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This study explores green-synthesized delafossite CuAlO2 as a hole transport layer (HTL) in a CH3NH3SnI3-based perovskite solar cells (PSCs) with an FTO/CuAlO2/CH3NH3SnI3/WO3/Au structure. The performances of the cell have been theoretically investigated using SCAPS-1D. Interface defects significantly impact cell efficiency, as defect density increases from 1014 cm−3 to 1020 cm−3 efficiency reducing from 25.3% to 24.45% in the HTL/perovskite junction and from 25.2% to 17.8% in the perovskite/electron transport layer (ETL) interface. PCBM as buffer layer at perovskite/ETL interface compensates for power conversion efficiency (PCE) losses. Optimizing parameters reveals the delafossite CuAlO2-based, lead-free perovskite solar cell achieving peak efficiency at 26.74%, with VOC, JSC, and FF values of 0.99 V, 33.43 mA cm−2, and 81.05%, respectively. This research underscores delafossite CuAlO2 as a promising HTL for eco-friendly, stable CH3NH3SnI3-based perovskite solar cells, emphasizing its potential in enhancing device performance. [ABSTRACT FROM AUTHOR]

This study emphasizes the synthesis of nickel oxide (NiOx + C) nanoparticles with varied graphite (C) proportions (1%, 2.5%, 5%, 7.5%, and 10%) using Aloe-Vera natural extract as a green reducing agent. Prepared NiOx + C nanostructures exhibited consistent X-ray diffraction patterns with no additional C peak, signifying enhanced interlayer spacing. The crystalline size (Dp) decreased from 27 nm to 20 nm with an increase in the amount of carbon (C). The determined bandgap (Eg) was 2 eV higher than bulk material due to formation extra energy level at defect sites. The shoulder peak at 1620 cm−1 agrees with the disorder-induced band from C and second-order bands of C at about 2700 cm−1 for NiOx + C. FESEM images confirm the hexagonal morphology. Not much particle aggregation was observed except for 10% C content. The selected area electron diffraction (SAED) confirms the existence of NiOx crystalline orientations including planes (111), (200), (220), (311), and (222). [ABSTRACT FROM AUTHOR]

The sol–gel technique has been used to produce Ag–SiO2 nanocomposite thin films consisting of silver nanoparticles embedded in a SiO2 matrix. The size of the silver nanoparticles is of about (4±0.2) nm when the firing temperature is in the (500–700 °C) range, as determined from ultraviolet-visible spectroscopy analysis. The increase of the firing temperature beyond 300 °C, was found to lead to an outer diffusion of Ag toward the surface. As a consequence the surface atomic concentration of Ag is found to increase from 1.3% to 12% for the as-dried (at 120 °C) and for those further fired at 600 °C, respectively. On the other hand, it is shown that the electrical behavior of these Ag–SiO2 nanocomposite films can drastically change from highly insulating to conducting depending on the firing temperature used. In the intermediate firing temperature (300–400 °C) range, the films were found to exhibit a reversible switching behavior with a resistivity transition of about 7 orders of magnitude between the insulating (OFF) and the conducting (ON) state. Such an electrical switching could be explained by a change in the predominant conduction mechanism of the films. [ABSTRACT FROM AUTHOR]

Thin films of different metals M (M=Ti, Zr, Hf, Nb, Fe, and Ni) of thickness around 10 nm are deposited on Si(100) substrates and a ∼30 nm Co film is deposited on these metal films using the magnetron sputtering method. Cross-sectional transmission electron microscopy (XTEM) shows the presence of a ∼2 nm buried ultrathin amorphous interlayer at the interface between the Co layer and the M layers (M=Ti, Zr, Hf, and Nb). X-ray reflectivity is used to determine the electron density of this buried ultrathin amorphous interlayer. X-ray diffraction (XRD) is used to determine the crystalline quality of the deposited Co film on these various metal film substrates. The XRD peaks of Co(111) and Co(222) are observed when Ti, Zr, Hf, and Nb are used as substrates. Pole figure measurements confirm that the Co film is highly textured on such metallic substrates. On the other hand no characteristic XRD peaks of cobalt are observed when Ni and Fe are used as the substrate, howe! ver, XTEM shows the presence of the Co film on those substrates. Theoretically, the heat of mixing (-ΔH) has been calculated for Co-M systems. The local temperature rise is estimated using the average heat capacity and the calculated heat of mixing of the amorphous interface compound (Co[sub 3]M). The local temperature rise due to the amorphous phase formation and hence better mobility of the further deposited metal atoms is the cause of highly textured Co thin films on such metal substrates. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The development of corrosion resistant superhydrophobic thin films on aluminum surfaces has attracted great interest for industrial applications. In the present work, zirconium-based superhydrophobic thin films were fabricated on AA6061 aluminum alloy substrates by a simple electrodeposition process. The thin film coated Al substrate exhibited excellent superhydrophobicity with a higher water contact angle of 162 ± 3° compared to the hydrophilic as-received Al substrate with a contact angle of 83±2°. The surface morphology of the fabricated thin films on Al substrate shows uniform micro-nano porous structures. The polarization resistance of the as-received Al and the zirconium-based superhydrophobic thin films on the Al substrate are 23 kO.cm² and 788 kO.cm², respectively. These results show excellent anti-corrosion property of zirconium-based superhydrophobic thin films to provide high corrosion protection for Al substrates. [ABSTRACT FROM AUTHOR]