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Metal-organic frameworks (MOFs) are emerging as pivotal porous crystalline materials with diverse applications. Typically, MOFs are synthesized using solvothermal techniques at high temperatures and pressures. In this study, a novel approach was employed to synthesize zinc-based MOFs, specifically MOF-5, at low temperatures (up to 50 °C) via chemical mixing at standard pressures. Varying the temperature and solvents, N-methyl-2-pyrrolidone (NMP) and N,N-dimethylformamide (DMF), in the chemical mixing process, the highest yield of the material was observed with DMF at 50 °C (M1). Two additional samples, M2 and M3, are synthesized at room temperature using DMF and NMP, respectively. Despite similarities in XRD, Raman, and FTIR analyses confirming successful MOF-5 formation, noticeable differences in sample morphology arise due to distinct synthesis conditions, particularly solvent and temperature variations. The MOF-5 samples exhibit UV absorption with varying band gaps. Notably, when employed as photocatalysts for organic dye (methylene blue) degradation, M2 outperforms others, achieving an impressive 85% degradation under simulated solar light irradiation. This work underscores the significance of tuning MOF photocatalyst properties through tailored synthesis routes, recognizing the profound impact of morphology and elemental composition on enhancing photocatalytic dye degradation performance. Copyright © 2024 by Authors, Published by BCREC Group. This is an open access article under the CC BY-SA License (https://creativecommons.org/licenses/by-sa/4.0).

This report investigates the effect of substrate and nitrogen (16 keV N+) ion implantation on the structural, morphological, compositional, and electrical properties of V2O5 thin films which are grown by thermal evaporation on various substrates, including glass, Si, and sapphire (termed V2O5:Gl, V2O5:Si, and V2O5:Sp, respectively). Structural analysis showed the formation of the mixed (α, and β-V2O5) phases on all substrates; however, the β-V2O5 phase is highly dominant in the V2O5:G and V2O5:Si samples. A deformation in the β-phase of V2O5 thin film under ion implantation-induced strain results in a change of crystallite size. Irradiation suppresses XRD peaks in relative intensities, indicating partial amorphization of the film with defect formation. Microstructural analysis confirmed the formation of uniform-sized nanorods for V2O5:Si, whereas isolated crystallites were formed for other types of substrates. Thermal conductivity may influence the size and shapes of V2O5 crystallite forms on different surfaces. Silicon absorbs heat more effectively than sapphire or glass, resulting in nanorod formation. A decrease in optical bandgap and electrical conduction has been observed due to increased oxygen vacancies, induced electron scattering, and trapping centres on N+ implantation. The present study thus offers the unique advantage of simultaneous reduction in optical band-gap and conductance of V2O5 thin films, which is important for optoelectronic applications.

The present work focuses on studying the optical properties of the pristine PEDOT:PSS and the PEDOT:PSS modified with de-ionized water, ethylene glycol and MWCNT. The effect of various additives on the absorption, the refractive index, and the dielectric constant has been inspected. The refractive index dispersion has been analyzed using the single oscillator model developed by Wemple and DiDomenico. The optical constants, such as the dispersion energy, the single oscillator energy, the average oscillator strength, the average interband oscillator strength, the long wavelength refractive index, and the plasma resonance frequency have been determined. The energy bandgap was found reduced with the addition of EG and MWCNT representing a red shift and a conformational change in the PEDOT:PSS from a benzoid to a quinoid structure. The UV-visible absorption spectrum indicates the creation of free charges. The increase in the refractive index with doping suggests the formation of localized energy states within the energy bandgap. These localized states act as recombination centers and increase the low energy electronic transitions. The dielectric constant was also found increased in the modified samples, exhibiting advantages for the formation of conducting thin films. A phase segregated morphology was obtained for the solvent treated PEDOT:PSS, and the MWCNTs were observed to be uniformly distributed throughout the polymer. Furthermore, the optical conductivity has been calculated to give comprehensive information about material properties and their systematic selection for desired applications. Keywords: PEDOT:PSS, Optical properties, Refractive index, Ethylene glycol, MWCNT, Optical conductivity

Abstract This work presents a theoretical procedure to calculate various parameters needed for the installation of a photovoltaic water pump (PVWP) system. Specifically, the monthly optimum tilt angle of PV arrays is calculated, which will allow larger quantities of water to be pumped each month. For this, a simple performance optimization procedure is developed using solar radiation data. The investigations are based on the solar radiation data of New Delhi, India. The total amount of water pumped is compared with that by keeping the solar panels fixed throughout the year. The total amount of water that can be extracted by using manually adjustable arrays is found to be greater by 3–5%. This may be an alternative to an automatic sun tracker, which is not only expensive but also requires more space and maintenance. This method allows for analyzing the performance of low‐cost water pumping systems that may be used for both domestic and irrigation purposes.