Presence Of CuO Research Articles

As-deposited and dewetted Cu layers on plasma treated glass: Adhesion study and its effect on biological response

Improving the adhesion of nanosized copper films to a glass substrate is vital for their application in electronics and medicine, as it enhances their overall reliability. For this purpose, we employed Ar plasma etching (240 s) and magnetron sputtering to create copper layers on a glass substrate. Furthermore, we investigated the effect of subsequent solid state dewetting (at 300 °C) of Cu nanolayers on the interface stability. Increasing the sputtering time resulted in elevated copper concentration, UV-Vis absorption, conductivity, and surface roughness. The as-deposited and dewetted samples exhibited very good wettability with water contact angles below 60°. Importantly, plasma treatment improved the adhesion of the Cu layers to the glass. Subsequent dewetting accelerated surface diffusion and the oxidation of Cu atoms, causing structural and morphological changes. The presence of CuO after dewetting caused loss of the surface plasmon resonance (SPR) band in the UV-Vis spectrum and a decrease in sample conductivity due to the transformation of the copper layer from a metal to an oxide. Biological testing revealed a more pronounced bactericidal effect for the as-deposited Cu layer against E. coli and S. epidermidis on contrary to dewetted samples. The similar cytotoxic trend was observed for human dermal fibroblasts and hepatocytes. Nonetheless, biological testing confirmed better cell adhesion on dewetted Cu layers compared to the as-deposited ones. Therefore, our copper nanostructured samples could find application as antibacterial coatings of biomedical devices.

High‐efficient electrocatalytic CO2 reduction to HCOOH coupling with 5‐hydroxymethylfurfural oxidation using flow cell

AbstractAmong various products from electrocatalytic CO2 reduction (CO2ER), HCOOH is highly profitable one. However, the slow kinetics of anodic oxygen evolution reaction lowers overall energy efficiency, which can be replaced by an electro‐oxidation reaction with low thermodynamic potential and fast kinetics. Herein, we report an electrolysis system coupling CO2ER with 5‐hydroxymethylfurfural oxidation reaction (HMFOR). A BiOCl–CuO catalyst was designed to sustain CO2ER to HCOOH at partial current density of 500 mA/cm2 with FEHCOOH above 90% and 700 mA/cm2 with FEHCOOH above 80%. In situ and ex situ x‐ray absorption fine structure was used to capture the structure transform of BiOCl–CuO into metallic Bi and Cu during CO2ER process, and the presence of CuO will promote this transformation which are supported by DFT calculations. Coupling HMFOR with CO2ER, we realize both FEHCOOH and FEFDCA above 95% simultaneously, providing new prospects vista for the electrosynthesis of value‐added products from paired system.

Ice-Enabled Transfer of Graphene on Copper Substrates Enhanced by Electric Field and Cu2O.

Graphene films grown by the chemical vapor deposition (CVD) method suffer from contamination and damage during transfer. Herein, an innovative ice-enabled transfer method under an applied electric field and in the presence of Cu2O (or Cu2O-Electric-field Ice Transfer, abbreviated as CEIT) is developed. Ice serves as a pollution-free transfer medium while water molecules under the electric field fully wet the graphene surface for a bolstered adhesion force between the ice and graphene. Cu2O is used to reduce the adhesion force between graphene and copper. The combined methodology in CEIT ensures complete separation and clean transfer of graphene, resulting in successfully transferred graphene to various substrates, including polydimethylsiloxane (PDMS), Teflon, and C4F8 without pollution. The graphene obtained via CEIT is utilized to fabricate field-effect transistors with electrical performances comparable to that of intrinsic graphene characterized by small Dirac points and high carrier mobility. The carrier mobility of the transferred graphene reaches 9090 cm2V-1s-1, demonstrating a superior carrier mobility over that from other dry transfer methods. In a nutshell, the proposed clean and efficient transfer method holds great potential for future applications of graphene.

Ordering Bimetallic Cu-Pd Catalysts onto Orderly Mesoporous SrTiO3-Crystal Nanotubular Networks for Efficient Carbon Dioxide Photoreduction.

