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Transparent conducting oxide thin films have attracted significant research attention owing to their potential applications in solar cells and other optoelectronic devices. Herein, the influence of solvent admixtures containing methanol (CH3OH) and water (H2O) in varying ratios on the optoelectronic characteristics of fluorine-doped tin oxide (FTO) thin films prepared by the spray pyrolysis method has been explored. Several analytical techniques were employed to understand the relationship of solvent composition with the structure, morphology, and topography of the grown FTO thin films. Scanning electron microscopy analysis showed a decrease in the thickness of the thin films from 8.2 μm for M0 (0 vol% CH3OH) to 456 nm for M90 (90 vol% CH3OH), which was attributed to the change in mist formation dynamics. The average transmittance (T) of FTO thin films in the visible range increased when the CH3OH content was increased in the spraying solution due to the decreased thickness and Urbach energy and increased band gap. On increasing the CH3OH content in the spraying solution, the sheet resistance (Rs) decreased due to increased carrier density and enhanced mobility. The best sample prepared (M90), with pyramidal surface morphology, showed promising T (400–800 nm) and Rs of 73% and 8 Ω □−1, respectively. M90, exposed to harsh thermochemical conditions, i.e. 550 °C (3 h), 1 M H2SO4 (72 h), and 1 M KOH (72 h), retained its optoelectronic characteristics well. The figure of merit, determined by taking into account both T and Rs, was also found to be the highest for M90. To demonstrate the utility of the prepared FTO thin films in different optoelectronic devices, Cs0.05(FA0.92MA0.08)Pb(I0.92Br0.08)3 perovskite solar cells were prepared on M90 in an inverted configuration, and a power conversion efficiency of 14% was realized under standard AM 1.5G illumination. The series of prepared solar cells on M90 is on par with the other high-efficiency solar cells, demonstrating its superior electrical characteristics and reliability to be used for various applications. [ABSTRACT FROM AUTHOR]

Porous materials are promising candidates for the removal of organic pollutants from different water bodies. Among porous materials, cryogels are more attractive candidates due to their macro-porosity and rapid adsorption. This work evaluated the fabrication and adsorption capability of macro-porous Gum Arabic-based Cryogel. The fabricated Gum Arabic cryogel was modified and protonated to the protonated modified Gum Arabic Cryogel to compare its adsorption capacities for three different dyes. The successful fabrication of cryogel was confirmed by Fourier Transform Infrared spectroscopy, Differential Scanning Calorimetry, Thermal gravimetric analysis and Scanning Electron Microscopy. The protonated modified Gum Arabic Cryogel showed enhanced adsorption capability towards subjected dyes by following second-order rate kinetics. These cryogels can be employed as an efficient adsorbent to remove toxic contaminants from wastewater effluents. [ABSTRACT FROM AUTHOR]

The synergistic combination of 1D TiO2 nanorods and BiVO4 results in compatible electronic band structure alignment at their interfaces to ensure enhanced photoactivated charge separation and transportation under visible light irradiation. Herein, the plasmonic effect of platinum on 1D BiVO4/TiO2 nanorods was explored to establish charge transfer at the heterojunctions and improve the activities of methanol oxidation. Structural, compositional, morphological and electrochemical performance was explored. Noticeably, 10-Pt/BiVO4/TiO2 showed an excellent current density of 64.6 mA cm−2 under 100 mW cm−2 illumination as compared to 12.5 mA cm−2 under dark conditions. Moreover, the highest lifetime of 227.3 ms under light was observed as compared to 63.6 ms under dark conditions. Moreover, electrochemical impedance spectroscopy (EIS) studies of 10-Pt/BiVO4/TiO2 showed the least charge transfer resistance (Rct) of 161 Ω under one sun light in comparison to 385 Ω under dark conditions. Moreover, the methanol oxidation reaction (MOR) efficiency for 5, 10 and 15 cycles of Pt over BiVO4/TiO2 was found to be 335%, 417% and 78%, respectively. The surface plasmon resonance (SPR) property of Pt was enhanced with the substrate of the 1D BiVO4/TiO2 heterojunction, and this strategy showed its unprecedented potential to be utilized for electrocatalytic and photo-electrocatalytic applications. [ABSTRACT FROM AUTHOR]

