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Potassium-ion batteries (KIBs) have gained significant interest in recent years from the battery research community because potassium is an earth-abundant and redoxactive metal, thus having the potential to replace lithium-ion batteries for sustainable energy storage. However, the current development of KIBs is critically challenged by the lack of competitive electrode materials that can reversibly store large amounts of K + and electrolyte systems that are compatible with the electrode materials. Here, we report that cobalt monochalcogenide (CoSe) nanoparticles confined in N-doped carbon nanotubes (CoSe@NCNTs) can be used as a K + -storing electrode. The CoSe@NCNT composite exhibits a high initial Columbic efficiency (95%), decent capacity (435 mAh g −1 at 0.1 A g −1 ), and stability (282 mAh g −1 2.0 A g −1 after 500 cycles) in a 1 M KPF 6 −DME electrolyte with K as the anode over the voltage range from 0.01 to 3.0 V. A full KIB cell consisting of this anode and a Prussian blue cathode also shows excellent electrochemical performance (228 mAh g −1 at 0.5 A g −1 after 200 cycles). We show that the NCNT shell is effective not only in providing high electronic conductivity for fast charge transfer but also in accommodating the volume changes during cycling. We also provide experimental and theoretical evidence that KPF 6 in the electrolyte plays a catalytic role in promoting the formation of a polymer-like film on the CoSe surface during the initial activation process, and this amorphous film is of critical importance in preventing the dissolution of polyselenide intermediates into the electrolyte, stabilizing the Co 0 /K 2 Se interface, and realizing the reversibility of Co 0 /K 2 Se conversion.

Vertically stacked and laterally stitched heterostructures consisting of two-dimensional (2D) transition metal dichalcogenides (TMDCs) are predicted to possess novel electronic and optical properties, which offer opportunities for the development of next-generation electronic and optoelectronic devices. In the present work, we report the temperature-dependent synthesis of 2D TMDC heterostructures on Si/SiO substrates, including MoS-WS, WS-MoS-WS, MoWS-WS, and MoWS alloyed bilayer heterostructures by ambient pressure chemical vapor deposition (CVD). Raman and photoluminescence mapping studies demonstrate that the as-produced heterostructures show distinct structural and optical modulation. Our results indicate that the evolution of various 2D heterostructures originates from the competition between the adsorption and desorption of Mo atoms and the diffusion of W atoms under various growth temperatures. This work sheds light on the design and fabrication of heterostructures using controllable interfaces and junctions of diverse TMDC atomic layers.

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Onnia includes white rotting polypores with annual basidiocarps, a duplex context, monomitic hyphal structure, hymenial setae, and hyaline, thin-walled, smooth basidiospores. Specimens of Onnia, originating mainly from East Asia, Europe, and North America, were studied using both morphology and phylogenetic analyses. Our concatenated data set was derived from 25 collections and included (i) 25 nuc rDNA internal transcribed spacer region sequences (ITS1-5.8S-ITS2 = ITS), 17 generated in this study; and (ii) 14 nuc rDNA 28S rDNA sequences, including the D1-D2 domains, 11 of them generated in this study. The resulting maximum likelihood and Bayesian phylogenies recovered all sampled collections of Onnia as a well-supported clade. In this clade, three previously accepted species, viz., Onnia leporina, O. tomentosa, and O. triquetra, received strong support, whereas three additional lineages with strong support represent the new species described in this paper, O. subtriquetra, O. microspora, and O. tibetica. Of the six Onnia species occurring on gymnosperms, O. tomentosa and O. leporina grow mainly on Picea and have circumboreal distribution in the Northern Hemisphere. In contrast, other species that mostly grow on Pinus are geographically restricted to limited regions, viz., O. triquetra in Europe, O. subtriquetra in North America, and O. microspora and O. tibetica in Asia.

Rigidoporus and its morphologically similar genera Physisporinus, Oxyporus, and Leucophellinus, which include some forest pathogens and medicinal species, are very important groups of wood-decaying fungi. Species of these genera have not only ecological functions, but also economic importance. Phylogenetic and taxonomic studies on taxa in these genera were carried out. Inferred from phylogenies based on DNA sequences of the nuc rDNA ITS1-5.8S-ITS2 (internal transcribed spacer [ITS]) and D1-D2 domains of nuc 28S rDNA, 36 species sampled that traditionally belong to Physisporinus, Rigidoporus, Leucophellinus, and Oxyporus are nested mostly in eight lineages. Of these lineages, five (including four genera of Physisporinus, Emmia, Flaviporus, and Flavodon and one taxon "R. hypobrunneus") belong to Polyporales and three (including the genera Rigidoporus, Bridgeoporus, and Leucophellinus) belong to Hymenochaetales. Rigidoporus and Oxyporus are merged because the type species of both genera are nested in a single lineage within Hymenochaetales. Some taxon previously placed in Ceriporia and Oxyporus are transferred to Emmia and Flavodon, respectively, on the basis of current phylogeny. Utilizing a combination of the morphological and phylogenetic evidence, 16 new combinations in Bridgeoporus, Emmia, Flaviporus, Flavodon, Rigidoporus, and Physisporinus are proposed. Five new species, Physisporinus crataegi, P. lavendulus, P. subcrocatus, P. tibeticus, and Rigidoporus submicroporus, are recognized from China. Illustrated descriptions of these novel species are provided. Three taxa are treated at the generic level of Physisporinus because of limited samples.

The micro−nanofibers prepared by the electrospinning technique can be used as a good container for loading healing agents. The core−shell electrospun nanofibers with polyacrylonitrile as the outer shell and tannic acid (TA) and tung oil as the core healing agents were synthesized by a coaxial electrospinning method and exhibited pH-sensitive ability. The nanofibers as additives were added to an epoxy resin coating as a self-healing coating. The morphological stability of the electrospun nanofibers were observed by a scanning electron microscope and a transmission electron microscope. Fourier transform infrared spectroscopy and fluorescence microscopy reveal that the successful synthesis and uniform distribution of core−shell fibers. The mechanical properties test revealed that the tensile properties of the coating could be improved by adding nanofibers. The infrared mapping test, energydispersive spectrometry, and X-ray photoelectron spectroscopy, which were carried out on the scratched part of the coating, proved the release of the healing agent in the damaged part. TA forms a protective film on the exposed metal surface through molecular adsorption under acidic conditions. Meanwhile, the curing of tung oil can effectively compensate into the microcracks to form a TA protective film, which could improve the self-healing performance. As the tung oil dries and solidifies in the alkaline solution, the cross-linking effect of the molecules is combined to form a tight film and strength the self-healing ability. TA as an acidic healing agent and tung oil as an alkaline healing agent played the role of pH-sensitive products in healing the cracked coating. The selfhealing rates of coating immersing in 3.5 wt % acidic NaCl solution and alkaline solution were 81.6 and 71.2%, respectively. The composite coating shows a great pH-sensitive self-healing ability to heal the cracked coating.