Artificial photosynthesis of fuels has garnered significant attention, with SrTiO3 emerging as a potential candidate for photocatalysis due to its exceptional physicochemical properties. However, selectively converting CO2 into fuels with desired reaction products remains a grand challenge. Herein, we design an updated method via an aging strategy based on the electrospinning technique to synthesize a single-crystalline Al-doped SrTiO3 nanotubular networks with self-assembled orderly mesopores, further modified by Cu-Pd alloy. It exhibits both high crystallinity and superior cross-linked mesoporous structures, effectively facilitating charge carrier transfer, photon utilization, and mass transfer, with a remarkable enhancement from 0.025 mmol h-1 m-2 to 1.090 mmol h-1 m-2 in the CO production rate. Meanwhile, the ordered arrangement of Cu and Pd atoms on the (111) surface can promote the rate-determining step (*CO2 to *COOH), which is also responsible for its good activity. The presence of CuO in the reaction confers a significant advantage for CO desorption, leading to a remarkable CO selectivity of 95.54 %. This work highlights new insights into developing advanced heterogeneous photocatalysts.

Ordering Bimetallic Cu‐Pd Catalysts onto Orderly Mesoporous SrTiO3‐Crystal Nanotubular Networks for Efficient Carbon Dioxide Photoreduction

AbstractArtificial photosynthesis of fuels has garnered significant attention, with SrTiO3 emerging as a potential candidate for photocatalysis due to its exceptional physicochemical properties. However, selectively converting CO2 into fuels with desired reaction products remains a grand challenge. Herein, we design an updated method via an aging strategy based on the electrospinning technique to synthesize a single‐crystalline Al‐doped SrTiO3 nanotubular networks with self‐assembled orderly mesopores, further modified by Cu−Pd alloy. It exhibits both high crystallinity and superior cross‐linked mesoporous structures, effectively facilitating charge carrier transfer, photon utilization, and mass transfer, with a remarkable enhancement from 0.025 mmol h−1 m−2 to 1.090 mmol h−1 m−2 in the CO production rate. Meanwhile, the ordered arrangement of Cu and Pd atoms on the (111) surface can promote the rate‐determining step (*CO2 to *COOH), which is also responsible for its good activity. The presence of CuO in the reaction confers a significant advantage for CO desorption, leading to a remarkable CO selectivity of 95.54 %. This work highlights new insights into developing advanced heterogeneous photocatalysts.

The Effect of Composition on the Properties and Application of CuO-NiO Nanocomposites Synthesized Using a Saponin-Green/Microwave-Assisted Hydrothermal Method.

In this study, we explored the formation of CuO nanoparticles, NiO nanoflakes, and CuO-NiO nanocomposites using saponin extract and a microwave-assisted hydrothermal method. Five green synthetic samples were prepared using aqueous saponin extract and a microwave-assisted hydrothermal procedure at 200 °C for 30 min. The samples were pristine copper oxide (100C), 75% copper oxide-25% nickel oxide (75C25N), 50% copper oxide-50% nickel oxide (50C50N), 25% copper oxide-75% nickel oxide (25C75N), and pristine nickel oxide (100N). The samples were characterized using FT-IR, XRD, XPS, SEM, and TEM. The XRD results showed that copper oxide and nickel oxide formed monoclinic and cubic phases, respectively. The morphology of the samples was useful and consisted of copper oxide nanoparticles and nickel oxide nanoflakes. XPS confirmed the +2 oxidation state of both the copper and nickel ions. Moreover, the optical bandgaps of copper oxide and nickel oxide were determined to be in the range of 1.29-1.6 eV and 3.36-3.63 eV, respectively, and the magnetic property studies showed that the synthesized samples exhibited ferromagnetic and superparamagnetic properties. In addition, the catalytic activity was tested against para-nitrophenol, demonstrating that the catalyst efficiency gradually improved in the presence of CuO. The highest rate constants were obtained for the 100C and 75C25N samples, with catalytic efficiencies of 98.7% and 78.2%, respectively, after 45 min.

