semiconductor nanorods are important for numerous applications ranging from optics and electronics to biology, yet the direct synthesis of high-quality metal halide perovskite nanorods remains a challenge. Here, we develop an intermediate monomer reservoir synthetic strategy to realize the controllable growth of uniform and low-defect CsPbBr 3 perovskite nanorods. Intermediates composed of CsPb 2 Br 5 and Cs 3 In 2 Br 9 are obtained through the substitution of Pb 2+ with In 3+ cations in the template of CsPbBr 3 nanocubes and act as a precursor reservoir to gradually release monomers, ensuring both the slow growth rate and low defects of nanorods. We have used branched tris(diethylamino)phosphine as a ligand, which not only has unequal binding energies with different crystal faces to promote the orientation growth but also provides strong steric hindrance to shield the nanorods in solution. Because of minor amount of defects and an effective ligand passivation, in addition to significantly enhanced stability, the perovskite nanorods show a high photoluminescence quantum yield of up to 90% and exhibit a net mode gain of 980 cm −1 , the latter being a record value among all the perovskite materials. An extremely low amplified spontaneous emission threshold of 7.5 μJ cm −2 is obtained under excitation by a nanosecond laser, which is comparable to that obtained using femtosecond lasers in other recent studies.

Sustainable future energy scenarios require significant efficiency improvements in both electricity generation and storage. High-temperature solid oxide cells, and in particular carbon dioxide electrolysers, afford chemical storage of available electricity that can both stabilize and extend the utilization of renewables. Here we present a double doping strategy to facilitate CO2 reduction at perovskite titanate cathode surfaces, promoting adsorption/activation by making use of redox active dopants such as Mn linked to oxygen vacancies and dopants such as Ni that afford metal nanoparticle exsolution. Combined experimental characterization and first-principle calculations reveal that the adsorbed and activated CO2 adopts an intermediate chemical state between a carbon dioxide molecule and a carbonate ion. The dual doping strategy provides optimal performance with no degradation being observed after 100 h of high-temperature operation and 10 redox cycles, suggesting a reliable cathode material for CO2 electrolysis.

Nanobactericides represent one of the most efficient and promising strategies for eliminating bacterial infection considering the increasing resistance threats of conventional antibiotics. Black phosphorus (BP) is the most exciting postgraphene layered 2D nanomaterial with convincing physiochemical properties, yet the study of BP‐based antibiotics is still in its infancy. Here, a compact silver nanoparticle (AgNP)–doped black phosphorus nanosheet (BPN) is constructed to synergistically enhance solar disinfection through the promoted reactive oxygen species (ROS) photogeneration, which is attributed to the improved electron–hole separation and recombination of BPNs as revealed from the systematic experimental studies. An in‐depth density functional theory (DFT) calculation confirms that the integrated AgNPs provide a preferred site for facilitating the adsorption and activation of O2, thus promoting the more efficient and robust ROS generation on BPN–AgNP nanohybrids. Besides the enhanced photoinduced ROS, the anchored AgNPs simultaneously lead to a dramatically increased affinity toward bacteria, which facilitates a synergetic pathogen inactivation. Significantly, the convincing antimicrobial BPN–AgNP contributes to the prominent wound healing and antimicrobial ability in vivo with minimized biological burden. This sophisticated design of new 2D nanohybrids opens a new avenue for further exploiting BP‐based nanohybrids in portable bandage and broad‐spectrum disinfection applications.

