Electrochemical Determination of Famotidine in Real Samples Using rGO/Cu2O Nanocomposite Modified Carbon Paste Electrode

Here, we developed a sensitive electrochemical sensor for famotidine (FAT) using Cu2O nanoparticles and reduced graphene oxide (rGO) as a sensing platform. The Cu2O nanoparticles and rGO were synthesized through a simple process and characterized by versatile analytical methods. The prepared Cu2O nanoparticles and rGO were taken to modify the carbon paste electrode (Cu2O/rGO/CPE) and developed for the electrochemical analysis of the FAT at pH 6.0. Cu2O/rGO/CPE showed superior electrocatalytic activity for detecting FAT, attributed to the high surface area of rGO and the electrocatalytic properties of Cu2O nanoparticles. The designed FAT sensor exhibited two linear ranges from 0.1-3 µM and 3-50 µM with a detection limit of 0.08 µM (S/N=3) using a differential pulse voltammetry. The proposed sensor also showed a repeatable and stable response over one month with negligible interference from usual organic and inorganic species. The sensor was also validated measuring FAT in real samples (urine, serum and pharmaceutical tablet) with good recovery values from 99.6 to 110.9%.

Synthesis of Blend Polymer (PVA / PANI)/Copper (1) Oxide Nanocomposite: Thermal Analysis and UV-Vis Spectra Specifications

Copper (1) oxide nanoparticles together with matrix polymers of polyvinyl alcohol (PVA) and polyaniline (PANI) composite films were synthesized, as these materials are of importance in optoelectronic applications. ‎Nanoparticles of Cu2O were produced by chemical precipitation. Polymerization of aniline was carried out through polymerization in an acidic medium. Structural, thermal, and optical properties of PVA+PANI/Cu2O nanocomposite were inspected by x-ray diffraction (XRD), scanning electron microscopy (SEM), fourier-transform infrared (FTIR), differential scanning calorimeter (DSC) and ultraviolet-visible spectroscopy (UV-Vis spectroscopy). X-ray diffraction peaks at 29.53°, 36.34°, and 42.22° indicated the presence of cuprous oxide nanoparticles, having high dispersions and limited size distributions. The estimated average size of Cu2O nanoparticles was ~ 17.1525 nm. A characteristic peak at around 2θ = 18.5° was attributed to periodical parallel and perpendicular polymer chains, which denoted the formation of PANI. SEM results indicated the symmetrical dispersion of Cu2O nanoparticles inside the hybrid polymer of PVA and PANI matrix, being potentially useful for encapsulation and acting as a good capping agent. FTIR results established the formation of PANI and Cu2O with nanocrystalline nature. DSC results revealed the appearance of one single peak of Tg which decreased with Cu2O content of 4% wt, followed by an increase of that value by increasing Cu2O content up to 16%wt. Thermogram analysis of the PANI and PVA embedded with Cu2O form showed an exothermic peak at (240-292)℃ affiliated to the cross-linking reaction, while the Tm value of prepared nanocomposites is just about close to that of PVA polymer. The results indicated that there is an increase in thermal stability due to the presence of Cu2O NPS within the matrix of polymers. The distinguishing peaks at 330, 347, and 457 nm which refer to PANI are assigned to π−π* electron transitions among the benzenoid rings. The high absorption intensity of the peak at 470 nm for the blended PVA+PANI having 12% wt of Cu2O NPS is assigned due to the inter-band transitions for electrons of the core copper as well as copper oxide. This points out that the increasing quantity of Cu2O NPs leads to increases in the amounts of highly oxidized structures in PANI and decreases in the doping electrons and length of conjugation throughout the incorporation of Cu2O NPs into PANI matrix. Depending on the practical results, it can be said that these polymeric nanocomposites can be efficiently used in photovoltaic technology applications.

Discharged Na5V12O32 Nanowire Arrays Coated with Cu-Cu2O for High Performance Lithium-Ion Batteries

Sodium vanadate have been widely used as a lithium-ion battery anode. However, its further application is restricted by the capacity attenuation during cycles because of its easy solubility in electrolyte, huge structural change, and low conductivity. Here, a lithium-ion battery electrode based on Cu-Cu2O coated Na5V12O32 nanowire arrays using a predischarge-electrodeposition method is freported. Remarkably, in the Cu-Cu2O@Na5V12O32 electrode, the Na5V12O32 nanowires function as the skeleton, and Cu-Cu2O nanoparticles function as the coating layer. At a specific current of 50 mA g-1, the composite electrode exhibits discharge and charge capacity of 837 and 821 mAh g-1 after 80 cycles, respectively, which is much higher than that of the Na5V12O32 nanowires electrode. This research provides a new pathway to explore electrode materials with enhanced electrochemical performance.

