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To improve the complexity and low catalytic performance and reduce the high cost of the traditional electrode preparation process for the sodium borohydride electro-oxidation reaction (BOR), in this work, a self-supported and efficient electrode material grown on nickel foam (CoNi/Co3O4/NF) was successfully designed using a simple hydrothermal synthesis method accompanied by the electrodeposition process. Benefiting from the three-dimensional nanoarray structure of CoNi/Co3O4/NF and the uniform distribution of Co and Ni modulating active sites by electrodeposition, the catalytic activity towards NaBH4 exhibits high efficiency. CoNi/Co3O4 exhibits excellent catalytic performance (up to 2157 mA cm−2 in 2 mol L−1 NaOH and 0.3 mol L−1 NaBH4), a high electrochemically active surface area (62.5 cm−2), and a low activation energy (15.56 kJ mol−1). The CoNi/Co3O4/NF electrode was further investigated on a direct sodium borohydride–hydrogen peroxide fuel cell (DBHPFC), which exhibited a maximum power density of 108.5 mW cm−2 and excellent stability. The excellent performance is mainly due to its unique nanoarray structure and electrodeposition distribution of Co and Ni active sites, which increases the electrochemical surface area and enhances the contact between the electrode and the electrolyte. [ABSTRACT FROM AUTHOR]

The exploration of bifunctional catalysts with high activity and durability is important for the electrolysis of urea–assisted hydrogen production. Therefore, we rationally designed a NiCoP catalyst with a bimetallic synergistic effect to realize the strategy of promoting the bifunctional activity of hydrogen evolution reaction (HER) and urea oxidation reaction (UOR) at high current density. Corresponding X-ray diffractogram (XRD) and X-ray photoelectron spectroscopy (XPS) analyses prove the chemical composition and successful synthesis of the NiCoP. Electrochemical activity tests indicate that the NiCoP requires a potential of 1.27 V to achieve 10 mA cm−2, and shows good UOR activity. In the overall urea electrolysis (UOR || HER), NiCoP can maintain the high current density of 200 mA cm−2 for 142 h at 1.67 V. The NiCoP exhibits excellent bifunctional catalytic activity and durability. NiCoP as bifunctional catalyst for efficient electrolysis of urea-assisted hydrogen production at high current density. [Display omitted] • NiCoP bifunctional catalyst expose more catalytically active sites. • NiCoP accelerates catalytic activity through bimetallic synergistic effect. • NiCoP can maintain the high current density (200 mA cm−2) for 142 h at 1.67 V. [ABSTRACT FROM AUTHOR]

Cobalt–based catalysts are regarded as the most innovative catalyst in the urea oxidation reaction (UOR). Nevertheless, the activity limitation of Co–based catalysts by the unavoidable self–oxidation reaction of Co species (CSOR) during UOR is generally ignored. Therefore, the interface strategy was used to synthesize a CoSe 2 hollow cube (HC)/CoSe 2 nanosheet (NS) homogeneous interface catalyst to achieve bifunctional UOR and HER performance. In situ EIS, ex situ Raman spectroscopy, and ex situ XPS analysis verify the unique mechanism of the CoSe 2 HC/CoSe 2 NS interface in triggering UOR. Electrochemical activity tests demonstrated that CoSe 2 HC/CoSe 2 NS requires only 1.27 and 1.32 V of cell voltage to reach 10 mA cm–2 in the overall urea electrolyzer (UOR || HER) and overall human urine electrolyzer (HUOR || HER) regimes, respectively. Moreover, under an industrial–grade current (500 mA cm–2), the cell voltage can be maintained at ＜2 V for 110 h. Ultraviolet (UV) spectroscopy confirms the potential of CoSe 2 HC/CoSe 2 NS to degrade urea wastewater. Software simulations reveal the advantages of the unique interface strategy of CoSe 2 HC/CoSe 2 NS in the UOR process. [Display omitted] • Construction of CoSe2 HC/CoSe2 NS interface catalyst by an interface chemistry strategy to avoid the effect of Co species self–oxidation reaction (CSOR) on UOR. • CoSe2 HC/CoSe2 NS maintained cell voltage <2 V at industrial grade current (500 mA cm-2) for 110 h in both the overall urea electrolyzer (UOR || HER) and the overall human urine electrolyzer (HUOR || HER). • Ultraviolet (UV) spectroscopy confirms the potential of CoSe2 HC/CoSe2 NS to degrade urea wastewater. • In-situ, ex situ test, and software simulations reveal the advantages of the unique interface strategy of CoSe2 HC/CoSe2 NS in the UOR process. [ABSTRACT FROM AUTHOR]

