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The present work aims to fabricate n-i-p forward perovskite solar cell (PSC) withئ structure (FTO/ compact TiO2/ compact TiO2/ MAPbI3 Perovskite/ hole transport layer/ Au). P3HT, CuI and Spiro-OMeTAD were used as hole transport layers. A nano film of 25 nm gold layer was deposited once between the electron transport layer and the perovskite layer, then between the hole transport layer and the perovskite layer. The performance of the forward-perovskite solar cell was studied. Also, the role of each electron transport layer and the hole transport layer in the perovskite solar cell was presented. The structural, morphological and electrical properties were studied with X-ray diffractometer, field emission scanning electron microscope and current-voltage (J-V) characteristic curves, respectively. J-V curves revealed that the deposition of the Au layer between the electron transport layer (ETL) and Perovskite layer (PSK) reduced the power conversion efficiency (PCE) from 3% to 0.08% when one layer of C. TiO2 is deposited in the PSC and to 0.11% with two layers of C. TiO2. Power conversion efficiency, with CuI as the hole transport layer (HTL), showed an increase from 0.5% to 2.7% when Au layer was deposited between PSK and CuI layers. Also, Isc increased from 6.8 mA to 17.4 mA and Voc from 0.3 V to 0.5V. With depositing Au layer between P3HT and PSK layers, the results showed an increase in the efficiency from 1% to 2.6% and an increase in Isc from 10.7 mA to 30.5 mA, while Voc decreased from 0.75 V to 0.5V

The present study aimed to synthesize and prepared an electron transport layer based on titanium isopropoxide, TiO2 paste and SnCl4:5H2O. An experimental investigation was used to describe the effect of TiO2 and SnO2 on the performance of perovskite solar cells based on the MAPbl3 perovskite active layer. The optical, morphological and electrical properties were studied using UV-Vis. spectrometer, field emission scanning electron microscope (FE-SEM) and current-voltage (J-V) curves respectively. (FE-SEM) images for C.TiO2, m.TiO2 and mix SnO2 with m.TiO2 refers that the surface of C.TiO2 is smooth and homogeneous with some crystals and for m.TiO2 has a homogenous layer with a small grain structure enhanced the surface area of the under-layer and improved the net efficiency of the cells. (C. TiO2/ m. TiO2 200 mg/ml) given a better performance compared with other ETL layers. The optimized solar cell structure (FTO/compact TiO2/mesoporous TiO2 200 mg/ml / Perovskite/ Spiro-ometad/Au) which gives a maximum power conversion efficiency (PCE) of 4.4% and filling factor 0.55.

Modeling the electrical properties of dye-sensitized solar cells (DSSCs) can fill the gap between the experimental and ideal performance observations for a reliable device diagnosis, design and optimization. The complex physical and chemical reactions between nanocrystalline semiconductor, electrolyte ions and dye molecules make their simulation an open issue to the researchers. Compared to the research works presented in literature, here, we provide a simpler, but more meaningful fit of current −voltage curves by developing a simulation model. The present work provides a reliable framework to extract electrical transport properties of the device, namely, diffusion coefficient, transport time, diffusion length, series resistance and performance parameters from steady state current–voltage curves without using interpretable frequency dependent methods, as well as transient characteristics. The model versatility makes it also capable of predicting the dye regeneration efficiency under short circuit, mid-voltages and high voltage ranges. The simulation method can be also implemented to compare the effect of different electrolytes as well as their species concentrations on regeneration efficiency and overall DSSCs performance. The whole model is designed in a flexible framework to be adapted to various kind of solar cells such as quantum dot and perovskite solar cells.

In this paper, Young’s modulus of polymers is experimentally measured using pressure sensors based on surface plasmon polariton. Theoretical relationships of changes in polymer reflective index due to applying pressure are investigated as well as the dependence of surface plasmon to the polymer reflective index. For the purpose of investigating the effects of the layers thicknesses, numerical simulation is performed using transfer matrix. Changes in resonance angle of surface plasmon due to applying pressure are experimentally studied as well. Practically, a sample of silicon rubber, as one of the most widely-used polymers, is checked and its Young’s modulus is measured as 8.1 MPa.

