METHOD FOR SINGLE CRYSTAL GROWTH OF PHOTOVOLTAIC PEROVSKITE MATERIAL AND DEVICES

Systems and methods for perovskite single crystal growth include using a low temperature solution process that employs a temperature gradient in a perovskite solution in a container , also including at least one small perovskite single crystal , and a substrate in the solution upon which substrate a perovskite crystal nucleates and grows , in part due to the temperature gradient in the solution and in part due to a temperature gradient in the substrate . For example , a top portion of the substrate external to the solution may be cooled

SYSTEMS AND METHODS FOR SCALABLE PEROVSKITE DEVICE FABRICATION

Continuous processes for fabricating a perovskite device are described that include forming a perovskite layer or film on a substrate using a linear deposition device , and optionally using a conductive tape lamination process to form an anode or a cathode layer on the perovskite device

Chloride Incorporation Process in CH\u3csub\u3e3\u3c/sub\u3eNH\u3csub\u3e3\u3c/sub\u3ePbI\u3csub\u3e3-x\u3c/sub\u3eCl\u3csub\u3ex\u3c/sub\u3e Perovskites via Nanoscale Bandgap Maps

CH3NH3PbI3-xClx perovskites enable fabrication of highly efficient solar cells. Chloride ions benefit the morphology, carrier diffusion length and stability of perovskite films; however, whether those benefits stem from the presence of Cl− in the precursor solution or from their incorporation in annealed films is debated. In this work, the photothermal induced resonance (PTIR), an in situ technique with nanoscale resolution, is leveraged to measure the bandgap of CH3NH3PbI3-xClx films obtained by a multicycle coating process that produces high efficiency (≈16 %) solar cells. Because chloride ions modify the perovskite lattice, thereby widening the bandgap, measuring the bandgap locally yields the local chloride content. After a mild annealing (60 min, 60°C) the films consist of Cl-rich (x \u3c 0.3) and Cl-poor phases that, upon further annealing (110 °C), evolve into a homogenous Cl-poorer (x \u3c 0.06) phase, suggesting that methylammonium-chrloride is progressively expelled from the film. Despite the small chloride content, CH3NH3PbI3-xClx films show better thermal stability up to 140 °C with respect CH3NH3PbI3 films fabricated with the same methodology

Thumb function and appearance following treatment of Wassel type III duplication thumbs

AbstractObjectiveThe purpose of our study is to evaluate thumb function and appearance after surgical correction of Wassel type III thumbs polydactyly.MethodsWe have reconstructed 28 cases of Wassel type III duplication thumbs, in which the duplicated digits were equal or almost equal in size by ablation of a radial digit. The extra thumb is osteotomized at the bifurcation level and excised except for the distal bone fragment supporting the nail bed and fillet flap. Meanwhile, the nail of the retained thumb should be reserved completely, and if the nail has relatively poor appearance it should be repaired by nail lengthening surgery. Eighteen cases were followed up for more than 3 years and were available for assessment using the Japanese Society for Surgery of the Hand evaluation form. The average age at follow-up was 5 years. The size of the nail and distal phalanx was measured to assess the growth of the thumb.ResultsAn average functional point was 12 points (maximum 14 points) and the cosmetic score averaged 3.6 (maximum 4 points) after the assessment. Slightly small nails without a central ridge were deemed acceptable. Second revision surgery is seldom. Long-term results after surgical reconstruction for duplication thumbs were excellent, and all patients and parents were satisfied with the cosmetic and functional results.ConclusionsThis procedure is a helpful and effective way to provide functional and aesthetical thumb for Wassel type III duplication thumbs

INSULATING TUNNELING CONTACT FOR EFFICIENT AND STABLE PEROVSKITE SOLAR CELLS

Perovskite-based photoactive devices, such as solar cells, include an insulating tunneling layer inserted between the perovskite photoactive material and the electron collection layer to reduce charge recombination and concomitantly provide water resistant properties to the device

Improving the sensitivity of a near-infrared nanocomposite photodetector by enhancing trap induced hole injection

We report the enhancement of the photoconductive gain of nanocomposite near-infrared photodetectors by a zinc oxide nanoparticles (ZnO NPs) rich surface at the nanocomposite/cathode interface. An argon plasma etching process was used to remove polymer at the surface of nanocomposite films, which resulted in a ZnO NPs rich surface. The other way is to spin-coat a thin layer of ZnO NPs onto the nanocomposite layer. The ZnO NPs rich surface, which acts as electron traps to induce secondary hole injection under reverse bias, increased hole injection, and thus the external quantum efficiency by 2–3 times. The darkcurrent declined one order of magnitude simultaneously as a result of etching the top nanocomposite layer. The specific detectivity at 800 nm was increased by 7.4 times to 1.11x1010 Jones due to the simultaneously suppressed noise and enhanced gain

Improving the sensitivity of a near-infrared nanocomposite photodetector by enhancing trap induced hole injection

We report the enhancement of the photoconductive gain of nanocomposite near-infrared photodetectors by a zinc oxide nanoparticles (ZnO NPs) rich surface at the nanocomposite/cathode interface. An argon plasma etching process was used to remove polymer at the surface of nanocomposite films, which resulted in a ZnO NPs rich surface. The other way is to spin-coat a thin layer of ZnO NPs onto the nanocomposite layer. The ZnO NPs rich surface, which acts as electron traps to induce secondary hole injection under reverse bias, increased hole injection, and thus the external quantum efficiency by 2–3 times. The darkcurrent declined one order of magnitude simultaneously as a result of etching the top nanocomposite layer. The specific detectivity at 800 nm was increased by 7.4 times to 1.11x1010 Jones due to the simultaneously suppressed noise and enhanced gain