Perovskite (structure)

About: Perovskite (structure) is a research topic. Over the lifetime, 51482 publications have been published within this topic receiving 1541750 citations.

A low viscosity, low boiling point, clean solvent system for the rapid crystallisation of highly specular perovskite films

Abstract: Perovskite-based photovoltaics have, in recent years, become poised to revolutionise the solar industry. While there have been many approaches taken to the deposition of this material, one-step spin-coating remains the simplest and most widely used method in research laboratories. Although spin-coating is not recognised as the ideal manufacturing methodology, it represents a starting point from which more scalable deposition methods, such as slot-dye coating or ink-jet printing can be developed. Here, we introduce a new, low-boiling point, low viscosity solvent system that enables rapid, room temperature crystallisation of methylammonium lead triiodide perovskite films, without the use of strongly coordinating aprotic solvents. Through the use of this solvent, we produce dense, pinhole free films with uniform coverage, high specularity, and enhanced optoelectronic properties. We fabricate devices and achieve stabilised power conversion efficiencies of over 18% for films which have been annealed at 100 °C, and over 17% for films which have been dried under vacuum and have undergone no thermal processing. This deposition technique allows uniform coating on substrate areas of up to 125 cm2, showing tremendous promise for the fabrication of large area, high efficiency, solution processed devices, and represents a critical step towards industrial upscaling and large area printing of perovskite solar cells.

Constructing heterojunctions by surface sulfidation for efficient inverted perovskite solar cells

Abstract: A stable perovskite heterojunction was constructed for inverted solar cells through surface sulfidation of lead (Pb)–rich perovskite films. The formed lead-sulfur (Pb-S) bonds upshifted the Fermi level at the perovskite interface and induced an extra back-surface field for electron extraction. The resulting inverted devices exhibited a power conversion efficiency (PCE) >24% with a high open-circuit voltage of 1.19 volts, corresponding to a low voltage loss of 0.36 volts. The strong Pb-S bonds could stabilize perovskite heterojunctions and strengthen underlying perovskite structures that have a similar crystal lattice. Devices with surface sulfidation retained more than 90% of the initial PCE after aging at 85°C for 2200 hours or operating at the maximum power point under continuous illumination for 1000 hours at 55° ± 5°C. Description Inverted solar cells’ surface sulfidation Perovskite solar cells (PSCs) with high power conversion efficiency (PCE) and stability have been reported in regular n-i-p devices, but inverted p-i-n PSCs that could be easier to use in tandem solar cells usually have lower PCEs (22 to 23%) Li et al. sulfurized a lead-rich layer with hexamethyldisilathiane, and the lead-sulfur bonds shifted the Fermi level of perovskite-transporter layer interface to create an electric field that enhanced electron extraction. The inverted PSCs had PCEs >24%, and the strong lead-sulfur bonds helped to maintain >90% of this efficiency during illuminated operation for 1000 hours at 55°C and after dark aging at 85°C for 2200 hours. —PDS Surface sulfidation of perovskite film increases its stability and improves electron extraction through band bending.

A model for fatigue in ferroelectric perovskite thin films

Abstract: An analytic expression in closed form is given for “fatigue,” the dependence of P(N), the switched charge per unit area P versus switching event number N, in ABO3 perovskite structure ferroelectric thin films is given. The analysis is based upon Arlt’s model for fatigue in bulk perovskites, which involves preferential electromigration of oxygen vacancies to sites parallel to the electrode–ferroelectric interface plane, together with some arguments by Brennan on the effectiveness of such defect planes in pinning domain walls. The model is applied to PZT/Pt with no adjustable parameters and yields in complete agreement with experimental data the dependence of P(N) at different frequencies, different voltages, and different temperatures. Notably, unlike other proposals in the literature, the model does not involve any charge injection from the electrodes.

Enhanced Optical and Electrical Properties of Polymer-Assisted All-Inorganic Perovskites for Light-Emitting Diodes.

Abstract: Highly bright light-emitting diodes based on solution-processed all-inorganic perovskite thin film are demonstrated. The cesium lead bromide (CsPbBr3 ) created using a new poly(ethylene oxide)-additive spin-coating method exhibits photoluminescence quantum yield up to 60% and excellent uniformity of electrical current distribution. Using the smooth CsPbBr3 films as emitting layers, green perovskite-based light-emitting diodes (PeLEDs) exhibit electroluminescent brightness and efficiency above 53 000 cd m-2 and 4%: a new benchmark of device performance for all-inorganic PeLEDs.