In this work, the numerical simulation of CH3NH3PbI3 perovskite solar cells was undertaken using the scaps-1d solar cell capacitance simulator software. A perovskite solar cell was simulated for best efficiency by replacing the traditional compact TiO2 layer with CdS (i.e., a hole-blocking layer) because CdS layers have been shown to possess a greater photostability than TiO2 with continuous illumination of sunlight. With the view of optimizing the device fabrication of perovskite/CdS thin-film solar cell (TFSC) for maximum efficiency, the perovskite/CdS TFSC structure was optimized theoretically using scaps-1d, which is possible because the perovskite layer has the same configuration and an excitation type as CdTe, copper-indium-gallium-selenide, and other inorganic semiconductor solar cells. Solar cell performance is highly dependent on the layer parameters, and so the effect that absorber thickness, bulk defects, and interface defects have on the device performance was studied and the device was optimized. Further, the effect that atmospheric conditions have on device performance was studied by varying the temperature and illumination density, and the optimum performance was found. After these optimizations, the simulation results show that a perovskite thickness of 500 nm yields an efficiency of 23.83% with a high open-circuit voltage of 1.37 V. These results for this absorber thickness is in good agreement with reports of experimental results for this device.

Doping of semiconductors in a controlled mannner have paramount technological importance as far as the optical and electronic properties of the devices are concerned. Hybrid organic-inorganic perovskites (HOPs) as intrinsic semiconductors have sensational properties required for both the solar photovoltaics and perovskite light emitting diodes. However, undoped and complexity in the dpoing process of HOPs have limited their exploitation in the field of elcronics. In this papper we present the synthesis of HOP semiconductor (CH3NH3PbI3) doped in Pb2+ position by Cd2+. We studied the effect of the incorporation of Cd2+ into the crystalline structure and analysed the changes in the properties like crystal structure, optical absorption and the surface morphology. The structure of HOPs confirmed by X-ray diffraction analysis is tetragonal perovskite type. It can be found that the crystallinity of the samples was enhanced with the doping concentration as the intensity of diffraction peaks were observed to increase with doping. The absorption spectra as obtained from UV-Visible spectrophotometry and Tauc plot analysis indicated that the band gap observed (1.73 eV) is direct type and gets reduced to 1.67 eV with the doping concentration. The red shift may be due to the increase in the size of nanocrystalline material with doping.

First principle calculations with highly precise spin-polarized density functional theory (DFT) have been performed to study the structural stability, mechanical and magneto-electronic properties of cubic perovskite BaBkO3. The properties were studied under the generalized gradient approximation (GGA) and onset Coulomb interaction by WEIN2k package. The DFT and analytically calculated values of Goldschmidt tolerance (GT) factor in addition to stable-phase optimization show stability of the present material in the ferromagnetic cubic phase with a higher magnetic moment of 7 mu B. This is because the nature of magnetism of 5f actinide materials (l = 3) is governed by the large spin-orbit interaction and the hybridization of 5f electron orbitals with other states. The value of exchange and correlation potential were treated with different approximations: GGA and GGA + U calculations. Contribution of electronic states was studied through total and partial density of states using GGA and GGA + U approach. GGA + U calculations reveal an indirect band gap of 3.15 eV for BaBkO3 in the spin down channel supporting the half metallic nature and spin-polarized electronic band structure encourages complete spin polarization of the material with metallic character in spin up state. Mechanical properties like stability, stiffness, hardness, brittleness and ductility were discussed on the basis of elastic parameters obtained. The oxide perovskite BaBkO3 exhibit higher value of Seebeck coefficient and power factor at room temperature with a value of 150 mu VK-1 and 5.1 x 10(12) mu Wcm(-1) K(-2)s(-1) respectively. The properties of half-metallicity and higher Seebeck coefficient makes this material a promising candidate for thermoelectric and spintronic device applications. (C) 2018 Published by Elsevier B.V.

In this work, we design and analyze the Cu(In, Ga)Se2 (CIGS) solar cell using simulation software "Solar Cell Capacitance Simulator in One Dimension (SCAPS-1D)". The conventional CIGS solar cell uses various layers, like intrinsic ZnO/Aluminium doped ZnO as transparent oxide, antireflection layer MgF2, and electron back reflection (EBR) layer at CIGS/Mo interface for good power conversion efficiency. We replace this conventional model by a simple model which is easy to fabricate and also reduces the cost of this cell because of use of lesser materials. The new designed model of CIGS solar cell is ITO/CIGS/OVC/CdS/Metal contact, where OVC is ordered vacancy compound. From this simple structure, even at very low illumination we are getting good results. We simulate this CIGS solar cell model by varying various physical parameters of CIGS like thickness, carrier density, band gap and temperature.

In this paper, we numerically investigate CdTe/CdS PV cell properties using a simulation program Solar Cell Capacitance Simulator in 1D (SCAPS-1D). A simple structure of CdTe PV cell has been optimized to study the effect of temperature, absorber thickness and work function at very low incident power. Objective of this research paper is to build an efficient and cost effective solar cell for portable electronic devices such as portable computers and cell phones that work at low incident power because most of such devices work at diffused and reflected sunlight. In this report, we simulated a simple CdTe PV cell at very low incident power, which gives good efficiency.