A solution processable hybrid organic–inorganic composite functionalized with Alq3 was used as an emitting layer in an OLED device. The advantage of the spin-coated films is its ease of layer deposition method to replace physical vapor deposition. Investigation of chemical structure of these networks was performed by different techniques including 1H-NMR, FT-IR, DSC and SEM. Results revealed that a silicone based structure was produced in which Alq3 has been attached to silane precursor through amine groups of silane and sulfonic functionality of 8-hydroxyquinoline. Electrical behavior of the samples was measured by cyclic voltammetry method. Photoluminescence and electroluminescence analyses showed that hybrid organic–inorganic Alq3-network can be used in OLED devices to replace conventional Alq3. While the band gap of the pristine Alq3 is 2.70 eV, that of the silane modified Alq3 has shifted to 2.83 eV. This shows a blue shift in emitted color.

A novel solution processable tris(8-hydroxyqu- inolinato)aluminum (Alq3)-containing organic inorganic hybrid material was synthesized from 8-hydroxyquinoline- 5-sulfonic acid and alkoxysilane precursors using a sol-gel method. By this functionalization, Alq3 could be easily deposited on a glass substrate with spin coating deposition method, the structure of which was characterized by nuclear magnetic resonance ( 1 H NMR), Fourier transform infra red spectroscopy, differential scanning calorimetry, scanning electron microscopy and photoluminescence studies. The new hybrid material contained a siloxane network attached to the phenoxide ring showed excitation and emission spectra near the characteristic emission of Alq3 with a little blue shift.

Reflectance Visible/near-infrared spectroscopy was used to analyze the effect of peel on the non-destructive soluble solids content prediction of oranges. The spectra were interpreted and partial least squares model was developed for both intact and peeled oranges at two wavelength ranges of 450–1000 and 700–1000 nm. Results showed that the wavelengths of the main absorbance peaks on the spectra of the intact and peeled samples were the same (p > 0.05). Moreover, the developed models yielded a good prediction accuracy of soluble solids content (2.5 0.05). It was also noted that the effect of peel chemical composition can be ignored in non-destructive spectroscopy of intact citrus for determination of soluble solids content.

The feasibility of reflectance Vis/NIR spectroscopy was investigated for taste characterization of Valencia oranges based on taste attributes including soluble solids content (SSC) and titratable acidity (TA), as well as taste indices including SSC to TA ratio (SSC/TA) and BrimA. The robustness of multivariate analysis in terms of prediction was also assessed. Several combinations of various preprocessing techniques with moving average and Savitzky-Golay smoothing filters, standard normal variate (SNV) and multiplicative scatter correction (MSC) were used before calibration and the models were developed based on both partial least squares (PLS) and principle component regression (PCR) methods. The best models obtained with PLS method had root mean square errors of prediction (RMSEP) of 0.33^oBrix, 0.07%, 1.03 and 0.37, and prediction correlation coefficients (r"p) of 0.96, 0.86, 0.87 and 0.92 for SSC, TA, SSC/TA, and BrimA, respectively. It was concluded that Vis/NIR spectroscopy combined with chemometrics could be an accurate and fast method for nondestructive prediction of taste attributes and indices of Valencia oranges. Moreover, the application of this technique was suggested for taste characterization, directly based on BrimA which is the best index related to fruit flavor rather than determination of SSC or TA alone.

The electroluminescence (EL) and photoluminescence (PL) of five porphyrin compounds have been investigated. Each of the porphyrin derivations were doped with different concentrations in a PVK(polyvinyl carbazole):PBD(2-(4-biphenyl)-5-(4-t-butyl-phenyl)-1,3,4-oxadiazole) blend as the host. The effect of the porphyrin type on the variation of the peak wavelength, FWHM (wavelength peak of emission spectra), CIE (1931 color Space standard) Coordinate, I–V characteristics have been studied in the same host, and the PL and EL spectra for all porphyrins were compared. It has been shown that the electrical and optical properties of the fabricated device can be controlled by altering the structure and concentration of the dopant.

A stable guest-host system was prepared to improve the nonlinear optical (NLO) effects as well as the mechanical and morphological properties of the polymeric host matrices. A hybrid organic-inorganic nano composite synthesized via the sol-gel process in our previous work and Disperse Red 1 (DR1) was utilized as the host and the guest, respectively. Thin films were deposited on glass slides using a dip-coater rig. Dichroism measurements were carried out to gain information on the aggregation of the dye molecules and also the orientation mechanisms. In addition, birefringence studies were performed to determine the desired variations of the refractive indices. The diagrams analyses were especially focused on the changing tendency of three parameters in different samples; the signal level, the rise time and the fall time.