Investigating the Anticancer and Antioxidant Potentials of a Polymer-Grafted Sodium Alginate Composite Embedded with CuO and TiO2 Nanoparticles

In this study, we conducted the synthesis of a composite material by grafting an acrylonitrile-co-styrene (AN-co-St) polymer into sodium alginate and incorporating CuO (copper oxide) and TiO2 (titanium dioxide) nanoparticles. The primary objective was to investigate the potential anticancer and antioxidant activities of the composite material. First, CuO and TiO2 nanoparticles were synthesized and characterized for their size, morphology, and surface properties. Subsequently, these nanoparticles were integrated into the sodium alginate matrix, which had been grafted with the AN-co-St polymer, resulting in the formation of the composite material. To confirm successful nanoparticle incorporation and assess the structural integrity of the composite, various techniques such as X-ray diffraction analysis (XRD), scanning electron microscopy-energy dispersive X-ray analysis (SEM-EDX), Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA) were employed. The composite material’s anticancer and antioxidant activities were then evaluated. In vitro cell viability assays using the HepG-2 cell line were performed to assess potential cytotoxic effects, while antioxidant (DPPH) assays were conducted to determine the composite’s ability to scavenge free radicals and protect against oxidative stress. Preliminary results indicate that the composite material demonstrated promising anticancer and antioxidant activities. The presence of CuO and TiO2 nanoparticles within the composite contributed to these effects, as these nanoparticles are known to possess anticancer and antioxidant properties. Furthermore, the grafting of the AN-co-St polymer into sodium alginate enhanced the overall performance and stability of the composite material.

Solanesol alleviates metal oxide nanoparticles generated toxicity in human placental BeWo cells

Recent research has provided evidence that metal oxide nanoparticles (NPs) have the potential to traverse the placental barrier, potentially endangering the health of both pregnant individuals and the developing fetus. The function of oxidative stress is of utmost importance in the pathophysiology of poor pregnancy outcomes. The therapeutic potential of solanesol in mitigating pregnancy complications is attributed to its robust antioxidant activity. The objective of this work was to inspect the preventative effects of solanesol on the detrimental effects generated by CuO and NiO NPs in human placental cells (BeWo). It was noticed that the exposure of BeWo cells to solanesol at concentrations ranging from 1 to 100 µg/ml for a duration of 24 h did not result in any harmful effects. However, the presence of CuO and NiO NPs led to a dose-dependent decrease in cell viability when exposed to dosages of 5 to 200 µg/ml for 24 h. It is noteworthy that solanesol significantly reduced the cytotoxicity that CuO and NiO NPs generated in BeWo cells. The data on apoptosis also demonstrated that CuO and NiO NPs have effect on the expression of the apoptotic gene caspase-3 and the decline of mitochondrial membrane potential. However, this effect was effectively reversed when solanesol was administered in combination with NPs. The findings of the mechanistic investigation indicate that the CuO and NiO NPs induced oxidative stress was notably negated when solanesol was concurrently treated. This paper presents novel findings indicating that the toxicity generated by CuO and NiO NPs in human placental cells was significantly alleviated by solanesol. Further work is necessary to explore the pharmacological potential of solanesol against nanoparticle-generated pregnancy problems.

Synthesis and Characterization of Nanocube Cu2O Thin Film at Room Temperature for Methylene Blue Photodegradation Application

Methylene Blue is a synthetic dye with a complex structure thus making it hard to decompose naturally. Among the decomposition methods of synthetic dyes is photodegradation using a semiconductor material. In this study, Cu2O semiconductor nanoparticle has been synthesized on the surface of conductive substrate indium tin oxide using the electrodeposition method at room temperature. The X-ray diffractometer analysis provides information on the presence of Cu2O in the sample and the shape of the Cu2O crystal system which is a nanocube. Scanning electron microscopy with energy-dispersive X-ray spectroscopy provides distribution mapping information based on the morphology and atomic composition of the sample. Impedance measured a maximum resistance to charge transfer value of 2500 Ω. Photodegradation test towards methylene blue achieved a percent of degradation was 62.00% for 120 minutes under visible light irradiation with initial and final absorbance values of 1.56351 abs and 0.896875 abs respectively.