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Hydrogen‐bonded organic frameworks (HOFs) are a rising class of promising proton‐conducting materials. However, they always suffer from the inherent contradiction between chemical stability and proton conduction. Herein, inspired by the self‐assembly of lipid bilayer membranes, a series of aminomethylphosphonic acid‐derived single‐component HOFs are successfully developed with different substituents attached to the phosphonate oxygen group. They remain highly stable in strong acid or alkaline water solutions for one month owing to the presence of charge‐assisted hydrogen bonds. Interestingly, in the absence of external proton carriers, the methyl‐substituted phosphonate‐based HOF exhibits a very high proton conductivity of up to 4.2 × 10−3 S cm−1 under 80 °C and 98% relative humidity. This value is not only comparable to that of HOFs consisting of mixed ligands but also is the highest reported in single‐component HOFs. A combination of single‐crystal structure analysis and density functional theory calculations reveals that the high conductivity is attributed to the strengthened H‐bonding interactions between positively charged amines and negatively charged phosphonate groups in the channel of bio‐inspired HOFs. This finding demonstrates that the well‐defined molecular structure of proton conductors is of great importance in the precise understanding of the relationship between structure and property.

Herein we employed a first-principles method based on density functional theory to investigate the surface energy and growth kinetics of wurtzite nanoplatelets to elucidate why nanoplatelets exhibit a uniform thickness of eight monolayers. We synthesized a series of wurtzite nanoplatelets (ZnSe, ZnS, ZnTe, and CdSe) with an atomically uniform thickness of eight monolayers. As a representative example, the growth mechanism of 1.39 nm thick (eight monolayers) wurtzite ZnSe nanoplatelets was studied to substantiate the proposed growth kinetics. The results show that the growth of the seventh and eighth layers along the [112̅ 0] direction of 0.99 nm (six monolayers) ZnSe magic-size nanoclusters is accessible, whereas the growth of the ninth layer is unlikely to occur because the formation energy is large. This work not only gives insights into the synthesis of atomically uniform thick wurtzite semiconductor nanoplatelets but also opens up new avenues to their applications in light-emitting diodes, catalysis, detectors, and lasers.

Background: The patterns of leukemia burden have dramatically changed in recent years. This study aimed to estimate the global trends of leukemiarelated death and disability-adjusted life-years (DALYs) from 1990 to 2017. Methods: The data was acquired from the latest version of the Global Burden of Disease (GBD) study. Estimated annual percentage changes (EAPCs) were calculated to estimate the trend of age-standardized rate (ASR) of death and DALYs due to leukemia and its main subtypes from 1990 to 2017. Results: Globally, the numbers of death and DALYs due to leukemia were 347.58 × 10 3 (95% uncertainty interval [UI] = 317.26 × 10 3-364.88 × 10 3) and 11975.35 × 10 3 (95% UI = 10749.15 × 10 3-12793.58 × 10 3) in 2017, with a 31.22% and 0.03% increase in absolute numbers from 1990 to 2017, respectively. Both of their ASR showed decreasing trends from 1990 to 2017 with the EAPCs being −1.04 (95% confidence interval [CI] = (−1.10-−0.99) and −1.52 (95% CI = −1.59-−1.44), respectively. Globally, the most pronounced decreasing trend of death and DALYs occurred in chronic myeloid leukemia with EAPCs of −2.76 (95% CI = −2.88-−2.64) and −2.84 (95% CI = −2.97-−2.70), respectively, while the trend increased in acute myeloid leukemia. The death and DALYs of leukemia decreased in most areas and countries with high socio-demographic index (SDI) including Bahrain, Finland, and Australia.

Two new polar polyselenides Rb 4 Ge 4 Se 12 (1) and Cs 4 Ge 4 Se 12 (2) with rarely reported dimeric [Ge 2 Se 4 (μ-Se 2 )] 4− units were synthesized. They present large second-harmonic generation (SHG) intensities of 7.5 and 6.5 times that of the benchmark AgGaS 2 with type I phase-matching behavior, high laser-induced damaged thresholds, a wide transmission region and congruently melting behavior, making them excellent candidates for IR nonlinear optical (NLO) applications. The SHG functional motifs of both compounds are determined to be [Ge 2 Se 4 (μ-Se 2 )] 4− unit by time-dependent density functional theory calculation, which further reveals that charge transfers from the lone pairs of terminal Se atoms to the five σ* orbitals of five-membered ring Ge 2 Se 3 have a predominant contribution to the total SHG effect.