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Perovskite-on-silicon tandem solar cells are a promising candidate to significantly increase the efficiency of PV modules. Despite the fast research progress on material and solar cells aspects, there is still a lack of processes for an industrial module integration of these devices. One aspect hereby is the adaption of encapsulation materials and processes to the requirements of perovskite materials. Process temperatures of about 150 °C are necessary to use well proven, in silicon PV commonly applied encapsulation materials with a high reliability. However, perovskites start to decompose into their components at high temperatures. This limits the encapsulation process temperature, which in turn constraints the choice of encapsulation materials. This work presents an encapsulation process for methylammonium lead iodide (MAPbl3) single junction perovskite solar cells (PSCs) with conventional production tools in glass-glass modules that serves as a model system for perovskite tandem applications. We evaluate the influence of the encapsulation process temperature between 120 °C and 160 °C on the performance of mini modules. The UV-absorbing encapsulation material is processable over the whole investigated temperature regime. We observe a difference in the IV-characteristics between the PSCs encapsulated in the temperature range of 120 °C - 140 °C to those processed at 160 °C. At lower encapsulation temperatures the IV−curves taken 1 h after encapsulation show a pronounced S-shape and no degradation of VOC. ln contrast, the PSCs encapsulated at 160 °C exhibit a VOC decrease of up to 29% compared to the initial measurement shortly after PSC fabrication and no significant S-shape. Both, the S-shape that occurs at low encapsulation temperatures and the VOC loss after encapsulation at 160 °C, are no longer significant after one week of module storage under dark conditions. The presented encapsulation process therefore does not permanently damage the MAPbl3 PSCs even at a standard encapsulation temperature of 160 °C. To ensure long-term operation, we test the fabricated mini modules in a damp heat test at 85 °C and a relative humidity of 85%. We find no significant additional degradation caused by damp heat in 1250 h test duration compared to a reference module stored in ambient air. [ABSTRACT FROM AUTHOR]

Halide based perovskite solar cells (PSCs) have recently shown rapidly rising power conversion efficiencies up to 25.2 % [1], but there are a number of opportunities to improve their photovoltaic parameters. For example, the open current voltage (VOC) maximum of thin film cells cannot be achieved without additional photonic nanostructures, while the optimization of main SC parameters strongly depended from the transport properties of each cell layer and could be received by inclusion of nanostructures. Therefore, we employ Phosphorus doped Silicon nanoparticles (n-Si NPs) for light trapping enhancement and improved charge transfer between meso-TiO2 and MAPbI3 layers of PSCs. We show the efficiency growth from 17.6 to 18.2% via the improvement of VOC. The proposed method for preparing upgraded PSCs is cheap and can be simply implemented to the technological process. [ABSTRACT FROM AUTHOR]

Perovskite solar cells is one of the fast growing research field due to its rapid increase in power conversion efficiency from 3.8% to 25.2%. In this work perovskite nanostructure were used as light sensitizer. Perovskite structures are prepared usually in the nitrogen atmosphere. In this work perovskite was prepared and kept in open air to study the moisture stability of perovskite nanostructure. To fabricate perovskite nanostructure, benzyl ammonium iodide was added as additive to methyl ammonium lead iodide and the mixture was electrospun over Fluorine doped Tin Oxide (FTO) coated glass plate. Prepared structure was characterized by SEM and XRD analysis which confirmed the nanostructure. The fabricated solar cell has the structure FTO/PEDOT: PSS/Perovskite/Ag. The photovoltaic parameters of the fabricated solar cell were extracted and compared. Moisture study of prepared solar cell was taken for 600 hrs. [ABSTRACT FROM AUTHOR]

The photoluminescence increment in chloride doped all-inorganic rubidium lead iodide (RbPbI3) perovskite has been reported. The pristine RbPbI3 perovskite was synthesized by a simple sol gel method and the crystals are found to be polycrystalline in nature having orthorhombic symmetry. Whereas, an increase in diffracting angles and band gap could be observed upon insertion of chloride in the perovskite structure. Moreover, the photoluminescence (PL) characteristics of the pristine perovskite demonstrated near band edge emission with poor intensity. But, an increasing trend of the PL intensity was observed for chloride doped crystals. Interestingly, an emission intensity more than 102 in order was observed when the chloride concentration was 30% with respect to the iodide. Thus, the increment in band gap due to chloride doping makes the RbPbI3 more flexible for wide range of optoelectronic devices. Further, the enhanced emission characteristics of the chloride doped perovskite enriches its implication in optoelectronic devices. Finally, we conclude that the RbPbI3 perovskite could be utilized in various application via optimized incorporation of chloride. [ABSTRACT FROM AUTHOR]