Simple synthesis of Cu/Cu2O/CuO composites with dual adsorption capacity for conductometric NO2 detection

Starting from improving the sensing performance of sensing materials to NO2, it is still a challenge to synthesize a material that can simultaneously enhance the adsorption capacity of NO2 and the surface adsorbed oxygen content. In this paper, nano-sized octahedral HKUST-1 precursor was prepared by one-step hydrothermal method. After subsequent sintering treatment at different temperatures, a series of CuO-based composites with oxygen vacancies and pores were obtained. Among them, Cu/Cu2O/CuO composite shows the best response for 1 ppm NO2 at 50 °C (S =14.4), and excellent selectivity, moisture resistance and reproducibility. The minimum detection limit is as low as 50 ppb. In addition, XPS, PL, NO2-TPD analyses and DFT calculations were used to study the reasons in detail for the excellent NO2 gas sensing performance of Cu/Cu2O/CuO. The presence of Cu in the composite improves the ability of material to adsorb NO2, while the presence of Cu2O and oxygen vacancies make the material have more surface adsorbed oxygen. The combined effect of the two makes the material have good NO2 gas sensing performance. The synthesis of this composite material provides new ideas for improving the detection ability of toxic and harmful gases.

Enhanced photodegradation of CuCo2O4 nanoflower for the dye degradation of Rhodamine B and Methyl Violet

The investigation examined into the effect of different hydrothermal reaction temperatures and durations on the formation of nanoflower-shaped CuCo2O4 nanostructures (CCO NPs). The structural, morphological, functional, optical, and magnetic properties of the synthesized CCO NPs were thoroughly examined. The optimal calcination temperature was determined using Thermogravimetric and Differential Thermal Analysis (TG/DTA), which identified 400 °C as the ideal temperature. Following X-ray Diffraction (XRD) analysis, pure CuCo2O4 samples were formed, with calculated average crystallite sizes of 27 nm for CCO-A, 48 nm for CCO-B, 30 nm for CCO-C, and 31 nm for CCO-D samples. Fourier Transform Infrared (FTIR) analysis provided additional confirmation of pure CuCo2O4 formation, with characteristic bands in the 665–662 cm-1 and 583–567 cm-1 ranges indicating the presence of CuO and CoO bonds. SEM, High-Resolution SEM (HRSEM) and High-Resolution Transmission Electron Microscopy (HRTEM) all supported the observation of a distinct flower-like structural morphology. The optical properties of an optimized sample were revealed by UV–Visible Diffuse Reflectance Spectroscopy (UV-DRS) analysis, which revealed a band gap of 3.3 eV. According to Vibrating Sample Magnetometer (VSM) results, the magnetic behavior of CCO-D nanostructures at room temperature exhibited paramagnetic characteristics. The saturation magnetization (Ms), remanent magnetization (Mr) and coercivity (Hc) values were determined to be 0.26218 emu/g, 2.7214 × 10–3 emu/g and 29.787 Oe, respectively. To evaluate photocatalytic performance, the CCO-D photocatalyst was used to degrade Methyl Violet and Rhodamine B dyes. CCO-D degraded MV dye with greater efficiency (93%) than RhB (85%) when exposed to sunlight. These findings highlight CCO-D's potential as a photocatalyst for the degradation of organic dyes.

Photocatalytic reduction of CO2 over Ni-CuxO thin films towards formic acid production

Copper oxide (CuO) is an abundant and low-cost material, which is active as a photocatalyst under visible light due to its narrow band gap (1.3 eV). In the present work, CuO thin films at different Ni doping amounts (5, 10, and 30 % mol) were prepared using two different techniques: dip-coating and electrodeposition of Cu precursors over glass and PET substrates. X-Ray analysis results indicate the presence of Cu2O, CuO and Cuo phases in PET substrate films, while only CuO phase in Glass-substrate films. Glass substrate films presented a higher formic acid production performance reaching 50,000 μmol/g·h using 5% Ni doping on CuO. This higher activity was associated with a lower ratio between the adsorbed oxygen and the oxygen located in the crystal lattice, attributing this to the oxygen species adsorbed over the surface that could hinder the active sites of the material. Finally, PET substrate samples present a higher ratio between adsorbed oxygen and lattice oxygen, however, the Cu2O phase presents less affinity to adsorb CO2 molecules than CuO monoclinic phase reducing the photoactivity of the CO2 photoreduction. Majority charge carrier mobility of 4 cm2/Vs and 35 cm2/Vs for Cu2O and CuO respectively, with the charge carrier concentration of ∼1 × 1019 order was achieved switching the conducting type.

