Hydrothermal exfoliated molybdenum disulfide nanosheets as anode material for lithium ion batteries

Ultrathin MoS2 nanosheets were prepared in high yield using a facile and effective hydrothermal intercalation and exfoliation route. The products were characterized in detail using X-ray diffraction, scanning electron microscopy, transmission electron microscopy and Raman spectroscopy. The results show that the high yield of MoS2 nanosheets with good quality was successfully achieved and the dimensions of the immense nanosheets reached 1 μm-2/zm. As anode material for Li-ion batteries, the as-prepared MoS2 nanosheets electrodes exhibited a good initial capacity of 1190 mAh.g-l and excellent cyclic stability at constant current density of 50 mA.g-1. After 50 cycles, it still delivered reversibly sustained high capacities of 750 mAh.g-1.

Carbon matrix/SiNWs heterogeneous block as improved reversible anodes material for lithium ion batteries

A novel carbon matrix/silicon nanowires(SiNWs) heterogeneous block was successfully produced by dispersing SiNWs into templated carbon matrix via a modified evaporation induced self-assembly method. The heterogeneous block was determined by X-ray diffraction, Raman spectra and scanning electron microscopy. As an anode material for lithium batteries, the block was investigated by cyclic voltammograms(CV), charge/discharge tests, galvanostatic cycling performance and A. C. impedance spectroscopy. We show that the SiNWs disperse into the framework, and are nicely wrapped by the carbon matrix. The heterogeneous block exhibits superior electrochemical reversibility with a high specific capacity of 529.3 mAh/g in comparison with bare SiNWs anode with merely about 52.6 mAh/g capacity retention. The block presents excellent cycle stability and capacity retention which can be attributed to the improvement of conductivity by the existence of carbon matrix and the enhancement of ability to relieve the large volume expansion of SiNWs during the lithium insertion/extraction cycle. The results indicate that the as-prepared carbon matrix/SiNWs heterogeneous block can be an attractive and potential anode material for lithium-ion battery applications.

Genomic diversity and ecological distribution of marine Pseudoalteromonas phages

Pseudoalteromonas,with a ubiquitous distribution,is one of the most abundant marine bacterial genera.It is especially abundant in the deep sea and polar seas,where it has been found to have a broad metabolic capacity and unique co-existence strategies with other organisms.However,only a few Pseudoalteromonas phages have so far been isolated and investigated and their genomic diversity and distribution patterns are still unclear.Here,the genomes,taxonomic features and distribution patterns of Pseudoalteromonas phages are systematically analyzed,based on the microbial and viral genomes and metagenome datasets.A total of 143 complete or nearly complete Pseudoalteromonas-associated phage genomes(PSAPGs)were identifed,including 34 Pseudoalteromonas phage isolates,24 proviruses,and 85 Pseudoalteromonas-associated uncultured viral genomes(UViGs);these were assigned to 47 viral clusters at the genus level.Many integrated proviruses(n=24)and flamentous phages were detected(n=32),suggesting the prevalence of viral lysogenic life cycle in Pseudoalteromonas.PSAPGs encoded 66 types of 249 potential auxiliary metabolic genes(AMGs)relating to peptidases and nucleotide metabolism.They may also participate in marine biogeochemical cycles through the manipulation of the metabolism of their hosts,especially in the phosphorus and sulfur cycles.Siphoviral and flamentous PSAPGs were the predominant viral lineages found in polar areas,while some myoviral and siphoviral PSAPGs encoding transposase were more abundant in the deep sea.This study has expanded our understanding of the taxonomy,phylogenetic and ecological scope of marine Pseudoalteromonas phages and deepens our knowledge of viral impacts on Pseudoalteromonas.It will provide a baseline for the study of interactions between phages and Pseudoalteromonas in the ocean.

Correction: Genomic diversity and ecological distribution of marine Pseudoalteromonas phages

In this article the graphics relating to Figs.2 and 3 captions had been interchanged;the fgure(s)should have appeared as shown below.The original article has been corrected.Open Access This article is licensed under a Creative Commons Attribution 4.0 International License,which permits use,sharing.