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In this investigation, we achieved successful deposition of nanostructured cupric oxide (CuO) thin films onto glass substrates through implementation of successive ionic layer adsorption and reaction (SILAR), all carried out at room temperature. This approach has proven to be highly efficient and yielded favorable results in terms of film quality and uniformity. A comprehensive investigation was conducted to analyze the effect of gold (Au) on the structural, morphological, optical, and electrical properties of nanocrystalline CuO thin films. The structural analysis confirmed that the films were polycrystalline, exhibiting a monoclinic crystal structure with preferential orientations along the ( 1 ¯ 11 ) and (111) planes. The estimated crystallite sizes ranged from 20.37 to 30.77 nm, indicating the nanoscale nature of the films. Scanning electron microscopy/energy-dispersive x-ray analysis (SEM/EDX) was executed to reveal the Au dopant on the surface of CuO thin films. Surface analysis revealed the presence of uniformly dispersed CuO nanostructures across the film surfaces. Through optical investigations, it was observed that the bandgap energy of the CuO thin films decreased from 1.52 to 1.45 eV with increasing Au concentration. Furthermore, the average transmittance of the films exhibited a decrease from 4.9% to 1.3% as the Au concentration increased. The electrical properties of the Al/Au:CuO/n-Si heterojunction were studied using current–voltage (I–V) measurements for various light power densities. The Al/Au:CuO/n-Si heterojunction exhibited good photodiode behavior, with 3.44 A/W responsivity and 1.58 × 1010 Jones specific detectivity for the 2% Au-doped CuO interfacial layer. [ABSTRACT FROM AUTHOR]

CuO thin films were spray-deposited onto a glass substrate and the deposition temperature was varied from 450 to 550° C with 25° C steps. The 450° C deposition temperature was found to be the optimum condition for crystal growth. However, the FESEM images revealed that the grain size increases with raising the deposition temperature. To investigate the optical properties, the transmittance and reflectance data of the resulting films were recorded, and their optical constants, including absorption coefficient, band gap, Urbach energy, refractive index, extinction coefficient, and real and imaginary parts of the dielectric constant were calculated. All the prepared CuO thin films exhibited band gap values around 2.00 eV, which slightly declined with increasing the substrate temperature. The general trend of real and imaginary parts of the dielectric constant was increment and decrement, respectively, with increasing the substrate temperature. The spraydeposited CuO thin films were also excited at 486 nm, and the resulting photoluminescence (PL) spectra were recorded at room temperature. Three main and three shoulder peak emissions were detected in the recorded PL of all CuO thin films. The lowest peak intensity was related to the CuO thin film deposited at 500° C. [ABSTRACT FROM AUTHOR]

An FTO thin film was first deposited onto a glass substrate via the spray pyrolysis technique. To investigate the influence of the used salt and, consequently, structural properties on electrochemical performance, two precursor solutions were prepared from copper chloride dihydrate and copper acetate monohydrate and spray-deposited onto the FTO thin films. Considerable differences were observed in the physical characteristics of the resulting CuO thin films derived from different precursor solutions. The XRD results were employed to estimate the crystallite size and strain for the prepared CuO thin films via the Williamson–Hall method, as well as lattice parameters. Accordingly, the CuO thin film deposited from chlorine salt showed a greater crystallite size, lower strain, and unit volume cell. The Hall effect measurement revealed that there is slightly less resistivity for the CuO prepared from chlorine salt; however, mobility and carrier concentration were significantly different for the CuO thin films. The Randles–Sevcik equation was used to calculate the diffusion coefficient, and it is found that the structural characteristics of CuO grown from acetate salt (6.43 × 10–6 cm2/s) are in favor of better ion diffusion in compare with chloride salt (4.72 × 10–6 cm2/s). Similarly, the estimated equivalent distribution resistance from the Nyquist plot for CuO thin films spray-deposited from chlorine (250.11 Ω) and acetate (130.01 Ω) confirmed the better ion diffusion for the acetate solution-derived CuO thin film. Capacitance was calculated from cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy, all of which confirmed better ion storage performance in CuO deposited from acetate salt due to the superior ion diffusion characteristics of the mentioned thin film. [ABSTRACT FROM AUTHOR]

