Optical and electronic properties of MgPc-Ch-diisoQ blend organic thin film as an active layer for photovoltaic cells

Organic photovoltaic cells are a promising technology for generating renewable energy from sunlight. These cells are made from organic materials, such as polymers or small molecules, and can be lightweight, flexible, and low-cost. Here, we have created a novel mixture of magnesium phthalocyanine (MgPc) and chlorophenyl ethyl diisoquinoline (Ch-diisoQ). A coating unit has been utilized in preparing MgPc, Ch-diisoQ, and MgPc-Ch-diisoQ films onto to FTO substrate. The MgPc-Ch-diisoQ film has a spherical and homogeneous surface morphology with a grain size of 15.9 nm. The optical absorption of the MgPc-Ch-diisoQ film was measured, and three distinct bands were observed at 800-600 nm, 600-400 nm, and 400-250 nm, with a band gap energy of 1.58 eV. The current density-voltage and capacitance-voltage measurements were performed to analyze the photoelectric properties of the three tested cells. The forward current density obtained from our investigated blend cell is more significant than that for each material by about 22%. The photovoltaic parameters (Voc, Isc, and FF) of the MgPc-Ch-diisoQ cell were found to be 0.45 V, 2.12 μA, and 0.4, respectively. We believe that our investigated MgPc-Ch-diisoQ film will be a promising active layer in organic solar cells.

Synthesis of novel Cu/Fe based benzene Dicarboxylate (BDC) metal organic frameworks and investigations into their optical and electrochemical properties

In the recent past Metal-organic frameworks (MOFs) based thin films have demonstrated superior performance in various technological applications such as optical and optoelectronic devices, electrochemical energy storage, catalysis, and sensing. Herein we report tuning the optical performance of stable complexes using Cu and Fe metal ions with carboxylate benzene dicarboxylic (BDC), leading toward the formation of novel MOF structures. The formation of Cu-BDC and Fe-BDC were confirmed by XRD and SEM studies. The thermal stability of two MOFs was investigated, indicating that, the Cu-BDC is more stable than Fe-BDC. Further, the optical properties were investigated in the wavelength range 325-1100 nm, and the Fe-BDC exhibited greater optical transmission properties than Cu-BDC by 33 %, as investigated by Wemple-DiDomenico and Tauc models. The dispersion parameters related to optical studies for Cu-BDC were better in comparison to Fe-BDC, which could be attributed to the increase in Cu valence electrons due to an increase in the number of cations. The electrochemical behavior in terms of CV measurements shows the presence of pseudo capacitance in both Fe-BDC and Cu-BDC MOFs. The improved CV performance of Cu-BDC MOF suggests that it could be used as a storage material. This work successfully demonstrates the tailoring of optical properties related to MOF thin films through the formation of stable complexes using BDC as a potential material for the fabrication of OLED's and Solar cells. The improved CV performance suggests that these MOF based materials could be used as anodes in fabrication of batteries or supercapacitors.

CuO nanoparticles mixed with activated BC extracted from algae as promising material for supercapacitor electrodes

The present analysis aims to use existing resources to lower the cost of electrodes and reduce environmental pollution by utilizing waste materials like green algae. In the present research, the hydrothermal carbonization technique was utilized to synthesize a nano sized CuO mixed with activated biochar (CuO@BC) extracted from red sea algae (Chlorophyta). The CuO@BC sample was extensively examined using several advanced physical techniques, such as UV/Visible spectroscopy, FTIR, XED, HRTEM, SEM, EDX, BET, and TGA. The HRTEM indicated that the size of the particles is 32 nm with a larger surface area and without aggregations. The BET analysis of CuO@BC indicates that the material contains pores of a relatively large size and with a pore diameter of about 42.56 A°. The electrochemical analysis of CuO@BC modified glassy carbon electrode CuO@BC/GCE has been investigated using CV, GCD, and EIS techniques. This CuO@BC/GCE shows excellent electrochemical features that are significant for energy storage applications. The CuO@BC/GCE showed a specific capacitance of approximately 353 Fg-1 which is higher compared to individual materials. Overall, the research outcomes suggest that the CuO@BC/GCE shows potential for use in high-performance supercapacitors as energy storage systems that are eco-friendly and sustainable.

Morphology, structural properties, impedance spectroscopy, AC conductivity, and dielectric relaxation properties of boron subphthalocyanine chloride amorphous films

Through the use of thermal evaporation, boron subphthalocyanine chloride (B-subPcCl) films were created. X-ray diffraction pattern reveals that the B-subPcCl is characterized by amorphous nature, while atomic force microscopy images show that the surface topography of B-subPcCl is composed of homogeneous elliptical nanoparticles with grain size and roughness of 90 and 70 nm, respectively. The impedance measurements of B-subPcCl film at the temperature ranges of 298–398 K were studied and were fitted to the analog of a Rp//CPE equivalent electrical circuit model. The relationship between AC conductivity and frequency at different temperatures demonstrated that the correlated barrier hopping (CBH) model dominates the transport charge mechanism between the closest sites. The DC conductivity parameters were calculated, and they were compared with the relative organic compounds. The dependence of the dielectric constant (ε 1) and the dielectric loss (ε 1) on frequency showed a significant decrease of ε 1 and ε 2 values as the frequency increased. At different temperatures, the variation of the imaginary modulus (M 2) of B-subPcCl with frequency showed a relaxation process with an activation energy of 0.066 eV.

Synthesis, characterization and optical properties of nanosized lanthanum (III) complexes thin film with aryl-azo-pyrogallol derivatives

The present study is focused on the assembly of two new thin films based on the direct layer deposition of lanthanum ion from solution with two aryl-azo-pyrogallol ligands onto the surface of a glass substrate. Assembled lanthanum (III) complexes were characterized by different techniques including thermal gravimetric analysis, metal analysis by acid digestion and complexometric titration, Fourier transforms infrared, transmission electron microscopy, and X-ray diffraction. Two complexes were highly similar in their patterns and crystallinities with the characterized particle size range 23.16-23.31 nm. Energy gaps of the two complexes NS Na₃La(III)-(L1)₂ and NS Na₃La(III)-(L2)₂ were found to be 2.09 and 2.33 eV, respectively. Linear and calculated nonlinear optical properties have been studied for the two complexes. The nonlinear refractive index has been calculated and NS Na₃La(III)-(L2)₂ showed a high nonlinear behavior (n₂ = 8 × 10^-7 esu) and it could be a promising low-cost material in the optical nonlinear application.

Thin film assembly of nanosized cobalt(II) bis(5-phenyl-azo-8-hydroxyquinolate) using static step-by-step soft surface reaction technique: Structural characterization and optical properties

Nanosized (NS) cobalt (II) bis(5-phenyl-azo-8-hydroxyquinolate) (NS Co(II)-(5PA-8HQ)₂) thin films have been synthesized using static step-by-step soft surface reaction (SS-b-SSR) technique. Structural and optical characterizations of these thin films have been carried out using thermal gravimetric analysis (TGA), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HR-TEM) and X-ray diffraction (XRD). The HR-TEM results revealed that the assembled Co(II)-complex exhibited a uniformly NS structure particles in the form of nanorods with width and length up to 16.90nm and 506.38nm, respectively. The linear and nonlinear optical properties have been investigated. The identified energy gap of the designed thin film materials was found 4.01eV. The refractive index of deposited Co(II)-complex thin film was identified by thickness-dependence and found as 1.9 at wavelength 1100nm. In addition, the refractive index was varied by about 0.15 due to an increase in the thickness by 19nm.