In this work, CsPbI3 and CsPbBr0.5I2.5 were synthesized by the cold sintering method. The structural studies were verified using X-ray diffraction with Rietveld refinement and revealed the orthorhombic phase with Pnma symmetry. Moreover, the crystallite size and the microstrain of the samples reduced with the Br- substitution. Scanning Electron Microscopy showed the regular form of grain size for CsPbI3, but CsPbBr0.5I2.5 shows the dense morphology with voids. The XPS spectra of the materials revealed the constituent’s elemental details. UV-Visible measurements revealed the absorbance spectra of the samples and the bandgap energy from Tauc’s relation is found to be ~ 2.33 eV. [ABSTRACT FROM AUTHOR]

Perovskite solar cells have been intensively investigated for high performance and low-cost solid-state solar cells. Perovskite based-lead materials are commonly used as active material for high power conversion efficiency solar cells. Herein, we report our study on the development of used electrodes car battery as a cheap raw lead material to be converted into lead (II) iodide PbI2 by using simple chemical method. We have successfully obtained PbI2 material with purity higher than 85% and its crystal structure is comparable with that of commercial product. The perovskite CH3NH3PbI3 film was prepared by spin-coating of PbI2 solution and followed by spin-coating two-times of methylamonium iodide (MAI) solution. In this paper, the crystal structure of perovskite film attained from used car battery is shown and compared with that of prepared from commercial PbI2. By utilizing the used car battery into perovskite valuable material for high performance solar cells, we can not only improve the economical value (addedvalue) of wasted car battery but also we can simultaneously save the environment. [ABSTRACT FROM AUTHOR]

Perovskite materials have become great research interest due to their superior properties for high power conversion efficiency (PCE) solar cells. Recently, a PCE above 18% is already achieved using perovskite methylamonium lead iodide (CH3NH3PbI3, MAPbI3) as active material. High quality crystal of perovskite film as active material is very crucial to be controlled for obtaining high PCE with high environmentally stable solar cells. Spin-coating and dip-coating methods are commonly used to prepare perovskite films for solar cells. However, not all lead(II) iodide PbI2 can be completely converted into perovskite which cause low PCE and deteriorate the stability of solar cells. Therefore, a suitable and simple method for obtaining high quality crystal MAPbI3 film is highly needed. Herein, we report our current study on the optical, structural and morphological properties of perovskite CH3NH3PbI3 films prepared by use of two-step spin coating method. By using this method, no PbI2 peak is observed in the XRD pattern of perovskite film which proves that all PbI2 was fully converted into perovskite CH3NH3PbI3. [ABSTRACT FROM AUTHOR]

We have performed the non linear absorption studies on PbI2.2H2O irradiated with UV and IR by using open aperture Z-scan technique The solution of lead iodide di hydrate shows reverse saturable absorption.. Nonlinear absorption coefficient at different fluence values is numerically evaluated. Lead Iodide di hydrate is highly nonlinear due to its high value of nonlinear absorption coefficient. The reverse saturable absorption nature of lead iodide di hydrate makes it suitable for optical limiting applications with low optical limiting threshold. [ABSTRACT FROM AUTHOR]

Hybrid organometal perovskites have been emerged as promising solar cell material and have exhibited solar cell efficiency more than 20%. Thin films of Methylammonium lead iodide CH3NH3PbI3 perovskite materials have been synthesized by two different (one step and two steps) methods and their morphological properties have been studied by scanning electron microscopy and optical microscope imaging. The morphology of the perovskite layer is one of the most important parameters which affect solar cell efficiency. The morphology of the films revealed that two steps method provides better surface coverage than the one step method. However, the grain sizes were smaller in case of two steps method. The films prepared by two steps methods on different substrates revealed that the grain size also depend on the substrate where an increase of the grain size was found from glass substrate to FTO with TiO2 blocking layer to FTO without any change in the surface coverage area. Present study reveals that an improved quality of films can be obtained by two steps method by an optimization of synthesis processes. [ABSTRACT FROM AUTHOR]