CuO thin film has a promising opto-electrical properties which make it used as absorber layer in thin film solar cell. So, in this work, CuO thin film has been synthesized and prepared by precipitation method and spin coating technique. It was observed it has narrow band gap (1.38 eV), high absorption coefficient (5.5 × 104 cm–1), optimum optical conductivity and high refractive index accompanied by low transmittance. XRD pattern is showed CuO nanocrystal has high crystallinity and low disorder which resulted in good optical absorption in the visible region. From SEM, it was observed the morphology of the CuO nanoparticles was rod-like particles which led to improve the opto-electrical properties. I–V curve is showed the current of CuO thin film is (0.6mA) which revels its photo-responsivity under light due to its high absorption coefficient. From the above results, CuO is a good absorber in thin film solar cell. [ABSTRACT FROM AUTHOR]

In this study, the effect of annealing temperature on the extended gate field effect transistor (EGFET) for pH sensors of CuO thin film was investigated. The CuO thin films were deposited on an indium tin oxide (ITO) substrate using the sol-gel spin-coating method. The thin films were then annealed in air ambient at 200 to 500 °C for 30 minutes. The sensitivity and linearity of the sensing electrodes were determined in a pH range from pH 2, 4, 7, 10 and 12. The sensing electrode annealed at 400 °C showed the highest pH sensitivity of 47.3 mV/pH. It showed that the post-annealing process improved the sensing performance of the device. The morphology characteristic was characterized by field emission scanning electron microscopy (FESEM) and showed a porous structure as the annealing temperature increased, indicating that the porous film could be the sensing electrode of an EGFET pH sensor. The hysteresis of the sensing electrode was measured in buffer solutions prepared at pH 7, pH 4, pH 7, pH 10, and pH 7 to find its pH response delay. These findings indicated that sol-gel spin-coated CuO thin film can be considered a promising candidate for applications as an EGFET-pH sensor. [ABSTRACT FROM AUTHOR]

CuO thin films with broccoli-like structure were prepared using a facile hydrothermal method to construct photocathodes for water-splitting application. The morphological, structural, and optical properties of thin films were characterized and measured using several techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), and ultraviolet-visible spectroscopy (UV-Vis). The thickness, structure, and morphology of CuO thin films can be controlled by varying the precursor concentration (Cp) and reaction temperature (Tr), which are also discussed. Moreover, the electrical properties of CuO thin films were also measured in the three-electrode system. The photocurrent density of photocathodes, when synthesized by a 0.5 M solution at 150 °C for 12 h, was 0.5 mA/cm2 at −0.6 V vs. Ag/AgCl, which is 1.8 times higher than that of photocathodes synthesized in a 0.1 M solution at 100 °C with the same reaction time. In addition, increasing the reaction temperature and precursor concentration aided in the enhancement of the IPCE and APCE values, which peaked at a wavelength range of 330–400 nm. [ABSTRACT FROM AUTHOR]

CuO thin films were successfully deposited using a simple, cost-effective and nearly room-temperature successive ionic layer adsorption and reaction routes. The material has been characterized using x-ray diffraction, field-emission scanning electron microscopy and transmission electron microscopy. Increase of grain size and decrease of microstrain were observed for a particular level of dipping (30 cycles) and further increase in dipping cycles shows a reverse tendency. The effect of the dipping cycle of the synthesized films on their supercapacitive, photocatalytic and ethanol-sensing performance were investigated. A 30-cycle dipped CuO thin film-based electrode provides a maximum specific capacitance of 585 Fg−1 at the voltage scan rate of 2 mVs−1 from cyclic voltammetry measurement and 554 Fg−1 at a current density of 1 Ag−1 from the charging to discharging curve. This electrode exhibited long-term cycle stability with 92.3% capacitance retention after 4000 cycles. CuO films synthesized for 30 dipping cycles showed the highest photocatalytic activities with 91.1% degradation of methylene blue under exposure to visible light of 200-W energy in a time duration of 4 h. Maximum sensitivity of 67% in the presence of 1500 ppm ethanol at the operating temperature 160°C was obtained for 30 dipping cycles film. Such attractive properties of low cost and facile synthesized CuO thin films makes them a suitable candidate for different commercial applications. [ABSTRACT FROM AUTHOR]

