We report on the synthesis of inorganic fullerene-like molybdenum disulfide (MoS(2)) nanoparticles by pulsed laser ablation (PLA) in water. The final products were characterized by scanning electron microscopy, X-ray diffraction, transmission electron microscopy, and resonance Raman spectroscopy, etc. Cell viability studies show that the as-prepared MoS(2) nanoparticles have good solubility and biocompatibility, which may show a great potential in various biomedical applications. It is shown that the technique of PLA in water also provides a green and convenient method to synthesize novel nanomaterials, especially for biocompatible nanomaterials.

A unique sandwiched structure of TiOx/Au‐NPs/TiOx is used to improve the charge transport properties of a TiOx film via plasmonic‐mediated hot carrier injection at the metal‐semiconductor Schottky junction. The injected carrier helps to fill trap states and to further decrease the Fermi level of TiOx. The combined effects dramatically enhance the perovskite solar cell performance, with a power conversion efficiency of 16.2%.

Seed microbiome includes special endophytic or epiphytic microbial taxa associated with seeds, which affects seed germination, plant growth, and health. Here, we analyzed the core microbiome of 21 Salvia miltiorrhiza seeds from seven different geographic origins using 16S rDNA and ITS amplicon sequencing, followed by bioinformatics analysis. The whole bacterial microbiome was classified into 17 microbial phyla and 39 classes. Gammaproteobacteria (67.6%), Alphaproteobacteria (15.6%), Betaproteobacteria (2.6%), Sphingobacteria (5.0%), Bacilli (4.6%), and Actinobacteria (2.9%) belonged to the core bacterial microbiome. Dothideomycetes comprised 94% of core fungal microbiome in S. miltiorrhiza seeds, and another two dominant classes were Leotiomycetes (3.0%) and Tremellomycetes (2.0%). We found that terpenoid backbone biosynthesis, degradation of limonene, pinene, and geraniol, and prenyltransferases, were overrepresented in the core bacterial microbiome using phylogenetic examination of communities by reconstruction of unobserved states (PICRUSt) software. We also found that the bacterial genera Pantoea, Pseudomonas, and Sphingomonas were enriched core taxa and overlapped among S. miltiorrhiza, maize, bean, and rice, while a fungal genus, Alternaria, was shared within S. miltiorrhiza, bean, and Brassicaceae families. These findings highlight that seed-associated microbiomeis an important component of plant microbiomes, which may be a gene reservoir for secondary metabolism in medicinal plants.

In this work, we demonstrate high-efficiency planar perovskite solar cells (PSCs), using room-temperature sputtered niobium oxide (NbO) as the electron-transporting layer (ETL). Widely spread ETL-like TiO often requires high-temperature (>450 °C) sintering, which is not desired for the fabrication of flexible devices. The amorphous NbO (labeled as a-NbO) ETL, without any heat treatment, can give a best power conversion efficiency (PCE) of 17.1% for planar PSCs. Interestingly, the crystalline NbO (labeled as c-NbO), with high-temperature (500 °C) annealing, results in a very similar PCE of 17.2%, indicating the great advantage of a-NbO in energy saving. We thus carried out a systematical investigation on the properties of the a-NbO film. The Hall effect measurements indicate both high mobility and conductivity of the a-NbO film. Kelvin probe force microscopy measurements define the Fermi levels of a-NbO and c-NbO as -4.31 and -4.02 eV, respectively, which allow efficient electron extraction at the NbO/perovskite interface, regardless of the additional heat treatment on NbO film. Benefitting from the low-temperature process, we further demonstrated flexible PSCs based on a-NbO, with a considerable PCE of 12.1%. The room-temperature processing and relatively high device performance of a-NbO suggest a great potential for its application in optoelectrical devices.

An all-solution-processed quantum dots (QDs) light emitting diode (QLED) consists of different layers deposited from various orthogonal solvents. Here, the authors develop a general solvent selection strategy to obtain orthogonal solubility properties as well as high film quality. It is found that a "poor" QDs film morphology with striation defects often occurs when the QDs film is deposited from "bad" solvent. A physical model is presented to rationalize the observed striation defects, and then a general solvent selection strategy is proposed to prevent both surface striation defects and the dissolving of the underlying layers by carefully choosing the "good" solvent for QDs. A compact QDs film can be fabricated without altering the original morphology of underlying functional layers in a QLED device, leading to significant device performance improvement. An external quantum efficiency of 15.45% is achieved in a green QLED with uniform emitting region. This solvent selection strategy provides a general way to deposit high quality films for most of the solution-processed multilayer optoelectronic devices.