Preparation and comparison performance of CuO Nanopartecles and CuO/TiO2 / Nanocomposite and application in solar cell

Nanostructures of metal oxides of CuO, and TiO2 were prepared by the hydrothermal method. Also, CuO/TiO2 nanocomposites were prepared by the hydrothermal technique using an equal ratio of 1:1 The properties of the prepared compounds were investigated through Field Emission Scanning Electron Microscopy FE-SEM, Transmission Electron Microscopy TEM, X-Ray Diffraction. The images of FE-SEM have confirmed that the prepared TiO2 , CuO, and nanoparticles were structured as Nanoparticles, Spherical, and CuO/ TiO2 nanocomposites which were mixed in an equal ratio were structured as rocks-like structures. The results of the X-ray diffraction indicated the presence of CuO, and TiO2 as (monoclinic structures, Tetragonal) respectively. with the average crystallite sizes,( 13.10,8.65 and 10.12)nm, for CuO , TiO2 and CuO/TiO2 respectively. The optical properties of the prepared nanoparticles CuO , TiO2 , and CuO/TiO2 were studied through UV-Vis Spectroscopy. The optical band gap of the prepared products was determined by UV-Visible spectrophotometry and was found to be 2.1, 3.0, and 2.8 eV for TiO2, CuO, NPs, and CuO /TiO2 nanocomposites respectively. Dye-sensitized solar cells (DSSCs) fabricated based on TiO2, CuO, NPs, and CuO /TiO2 nanocomposites are casted onto (FTO) substrates (front electrode), while the back electrode is carbon/FTO-glass substrate. Two types of natural dyes were used in this study. Chlorophyll pigment in green leek and anthocyanin red pigment in cochineal pomegranate whereas iodine/ iodide KI/I2 is used as the electrolyte solution. The solar cells efficiency rates (1.51,0.74 and 0.94) for CuO, TiO2 NPs, and CuO /TiO2 nanocomposites/ are chlorophyll pigments present in green leek respectively. and The solar cells efficiency rates (1.20,0.558 and 0.88) for CuO, TiO2 Nps, and CuO/TiO2 nanocomposites/ anthocyanin pigment present in red pomegranate respectively

Environmental Remediation of Real Textile Dyeing Wastewater Under Visible Light and Inactivation of Pathogenic Bacteria Using ZnO/CuO Nano‐Needles

Textile industries have an immense existence in a country's economy. Large quantity of water is consumed by textile dyeing industries and produces volumes of wastewater. Treating these hazardous effluents to make them environmental friendly, using nanocatalysts is the best promising method. Metal oxide nanomaterials have emerged as an important tool for environmental remediation. Herein the hydrothermally synthesized ecofriendly and low‐cost zinc oxide/copper oxide nanocomposites (ZnO/CuO NCs) with different proportions of binary oxides are evaluated for the applications of degrading organic pollutants and antibacterial activity. The influence of doping is also studied in structural, optical, morphological, photocatalytic, and antibacterial activities. The presence of CuO in NCs affirms the formation of ZnO/CuO NCs. Photodegradation of Congo Red (CR) and real textile dyeing wastewater (TDW) under visible light irradiation by 0.5 M ZnO:0.5 M CuO NCs reveal them to act as a perfect catalyst by tuning doping concentration of Cu in ZnO, with 1.9 × 10−3 and 5.4 × 10−3 M min−1 rate constant. Hybrid nanocomposite materials exhibit high antibacterial activity against Staphylococcus aureus and Escherichia coli with 5 and 6 mm inhibition zone. The experimental characteristics of NCs are explained by a combination of electronic band structure due to size effect and tuning metal oxide proportions in comparison to that of pure metal oxide.

