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Lead sulfide quantum dots (PbS QDs) are promising candidates for high-performance solar cells due to their tunable bandgaps and low-cost solution processing. However, low carrier mobility and numerous surface defects restrict the performance of the fabricated solar cells. Herein, we report the synthesis of novel PbS-perovskite core-shell QDs to solve the low carrier mobility problem of PbS QDs via a facile hot injection method. CsPbI2Br shell enabled strain-free epitaxial growth on the surface of PbS QDs because of 98% lattice match. Our results demonstrate a significant improvement in the photoluminescence and stability of the synthesized PbS-CsPbI2Br QDs upon shell formation, attributed to the effective suppression of surface defects by the epitaxial shell of CsPbI2Br. As a result, the obtained solar cell based on PbS-CsPbI2Br core-shell QD exhibits a power conversion efficiency (PCE) of 8.43%, two times higher than that of pristine PbS QDs. Overall, the construction of PbS-CsPbI2Br core-shell structures represent a promising strategy for advancing the performance of PbS QDs-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

All‐inorganic CsPbI3 perovskite is a promising emitter for deep‐red light‐emitting diodes (LEDs). However, presently fabricated CsPbI3 polycrystalline films are composed of island‐like polycrystals, encountering the problems of serious interface current leakage and low‐efficiency carrier radiative recombination. Here, a CsPbI3‐xBrx quantum dots (QDs) matrix encapsulated CsPbI3 polycrystal film is reported to address the low‐efficiency issue of island‐like CsPbI3 polycrystalline film applied in deep‐red LEDs. The developed QDs matrix encapsulation strategy has two benefits. One is the filling of void space in the island‐like CsPbI3 polycrystal film to suppress the interface current leakage. The other more important benefit is utilizing the strong carrier confinement effect of QDs to strengthen the formation of excitons in the composite film and thus improve the electroluminescence efficiency. Moreover, interesting grain growth is found between CsPbI3‐xBrx QDs and CsPbI3 polycrystals, which further enhances the exciton transfer effect brought by the QDs matrix and optoelectronic properties of the fabricated composite films. Based on the obtained high‐quality QDs/polycrystal composite films, efficient and bright deep‐red LEDs are achieved with a peak external quantum efficiency of 15.24% and a maximum luminance of 3691 cd m−2. [ABSTRACT FROM AUTHOR]

Two new salts [4-ClBzPid]2[Ni(mnt)2](1) and [4-ClBzPid][Ni(mnt)2](2)([4-ClBzPid]+= 1-(4′-chlorobenzyl)-piperidinium and mnt2−= maleonitriledithiolate) were synthesized and characterized by elemental analyses, IR, UV-Vis, ESI-MS, single crystal X-ray diffraction, and magnetic measurements. The [Ni(mnt)2]2−anions of1form a one-dimensional side-by-side structure via N···N short interaction, whereas the [Ni(mnt)2]−anions in2form a one-dimensional face-to-face column through short inter-molecular Ni···Ni, Ni···S, and S···S interactions in which the Ni(III) ions form a nonuniform magnetic chain with the Ni···Ni distances of 3.676 Å and 4.357 Å. Furthermore, the [4-ClBzPid]+cations in1stack into 1D columns via C–H···Cl and Cl···Cl interactions, while the cations (C) and [Ni(mnt)2]−anions (A) of2stack into a 1D column with a A-CC-A-CC-A sequence by N···π and N–H···N weak interactions. Some other weak interactions including C–H···N and C–H···Ni hydrogen bonds result in the forming of a 3D network. Magnetic susceptibility measurements in the temperature range 2 to 300 K show that two salts exhibit diamagnetic behavior. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Three molecular magnets containing [Ni(mnt)2]− anion were successfully obtained. [•] The anions and the cations in 1 and 3 stack into segregated columns. [•] The Ni(III) ions of 1 and 3 form a alternating 1D zigzag magnetic chain. [•] The [Ni(mnt)2]− anions of 2 form a dimer. [•] Compounds 1 and 3 show interesting characteristic of spin-gap. [Copyright &y& Elsevier]