Wastewater treatment is indispensable as wastewater can lead to adverse health effects and deteriorate the quality of life on earth. Photocatalysis is a facile methodology to address this issue. In this study, nanocomposites (NCs) of manganese oxide (Mn3O4) and nickel oxide (NiO) were synthesized in different weight ratios via the solid-state reaction route. Structural properties, optical properties, surface morphology, and functional group analysis of the synthesized nanomaterials were conducted using X-ray diffraction (XRD), UV– Vis spectroscopy, scanning electron microscopy (SEM) along with energy-dispersive X-ray (EDX) analysis, and Fourier-transform infrared (FTIR) spectroscopy, respectively. The bandgap of the nanocomposite decreases significantly from 2.35 eV for the Mn3O4 NPs to 1.65 eV for the Mn3O4/NiO nanocomposite (NC). Moreover, adsorption studies followed by the photocatalytic performance of the Mn3O4/NiO NCs were evaluated to determine the removal of methylene blue (MB) dye from wastewater. The photocatalytic performance of the nanocomposite enhances as the ratio of Mn3O4 in the composite increases from one weight percentage to three weight percentage. The photocatalytic degradation efficiency was calculated to be 95%. The results show that the synthesized NCs could play an important role in photocatalytic wastewater purification and environmental remediation. [ABSTRACT FROM AUTHOR]

In this study, polysulfone (PSf) nanocomposite membranes (NCM) have been fabricated by reinforcement with silica-modified zeolite (SiO2-MZ) and polyimide (PI)-SiO2-MZ as inorganic nanocomposite (NC) fillers. To evaluate the improvement in structural, mechanical, and thermal properties of PSf matrix, these nanofillers were incorporated systematically from 1 wt% to 10 wt%. Morphological analysis using transmission electron microscopy and scanning electron microscopy shows better compatibility between PI-SiO2-MZ as the inorganic nanofiller and polymer matrix as compared to SiO2-MZ filler. Physical characteristics of NCMs were studied by Fourier transform infrared spectroscopy and X-ray diffraction analysis. The appropriate ratio of PI-SiO2-MZ as nanofiller in PSf matrix was found through structural analysis. Thermal analysis using differential scanning calorimetry revealed an increase in glass transition temperature (T g) with increasing filler concentration. Young's modulus of PSf/SiO2-MZ NCM (10 wt%) was found to be 1109 MPa, which was improved to 1438 MPa for PSf/PI-SiO2-MZ (10 wt%) NCM. Membrane properties like swelling degree and porosity were also calculated. The degree of swelling of NCMs decreases with decrease in the hydrophilicity of the solvent. Antibacterial properties of NCMs were explored against four bacterial strains namely Klebsella pneumonia, Salmonella typhi, Bacillus subtilis, and Staphylococcus aureus. Good antibacterial activities were obtained for PSf membranes reinforced with PSf/PI-SiO2-MZ NC filler. [ABSTRACT FROM AUTHOR]

In this work different compositions of smart poly(N-isopropylacrylamide-vinylacetic acid-acrylamide) poly(NIPAM-VAA-AAm) microgels with different vinyl acetic acid (VAA) contents have been synthesized successfully by conventional free radical emulsion polymerization. Silver metal nanoparticles (NPs) were fabricated inside the microgels network by insitu reduction method using sodium borohydride (NaBH4) as reducing agent. The confirmation of polymerization and entrapment of metal NPs were carried out by FT-IR spectroscopy. Dynamic laser light scattering (DLLS) technique was used for calculating average hydrodynamic diameter of microgel particles. The optical properties of silver NPs were studied by UV-Visible spectroscopy at various conditions of pH and temperature. The hybrid microgels show red shift and increase in intensity of surface plasmon resonance (SPR) band with the increase in temperature and decrease in pH of the medium. The synthesized materials were used as catalysts in the reduction process and it was found that the catalyst composed of high amount of VAA shows enhanced catalytic activity. The apparent rate constant (k1) for catalyst composed of 12% VAA was doubled (5.6×10-3sec-1) as compared to 4% VAA containing catalyst (2.8×10-3sec-1). [ABSTRACT FROM AUTHOR]