The influence of the presence of HCl and methanol in the precursor on CuO absorber layers deposited by spray pyrolysis has been investigated. The films were deposited on glass substrate at fixed substrate temperature of 450°C using 0.05 molar CuCl·2HO in deionized water containing a specific amount of HCl and methanol. The structural, morphological, electrical, and optical properties of the resulting thin films were studied to evaluate their suitability for solar applications. Presence of HCl increased the concentration of Cu ions in the precursor, leading to a rise in the Cu concentration in the resulting film, which improved the crystallinity with increased mean grain size, surface roughness, and carrier mobility at the cost of decreased carrier concentration. However, film deposited with excess HCl suffered from corrosion and huge cracks, making it unfavorable for solar applications. On the other hand, although presence of methanol improved the crystallinity of the resulting film, the surface was smooth due to lower deposition rate. Kubelka-Munk theory was used to estimate the optical bandgap of the deposited thin films, revealing values fairly close to optimum for solar cell applications. [ABSTRACT FROM AUTHOR]

In previous decades, investigation of superconductors was aimed either at finding materials with higher critical temperatures or at discovering nontypical superconducting behavior. Here, we present the cupric (CuO) thin films, which were synthesized by atomic layer deposition by using a metal-organic precursor, copper (II)-bis-(-dimethylamino-2-propoxide), and ozone as an oxidizer. The deposition process was optimized by employing a quartz crystal monitoring, and the contact between the deposited films and planar and three-dimensional SiO2/Si substrates was examined by scanning electron microscopy with a focused ion beam module. Phase and elemental composition were analyzed by X-ray diffraction and X-ray fluorescence. Two-probe electrical resistivity measurements revealed a resistivity drop below the critical temperature of 4 K, which may indicate low-temperature superconductivity of the CuO thin films. [ABSTRACT FROM AUTHOR]

Inefficient visible light photocatalytic degradation of organic pollutants, such as acetaminophen (ACE) and triclosan (TS), is one of the main limiting factors for implementing cost‐effective metal oxide photocatalyst for large‐scale deployment. Here, a highly efficient CuO thin film photocatalyst is developed through rapid thermal annealing. The CuO thin film is decorated with Pd nanostructures for enhanced visible light degradation of ACE and TS. It is shown that compared to the as‐deposited thin CuO film photocatalyst, the rapid thermal assisted CuO photocatalyst can significantly enhance charge generation and separation efficiency through improvement of crystallinity and reduction of recombination centres. Furthermore, it is demonstrated that the incorporation of Pd nanostructures can considerably increase optical absorption, which further improve the photocatalytic performance through the enhancement of surface plasmon resonance. The CuO film with the 40 s of Pd sputtering (Pd40–CuO) shows the highest performance for photocatalytic degradation of both ACE and TS. The Pd40–CuO film shows good stability and does not show any considerable reduction in photocatalytic activity after five cycles. This indicates the high potential of Pd40–CuO for water and wastewater treatment on industrial scale. Application of Pd‐decorated CuO thin film for photocatalytic degradation of acetaminophen and triclosan in aqueous solution is presented. The effect of thermal treatment on the photocatalytic activity of the CuO thin film is investigated. The photocatalytic degradation mechanism is comprehensively discussed in this article. The stability and recycling of photocatalysts are investigated. [ABSTRACT FROM AUTHOR]