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Increasing the power conversion efficiency (PCE) of the two‐dimensional (2D) perovskite‐based solar cells (PVSCs) is really a challenge. Vertical orientation of the 2D perovskite film is an efficient strategy to elevate the PCE. In this work, vertically orientated highly crystalline 2D (PEA)2(MA)n–1PbnI3n+1 (PEA= phenylethylammonium, MA = methylammonium, n = 3, 4, 5) films are fabricated with the assistance of an ammonium thiocyanate (NH4SCN) additive by a one‐step spin‐coating method. Planar‐structured PVSCs with the device structure of indium tin oxide (ITO)/poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate)/(PEA)2(MA)n–1PbnI3n+1/[6,6]‐phenyl‐C61‐butyric acid methyl ester/bahocuproine/Ag are fabricated. The PCE of the PVSCs is boosted from the original 0.56% (without NH4SCN) to 11.01% with the optimized NH4SCN addition at n = 5, which is among the highest PCE values for the low‐n (n < 10) 2D perovskite‐based PVSCs. The improved performance is attributed to the vertically orientated highly crystalline 2D perovskite thin films as well as the balanced electron/hole transportation. The humidity stability of this oriented 2D perovskite thin film is also confirmed by the almost unchanged X‐ray diffraction patterns after 28 d exposed to the moisture in a humidity‐controlled cabinet (Hr = 55 ± 5%). The unsealed device retains 78.5% of its original PCE after 160 h storage in air atmosphere with humidity of 55 ± 5%. The results provide an effective approach toward a highly efficient and stable PVSC for future commercialization.

Herein we present a new structural design of hole-transporting material, Trux-OMeTAD, which consists of a C3h Truxene-core with arylamine terminals and hexyl side-chains. This planar, rigid, and fully conjugated molecule exhibits excellent hole mobility and desired surface energy to the perovskite uplayer. Perovskite solar cells fabricated using the p-i-n architecture with Trux-OMeTAD as the p-layer, show a high PCE of 18.6% with minimal hysteresis.

Background Genetically-engineered pigs could provide a source of kidneys for clinical transplantation. The two longest kidney graft survivals reported to date have been 136 days and 310 days, but graft survival >30 days has been unusual until recently. Methods Donor pigs (n=4) were on an α1,3-galactosyltransferase gene-knockout (GTKO)/human complement-regulatory protein (CD46) background (GTKO/CD46). In addition, the pigs were transgenic for at least one human coagulation-regulatory protein. Two baboons received a kidney from a 6-gene pig (Group A) and two from a 3-gene pig (Group B). Immunosuppressive therapy was identical in all 4 cases, and consisted of anti-thymoglobulin (ATG) + anti-CD20mAb (induction) and anti-CD40mAb + rapamycin + corticosteroids (maintenance). Anti-TNF-α and anti-IL-6R mAbs were administered to reduce the inflammatory response. Baboons were followed by clinical/laboratory monitoring of immune/coagulation/inflammatory/physiological parameters. At biopsy or euthanasia, the grafts were examined by microscopy. Results The two Group A baboons remained healthy with normal renal function >7 and >8 months, respectively, but then developed infectious complications. However, no features of a consumptive coagulopathy, e.g., thrombocytopenia, reduction of fibrinogen, or of a protein-losing nephropathy were observed. There was no evidence of an elicited anti-pig antibody response, and histology of biopsies taken at approximately 4, 6, and 7 months and at necropsy showed no significant abnormalities. In contrast, both Group B baboons developed features of a consumptive coagulopathy and required euthanasia on day 12. Conclusions The combination of (i) a graft from a specific 6-gene genetically-modified pig, (ii) an effective immunosuppressive regimen, and (iii) anti-inflammatory therapy prevented immune injury, a protein-losing nephropathy, and coagulation dysfunction for >7 months. Although the number of experiments is very limited, our impression is that expression of human endothelial protein C receptor (+/− CD55) in the graft is important if coagulation dysregulation is to be avoided.

In this review, we first highlighted recent progress in high-performance perovskite solar cells (PVSCs) with a discussion of the fabrication methods and PVSCs-based tandem solar cells. Furthermore, the stability issue of PVSCs and strategies to improve material and device stability have been discussed, and finally, a summary of the recent progress in lead-free perovskites has been presented.

Vertically oriented highly crystalline 2D layered (BA) (MA) Pb I (BA = CH (CH ) NH , MA = CH NH , n = 3, 4) perovskite thin-films are fabricated with the aid of ammonium thiocyanate (NH SCN) additive through one-step spin-coating process. The humidity-stability of the film is certified by the almost unchanged X-ray diffraction patterns after exposed to humid atmosphere (H = 55 ± 5%) for 40 d. The photovoltaic devices with the structure of indium tin oxide(ITO)/poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate)/(BA) (MA) Pb I (n = 3,4)/[6,6]-phenyl-C -butyric acid methyl ester/Bathocuproine/Ag are fabricated. The devices based on (BA) (MA) Pb I perovskite (n = 3) with the precursor composition of BAI:methylammonium iodide:PbI :NH SCN = 2:2:3:1 (by molar ratio) show an averaged power conversion efficiency (PCE) of 6.82%. In the case of (BA) (MA) Pb I (n = 4), a higher PCE of 8.79% is achieved. Both of the unsealed devices perform unique stability with almost unchanged PCE during the period of storage in purified N glove box. This work provides a simple and effective method to enhance the efficiency of the 2D perovskite solar cell.

A version of the fundamental mean-square convergence theorem is proved for stochastic differential equations (SDEs) in which coefficients are allowed to grow polynomially at infinity and which satisfy a one-sided Lipschitz condition. The theorem is illustrated on a number of particular numerical methods, including a special balanced scheme and fully implicit methods. The proposed special balanced scheme is explicit and its mean-square order of convergence is 1/2. Some numerical tests are presented.Key words. SDEs with nonglobally Lipschitz coefficients, numerical integration of SDEs in the mean-square sense, balanced methods, fully implicit methods, strong convergence, almost sure convergence

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