Application of physical vapor deposition technology for practical utilization of nano-size copper oxide for lead uptake from solution: kinetics, equilibrium, and recycling studies

For the first time, copper oxide-coated glass beads (CuO-GBs) were fabricated using physical vapor deposition (PVD) technology for sequestrating Pb2+ ions from solution is addressed. Compared to other coating procedures, PVD offered high-stability uniform CuO nano-layers attached with 3.0-mm glass beads. Heating of copper oxide-coated glass beads after deposition was rather necessary to achieve the best stability of the nano-adsorbent. Detection of nano-size copper oxide on the beads was made by FTIR (intense peak at 655cm-1 for CuO bond stretching) and XRF (Cu peak at 8.0keV). Scanning electron micrographs taken at high magnification power indicated the presence of CuO in nano-range deposited over glass beads. The maximum deposited amount of CuO on the beads was 1.1% and accomplished at the following operational conditions: internal pressure 10-5mmHg, Ar flow rate 8.0mL/min, voltage 84V, pre-sputtering time 20s, total sputtering time 10.0min, and post-heating temperature 150°C for 3h. A univariate analysis indicated that the optimum Pb2+ uptake by CuO-GBs from solution was achieved at pH 7.0-8.0, 7 beads/50mL, 120-min contact time, and 15-mg/L initial concentration. Kinetic data for Pb2+ uptake was best presented by a pseudo-second-order model with a relative prediction error of 3.2 and 5.1% for GBs and CuO-GBs, respectively. On the other hand, Pb2+ equilibrium isotherms at 25°C were fairly presented by the Langmuir model, and the predicted saturation values were 5.48 and 15.69mg/g for GBs and CuO-GBs, respectively. CuO and CuO-GBs had similar Pb2+ saturation values (~ 16mg/g), although the latter demonstrated 4 times faster kinetic, thanks to fixation CuO on glass beads. Moreover, the chemical stability of copper oxide-coated glass beads was tested under different conditions. Recycling of copper oxide-coated glass beads was also investigated, and 90% of the surface was recovered using 0.01-M HNO3.

Morphology-dependent activation of hydrogen peroxide with Cu2O for tetracycline hydrochloride degradation in bicarbonate aqueous solution

The design of efficient heterogeneous catalysts in bicarbonate-activated hydrogen peroxide systems (BAP) is a hot topic in wastewater treatment. In this work, Cu2O nanoparticles with different morphologies including cubic shape (c-Cu2O), octahedron shape (o-Cu2O) and spherical shape (s-Cu2O), were applied in BAP for the first time to degrade tetracycline hydrochloride (TC). Compared with Cu2+ ions and CuO, TC degradation was boosted in the presence of Cu2O in the BAP system, with the degradation rate following the order c-Cu2O > o-Cu2O > s-Cu2O. The morphology-dependent effects could be linearly correlated with the ratio of surface oxygen species (OS), but not with the surface area or Cu(I) ratio. The c-Cu2O catalyst with exposure of (100) facets contained 76.6% OS as the active site for H2O2 adsorption and activation, while the value was much lower for o-Cu2O and s-Cu2O with dominant (111) facets. The presence of HCO3− enhanced the interactions among Cu2O, H2O2 and TC, leading to facile oxidation of Cu(I) to Cu(II) by H2O2, and the formation of various reactive species such as hydroxyl radicals and Cu(III) contributed to TC degradation. This work provides a new method for enhancing H2O2 activation with heterogeneous catalysts by crystal facet engineering.

Fabrication, characterization and effects of CuO nanoparticles on the optical behavior of polypyrrole polymeric films

