2-law, and the maximum combustion rate is found for n-Al/CuO (20 %)/kerosene, at 1.287 mm2 s−1. The particle size of combustion residues is uniform, and the overall appearance smoothens as the CuO content increases. A new nanofluid fuel with better ignition and combustion properties than traditional nanofluid fuels is proposed.

Dielectric and impedance studies of binary ZnO–CuO nanocomposites for hydroelectric cell application

Nanocomposites of xZnO-(1-x)CuO (x = 0.39, 0.69, 0.85) were synthesized using conventional solid state reaction method. The structural, dielectric and impedance properties of ZnO–CuO nanocomposites have been comprehensively studied. The X-ray diffraction studies show that the crystallite size decreases from 47 nm to 35 nm from 0.85ZnO-0.15CuO to 0.39ZnO-0.61CuO along with lowering of lattice parameter of ZnO–CuO on account of improved crystallinity. The UV–Vis spectroscopy display increase in bandgap with increasing CuO content in the nanocomposites. The dielectric constant in ZnO–CuO nanocomposites is found to improve strongly with CuO content in ZnO–CuO nanocomposites and apprise existence of non-Debye relaxation process. The dielectric loss decreases from 10 to nearly unit value due to increased crystallinity. The impedance spectroscopy analysis indicated the dielectric relaxation to be of poly-dispersive non-Debye type with dominant grain boundary contribution in the ZnO–CuO nanocomposite. The hydroelectric cells of ZnO–CuO nanocomposites exhibited enhanced performance with CuO content on account of improved ionic diffusion. The 0.69ZnO-0,31CuO nanocomposites displayed a constant current of 0.46 mA sustained for up to 3 h. These results make ZnO–CuO nanocomposites suitable for microelectronic and hydroelectric cell applications.

Sm3+ photoluminescence and excited-state dynamics in lithium-barium borate glasses co-doped with CuO

• Lithium-barium borate glasses containing Sm 2 O 3 and CuO prepared by melting. • Characterizations performed by XRD, FT-IR, UV/Vis/NIR and photoluminescence spectroscopies. • Influence of CuO on Sm 3+ luminescence investigated through PL decay kinetics. • Efficient Sm 3+ → Cu 2+ energy transfer indicated due to strong spectral overlap. The effect of CuO co-doping on orange/red-emitting Sm 3+ -doped borate glasses prepared by melting was investigated by various spectroscopic techniques. The glasses were first characterized by X-ray diffraction and Fourier transform-infrared spectroscopy for basic structural properties. Absorption spectroscopy showed that CuO addition leads to the development of the Cu 2+ absorption band around 735 nm. Photoluminescence (PL) spectra obtained for the CuO-free reference glass under 250 nm excitation displayed host-sensitized Sm 3+ PL along with intrinsic band emission from the borate host. The CuO doping produced a new contribution to band emission characteristic of Cu + . Further, significant decrease of Sm 3+ visible luminescence was evidenced in accord with a quenching effect induced by Cu 2+ . The analysis of Sm 3+ emission decay curves harmonized with the occurrence of two populations of Sm 3+ ions (single, interacting). The two decay components showed significant 4 G 5/2 lifetime decrease with increasing CuO content demonstrating an efficient Sm 3+ → Cu 2+ energy transfer.

Reactive air brazing of 3YSZ ceramic to aluminized Crofer22H stainless steel using Ag–CuO fillers

AbstractIn this work, an effective protected Al2O3layer was fabricated first on the surface of Crofer22H by reactive air aluminization to suppress cathodic poisoning in solid oxide fuel cells. Then, the reactive air brazing of aluminized Crofer22H to 3YSZ ceramics was carried out by using Ag–CuO fillers. The effects of CuO content and brazing temperature on the interfacial microstructure and mechanical properties of the joints were studied in detail. The results indicated that maintaining a continuous Al2O3layer was the prerequisite for achieving a reliable joint. And the interfacial reaction gradually became intense with the increase of CuO content, and the continuity of the Al2O3layer was disrupted as it was increased to 6 mol%. The well‐connected joints could be achieved when brazing at 970–1100°C with Ag–2CuO filler. The interfacial microstructure did not obviously change with increasing temperature, and the joint strength was stable at ∼35 MPa. While the interfacial reaction gradually weakened with increasing temperature as brazing with Ag–4CuO filler, the well‐connected joints were obtained when brazing above 1000°C, and the maximum shear strength of ∼44.3 MPa was obtained when brazing at 1050°C for 30 min.