Perovskite light-emitting diodes (PeLEDs) are promising for next-generation high-definition displays. One of the keys to achieving high performance PeLEDs lies in how to fabricate crystalline and dense perovskite films. However, there exist challenges to directly grow well-crystallized CsPbBr 3 nanocrystal thin films on transport layers due to low solubility in solvents and fast precipitation of all-inorganic CsPbBr 3 , and the corresponding bright, efficient, and stable green PeLEDs have rarely been reported. Herein, we report an efficient strategy to prepare well-crystallized and dense CsPbBr 3 nanocubes for ultrabright and efficient green PeLEDs. We introduce sulfobetaine zwitterion as crystallization control agent and strontium fluoride nanocrystals as nucleation seeds to grow high-quality CsPbBr 3 nanocube films. Eventually, the CsPbBr 3 films enable green PeLEDs with a maximum luminance of 162 767 cd m -2 and a champion external quantum efficiency of 21.3% along with a narrow spectral line width of ∼14.7 nm, representing state-of-the-art performances in green PeLEDs.

Objective: To investigate the effect of local application of bFGF combined with sucralfate on the cell proliferation during continuous tissue expansion (CTE)., Methods: Nine white pigs were selected to undergo the continuous tissue expansion in this study and treated with bFGF and sucralfate, respectively as the following groups: group 1 with both bFGF and sucralfate, group 2 only with bFGF, group 3 with only sucralfate, and group 4 with saline as control. Fifteen samples were taken in each pig for immunohistochemistry analysis 1-14 days and 6 weeks after the operation., Results: In the group with both bFGF and sucralfate, the epidermic basal cells proliferated significantly after the operation and reached top level in 3 days, which was statistical higher than the control group, but the multiplication of basal cell was the lowest 14 days after the operation, still more than the control group. In dermal layer, proliferation of fibroblasts, vessel endothelial cells, hair follicles epidermic cells and sweat gland epicytes was also significant higher in the group with both bFGF and sucralfate than that the control group and reached top level 7 day after the operation, but the proliferation of cells decreased obviously 14 days after the operation, still higher than the control group. The mitotic activity of cells returned to the basal level in 42 days. There were no significant differences among the group 2, group 3 and group 4., Conclusion: Local application of both bFGF and sucralfate could be more effect to induce cells multiplication during early skin expansion to facilitate the growth of neoformed skin soft tissue.

Objective: To investigate the effect of local application of bFGF and sucralfate during continuous tissue expansion (CTE)., Methods: CTE combined with local administration of bFGF and sucralfate was used in twelve patients with scar and nasal tip defects. Twenty three expanders were placed in the subcutaneous pockets through intralesion short incisions. Continuous expansion began at 1-3 days after expander implantation. The histomorphological changes and epidermal cell proliferation were observed. The clinical results were investigated., Results: The average inflation time was 8.9 days. The average interval of the two operations was 13.5 days. The average hospitalization was 28.4 days. The average immediate stretch-back rate of the expanded skin was 25.7%. The clinical results were satisfactory without any complications. Histological examinations showed that the epidermal, granular and spinous layer became thicker. The basal cells increased significantly. The dermis thinned slightly and the collagen fibers became thicker. The elastic fiber regenerated significantly. Fibroblast and capillary density increased obviously. The immunohistochemistry analysis showed that the proliferation of epidemic basal cells was significant postoperatively., Conclusion: Local application of exogenous bFGF and sucralfate during CTE was feasible in patients. It could accelerate tissue expansion and improve the quality of expanded skin flap.

Objective: To investigate the effect of local application of basic fibroblast growth factor (bFGF) and sucralfate on the skin tissue structure after expansion., Methods: Continuous tissue expansion (CTE) experimental animal model was made with constant pressure pump in nine white pigs. The bFGF and sucralfate were perfused between tissue and tissue expander. Both bFGF and sucralfate were injected in group I, both bFGF and normal saline in group II, only sucralfate in group III, and normal saline in group IV as control group. The samples were took from each pig for histomorphological assessment on the 3rd day and 6th week after expansion., Results: Compared with control group, epidermal, granular spinous and basal cell thickness increased significantly (P < 0.05) in group I; in dermal layer, dermal thickened slightly and the collagen fibers became thicker and orderly; the elastic fiber regenerated significantly; the density of fibroblasts and capillaries significantly increased (P < 0.05) in group I. The collagen fibers were broken on the 3rd day and 6th week after expansion in control group. However, the thickness of the fibrous capsule layer was similar in each group., Conclusion: Local application of exogenous bFGF and sucralfate combined with CTE can greatly promote the skin growth. It can accelerate the tissue expansion.