Biodegradation of cellulose fibers functionalized with CuO/Cu2O nanoparticles in combination with polycarboxylic acids

Sustainable biodegradation of cellulose fibers is critical for composting after the end of a product’s life. In this study, we aimed at investigating the effect of in situ synthesized CuO/Cu2O nanoparticles (NPs) with biocidal concentration on the biodegradation behavior of cotton fibers pretreated with 1,2,3,4-butanetetracarboxylic acid (BTCA) and succinic acid (SUC). Biodegradation of the fibers was evaluated by soil burial tests in garden soil and in model compost after different soil burial times. The results showed that the application of BTCA, SUC, and CuO/Cu2O NPs did not affect the hydrophilicity of the samples and allowed a smooth biodegradation process. The morphological and chemical changes during biodegradation, evaluated by FESEM and FTIR analyses, showed that the presence of CuO/Cu2O NPs slightly hindered biodegradation of the fibers after 18 days in soil. However, biodegradation was much faster in the model compost, where all samples, regardless of their chemical modification, almost completely degraded after only 11 days. Intense microbial growth on the surface of all samples after nine days of burial in garden soil and model compost was confirmed by the presence of proteins produced by the microorganisms. The total number of microorganisms in the garden soil remained almost unchanged and increased in the model compost after the burial test. The only exception was the sample with the highest concentration of CuO/Cu2O NPs, which caused a reduction in microbial growth but not complete growth inhibition. These results clearly showed that during material degradation, the cellulosic material supporting microbial growth prevailed over the suppression of microbial growth by CuO/Cu2O NPs.

Experimental And Theoretical Studies of Green Synthesized Cu2O Nanoparticles Using Datura Metel L

In biomedical applications, Cu2O nanoparticles are of great interest. The bioengineered route is eco-friendly for the synthesis of nanoparticles. Therefore, in the present study, there is an attempt to synthesis of Cu2O nanoparticles using Datura metel L. The synthesized nanoparticles were characterized by UV-Vis, XRD, and FT-IR. UV-Vis results suggest the presence of hyoscyamine, atropine in Datura metel L, and also, nanoparticles formation has been confirmed by the presence of absorption peak at 790 nm. The average crystallite size (19.56 nm) obtained by XRD. Further, the various functional groups have been confirmed through FT-IR. To highlight the peak of the dominant frequencies, Fourier Power Spectrum was also used to analyze the synthesized nanomaterials spectrum results. Density functional theory (DFT) further also used over a period of time to measure the energy of the substance, which seems to suggest a stable compound. Furthermore, the calculated energies, thermodynamic characteristics (such as enthalpies, entropies, Gibbs-free energies), modeled structures of complexes, crystals, and clusters, and predicted yields, rates, and regio- and stereospecificity of reactions were in good agreement with the experimental ones. Overall, the findings indicate the successful synthesis of Cu2O nanoparticles using Datura metel L. correlates with theoretical study.

Diclofenac degradation based on shape-controlled cuprous oxide nanoparticles prepared by using ionic liquid

Persulfate oxidation technology is widely used in wastewater treatment, but there are still many disadvantages, such as high energy consumption, side reaction and narrow pH applicability. Copper oxides can activate persulfate steadily with higher efficiency. In this paper, a novel preparation method of shape-controlled cuprous oxide (Cu2O) nanoparticles featured with high catalytic performance was explored. It was found that adding ionic liquid 1-butyl-3-methylimidazolium bromide ([BMIM]Br) during preparation of Cu2O can improve the degradation rate of diclofenac (DCF). Cu2O nanoparticles possess good stability in consecutive cycling tests, which was confirmed by X-ray photoelectron spectroscopy. The possible mechanism of Cu2O activating persulfate at different initial pH conditions was discussed based on electron paramagnetic resonance spin-trapping experiment. It was found that DCF was efficiently degraded in the Cu2O/peroxydisulfate (PDS) system within a broad pH range from 5 to 11. It proved via a quenching experiment that the activation process of PDS mainly occurs on the surface layer of Cu2O nanoparticles. As a result, shape-controlled Cu2O nanoparticles prepared by ionic liquid are expected to be used for in situ chemical oxidation, which is an effective oxidation processes to degrade DCF remaining in surface water and ground water.