The incorporation of Cu into the clinker phases.

The effect of CuO addition on the phase composition of clinker and the Cu incorporation into the structure of clinker phases was monitored under laboratory conditions. Separate synthesized CuO-doped clinker phases as well as clinkers with different CuO content up to 4 wt.% were characterized by XRD, optical and electron microscopy with EDS analysis. It has been found that Cu tends to form a separate phase or a double oxide with Ca and incorporates in the clinker phases to a limited extent, except for C4 AF. With increasing CuO content in clinker, its phase composition changes, and the size of alite crystals increases.

Crystallization, spectroscopic and dielectric properties of CuO-added magnesium aluminosilicate-based glasses

In this work, CuO-doped MgO-Al2O3-SiO2 based glasses have been synthesized successfully through conventional melt quenching method, and the effect of CuO content on the structure and properties of the glasses was investigated. The results revealed that CuO could act as a glass modifier to depolymerize the silicate network and its effect was superior to that of MgO. In addition, the main crystalline phase was α-cordierite (Mg2Al4Si5O18), indicating that copper ions did not participate in the formation of the crystalline phase, and still existed in the interstitial position. The characteristic absorption band around 750 nm owing to the 2B1g→2B2g transition of Cu2+ ions appeared on the optical transmittance spectra, which confirmed the existence of Cu2+ ions in the tetragonally distorted octahedral sites. The luminescence center was caused by Cu+ ions, and the luminescence lifetime decreased with the addition of CuO. The dielectric constant and dielectric loss increased with the increase of CuO content, indicating an increase in the insulation performance. Finally, the obtained chromaticity coordinate parameters indicate that the prepared CuO-doped magnesium aluminosilicate-based glasses can be applied in optical and electrical fields.

Effect of mixed ZnO/CuO nanoparticles on the structural, morphological, and topographical properties

In the present work, pure and composite ZnO/CuO were effectively deposited by chemical spray pyrolysis. Structural, morphological, and topographical features have been well investigated and explained. XRD analysis showed a polycrystalline structure with hexagonal and monoclinic systems for ZnO and CuO, respectively. The crystal size that calculated from XRD patterns has decreased with the increase of CuO content, while the dislocation density and the micro strain have increased. These results lead to high defects in the structure of the nanocomposite which will be more efficient in a specific application. Moreover, the morphology of the samples was examined by FESEM and it was spherical-like shapes and has elevated points, whereas the EDX confirm the existence of the employed materials without any other undesired materials. The topography of the surface depicted a slightly rough surface which will be suitable for different nanoelectronics devices.

Fabrication of ZnO/CuO Hybrid Nanocomposite for Photocatalytic Degradation of Brilliant Cresyl Blue (BCB) Dye in Aqueous Solutions

Here in the present study, we report the synthesis of ZnO nanoparticles, ZnO/CuO(3%), ZnO/CuO(5%), and ZnO/CuO(10%), nanocomposites using simple precipitation method with variation of CuO content and the activities of prepared samples were investigated for degradation of Brilliant Cresyl Blue (BCB) dye under visible light conditions in aqueous solutions. The structural, morphology, optical and compositional characteristics of fabricated samples were characterized by using Fourier Transform Infra-Red (FTIR) Spectroscopy, Field Emission Scanning Electron Microscopy combine electron dispersive spectroscopy (FESEM-EDS) and UV-vis spectroscopy. FESEM images show that ZnO nanoparticles are polygon like shape structure while ZnO/CuO have polygon and sheet shape structures. XRD patterns reflect the high crystalinity and purity of samples. The optical band gap values determined from optical absorption method indicate that band gap energy decreased with increase of CuO content in ZnO. The catalytic efficiency of the ZnO/CuO hybrid nanocomposite was observed to be higher than the ZnO nanoparticles under similar reaction conditions, 97.30% of Brilliant Cresyl Blue (BCB) dye was degraded after 100 min of irradiation of visible light radiation using the ZnO/CuO(5%) hybrid nanocomposite. The higher efficiency of ZnO/CuO compare to ZnO may be due to increased surface area and decreased band gap energy. The kinetic study of the photoctalytic degradation displayed that hybrid ZnO/CuO degrdaded dye with high rate constant k (34.88x10-3 min -1) compare to ZnO (k, 7.00x10-3 min-1). The optimization of reaction conditions of photodegradation process were attained by the variation in reaction factors such as pH, dye concentration, catalyst amount, and reaction time.