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Inorganic perovskite absorbers are promising candidates for next-generation photovoltaics due to their good thermal and light stabilities. Halide-mixed CsPbIxBr3−x reach a compromise between its structural tolerance and absorption edge, yet the power conversion efficiencies (PCEs) of the asfabricated cells can be considerably limited by the nonideal quality of solution-processed films. Here we demonstrated a fumigation strategy on colloidal perovskite films using dual-O-donor ethyl acetate (EA). By in-situ monitoring this stage with grazing-incidence wide-angle X-ray scattering technology, we reveal that EA fumigation would impose ripening barrier on colloidal inorganic perovskites and hence slow down the nucleation rate, leading to an intermediate state for processing high-crystallinity and oriented perovskite films with improved photophysical properties. An optimized PCE of 16.6% was finally yielded upon wide-bandgap (1.9 eV) perovskite absorber.

Cesium-based all-inorganic perovskite absorbers have attracted increasing attention due to their superior thermal stability, compared to their organic–inorganic counterparts. Up to now, it is a challenge to fabricate high-efficiency all-inorganic perovskite solar cells (PSCs) with low defect densities. Herein, we used bivalent metal chloride salts (SrCl2 and NiCl2) to optimize CsPbI2Br films. The experimental results indicate that this method could deliver high-quality films with improved electronic property. As a result, the champion device based on the 0.01 M SrCl2–doped CsPbI2Br film achieved a power conversion efficiency (PCE) of 16.07% with a high open voltage (VOC) of 1,322 mV, which is about 18% higher than that of the pristine device.

Background: This study evaluated the effectiveness and safety of bloodletting (BL) at ear-apex (EX-HN6) as an adjunctive therapy to eye drops for stye. Methods: This study systematically searched electronic databases from inception to March 1, 2020 in PUBMED, EMBASE, Cochrane Library, China National Knowledge Infrastructure, Chinese Scientific Journals Full-text Database, and WanFang Database. All potential randomized controlled trials (RCTs) investigating the effectiveness and safety of BL at EX-HN6 as an adjunctive therapy to eye drops for stye were included in this study. Study quality of all included studies was assessed by Cochrane Risk of Bias Assessment Tool. RevMan 5.3 software was used for statistical analysis and meta-analysis performance. Results: A total of 11 RCTs, involving 1718 subjects, were included in this study. Results showed that BL at EX-HN6 as an adjunctive therapy to eye drops was superior to the eye drops alone in enhancing total effectiveness rate (risk ratio [RR] 1.21, 95% confidence intervals [CIs] [1.11, 1.32], I2 = 79%), and total cure rate (RR 1.28, 95% CIs [1.14, 1.43], I2 = 69%). After removing two studies, results of subgroup analysis still showed significant improvements in total effectiveness rate (RR 1.13, 95% CIs [1.08, 1.18], I2 = 0%), and total cure rate (RR 1.16, 95% CIs [1.08, 1.24], I2 = 0%). No data of adverse reactions was reported in primary trials, thus, this study did not analyze adverse reactions of BL at EX-HN6 as an adjunctive therapy to eye drops for stye. Conclusion: BL at EX-HN6 as an adjunctive therapy to eye drops may benefit stye. However, high-quality RCTs addressing on this issue is still needed to warrant the findings of this study.

Organometallic halide perovskite solar cells (PSCs) are rapidly evolving as the promising photovoltaic technologies with high record efficiency over 24%. The inorganic p-type semiconductor NiOx is extensively used as important hole transport layers for the realization of stable and hysteresis-free solar cells due to their good electronic properties, facile fabrication, and excellent chemical endurance. However, the critical issues of NiOx films including poor intrinsic conductivity and mismatched band alignment limit further improvement of the device performance. Herein, it is demonstrated that a versatile alkaline earth metal (Mg, Ca, Sr, and Ba) doping strategy can effectively engineer the electronic properties of NiOx contacts in inverted planar PSCs. Alkaline earth metal doping can deepen valence band maximum and enhance the hole conductivity of NiOx films, which better aligns the energy band in solar cells. The champion device based on Sr-doped NiOx films attains a power conversion efficiency of 19.49% with a high open-circuit voltage (VOC) of 1.14 V for NiOx-based CH3NH3PbI3 devices. The resulted device shows negligible hysteresis and high stability as well. This finding provides a systematic doping strategy to further improve the performance of inverted planar PSCs.