The successful preparation of flexible PPy/CuO nanocomposite consisting of polypyrrole (PPy) with copper oxide (CuO) was achieved. The structural analysis of PPy and PPy/CuO was conducted by EDX, SEM, TEM, and FTIR techniques, which providing the successful fabrications of PPy/CuO nanocomposite films. The EDX analysis of thePPy/CuO nanocomposite reveals the presence of characteristic peaks corresponding to the elements of C, Cu, N, and O, with weight percentages of 47.46%, 9.05%, 19.08%, and 24.41%, respectively. The obtained results provide confirmation that the PPy/CuO nanocomposite film does not exhibit the presence of any impurity components. The FTIR noticed that all peaks of PPy spectrum also showed in the spectra of PPy/CuO nanocomposite films with a little shifts in peaks, in which these shifts increase with increasing contents of CuO nanoparticles. The findings of this study indicate that there are interactions occurring between PPy/CuO. Furthermore, SEM was employed to elucidate the morphological of the (PPy) and PPy/CuO. The SEM demonstrate that the copper oxide (CuO) are evenly distributed within the nanocomposite films. Using Tauc's relation, the band gap and Urbach energy of PPy and PPy/CuO films. were determined. The addition of varying concentrations (2.5%, 5%, and 10%) of CuO to PPy increase the Urbach tail of PPy, resulting in energy values of 1.08 eV, 1.11 eV, and 1.13 eV, correspondingly. Simultaneously, the presence of CuO causes reduction in the band gap of PPy from 3.42 eV to 3.35 eV, 3.32 eV, and 3.30 eV. Consequently, the incorporation of CuO into PPy/CuO composite films induces both structural and optical modifications, rendering these films suitable for utilization in optoelectronic devices.

Cu-catalyzed convenient synthesis of 2-trifluoromethyl benzimidazoles via cyclization of o-phenylenediamines with hexafluoroacetylacetone.

An efficient and convenient method for the synthesis of 2-trifluoromethyl benzimidazoles is described in this paper. The cyclization reaction of various o-phenylenediamines with hexafluoroacetylacetone proceeded smoothly in the presence of Cu2O as the catalyst to produce 2-trifluoromethyl benzimidazoles in satisfactory to excellent yields (up to >99% yield). The CF3 source, hexafluoroacetylacetone, acted not only as cyclization partner, but also acted as a ligand for the Cu catalyst. Various synthetically useful functional groups, such as halogen atoms, cyano, and methoxycarbonyl groups, remained intact during the cyclization reactions. The reaction mechanism was thoroughly investigated and was determined to involve a seven-membered cyclic diimine intermediate.

Origin and mitigation of the beam-induced surface modifications of the LHC beam screens

All over Run 2, the LHC beam-induced heat load on the cryogenic system exhibited a wide scattering along the ring. Studies ascribed the heat source to electron cloud build-up, indicating an unexpected high Secondary Electron Yield (SEY) of the beam screen surface in some LHC regions. The inner copper surface of high and low heat load beam screens, extracted during the Long Shutdown 2, was analysed. On the low heat load ones, the surface was covered with the native Cu2O oxide, while on the high heat load ones CuO dominated at surface, and it exhibited a very low carbon coverage. Such chemical modifications increase the SEY and inhibit a proper conditioning of the affected surfaces. Following this characterisation, the mechanisms for CuO build-up in the LHC beam pipe were investigated on a newly commissioned cryogenic system allowing electron irradiation, surface chemical characterisation by X-ray Photoelectron Spectroscopy and SEY measurements on samples held below 15 K. In parallel, curative solutions against the presence of CuO in the LHC beam screens were explored, which could be implemented in-situ to recover a proper conditioning and lower the beam-induced heat load.

Boosting H2 storage capability of Er+3 manganite by adding CuO and g-C3N4 in the form of a four-component nanocomposite

Herein, the as-prepared ErMnO3/ErMn2O5/CuO/g-C3N4 nanocomposite is used for H2 storage. This product is synthesized during two steps: in-situ synthesis of ErMnO3/ErMn2O5/CuO (NC-1), and adding g-C3N4 to prepare ErMnO3/ErMn2O5/CuO/g-C3N4 nanocomposite (NC-2). ErMnO3 emerges in the form of ErMnO3/ErMn2O5 (EMO/EMMO) at calcination temperatures <1200 °C. Two-dimensional structure of EMO plays a substrate for deposition of EMMO, CuO and g-C3N4. The results show that presence of CuO has no effect on the optical property of EMO/EMMO while adding g-C3N4 affects it and of course the band gap increases by agglomeration of the particles deposited on the EMO. Changing the magnetic properties in every change-step is notable. EMO represents a ferromagnetism characteristic that is altered to paramagnetic when NC-1 is prepared, and NC-2 presents a ferromagnetism behavior. Furthermore, the results show that CuO and g-C3N4 are used as boosters to increase H2 storage capacity of EMO/EMMO.