The rational design of efficient electrocatalysts for hydrogen peroxide electroreduction is essential to improve the performance of direct hydrogen peroxide fuel cells. In this study, we synthesized a Co 4 N/CoNC with a heterogeneous interface grown directly on nickel foam (NF) substrates as a highly active electrocatalyst for hydrogen peroxide (H 2 O 2) electroreduction (HPRR). Benefiting from the integrated three-dimensional structure with sufficient active sites, the high electrical conductivity, and the synergistic effect of the heterogeneous interfaces of Co 4 N and Co–N–C, the electrode provides superior H 2 O 2 electrocatalytic properties, with a current density up to 0.65 A cm−2 at −0.8 V vs. Ag/AgCl, Tafel slope at 34.86 mV dec−1 and low activation energy as 9.65 kJ mol−1 in alkaline medium. Our findings provide insights into the design of efficient H 2 O 2 electrocatalyst design. [Display omitted] • Co 4 N/CoNC heterointerface catalysts synthesized by simple hydrothermal and co-precipitation methods. • The unique structure of Co 4 N/CoNC provides a large exposure of the heterogeneous interface to the reaction environment. • Co 4 N/CoNC exhibit excellent catalytic activity and stability in the electroreduction of hydrogen peroxide. [ABSTRACT FROM AUTHOR]

A novel polyoxometalate-based metal–organic framework templated by twin-Dawson clusters, [{Cu3(μ3-O)}2(trz)6Cu2(H2O)13][H1.73P2As1.73W16.27O62]·8.25H2O (1) (trz = 1,2,4-triazole), has been synthesized under hydrothermal conditions. In 1, there are two crystal distinct motifs: a 3D metal–organic nanotube framework and seven-connected Dawson clusters. It is worth mentioning that the 3D framework possesses nanotube-like channels. The twin-H1.73P2As1.73W16.27O62 clusters (abbreviated as P2(As/W)18 clusters) as templates occupy channels of the nanotube framework. To the best of our knowledge, this represents the first metal–organic nanotube framework templated by twin-Dawson clusters. The electrochemical experiments indicate that the 1-based glassy carbon electrode (1-GCE) possesses high catalytic efficiency and high stability toward reduction of inorganic bromate molecules and oxidation of the biological molecule ascorbic acid. The electrocatalytic efficiency towards the reduction of bromate in 1 M H2SO4 solution and oxidation of AA in N2 purged solution is ca. 848.4% and 896.8% (catalytic substrate: 0.5 mM), respectively. The current signal after 100 cycles exhibits almost no loss for 1-GCE. [ABSTRACT FROM AUTHOR]

The synergy between iron doping and (1 1 1) facet engineering in Fe-NiSe octahedron reinforces catalytic activity for IRR to yield impressive photovoltaic performance of DSSCs. [Display omitted] • The possibility of Fe-NiSe (1 1 1) as CE catalysts was investigated by DFT calculation. • The well-defined Fe-doped NiSe octahedron with (1 1 1) plane was synthesized. • Synergy between doping and facet engineering reinforces electrochemical behavior. • PCE can be further enhanced by introducing Fe heteroatom into NiSe (1 1 1). Reasonable design of cost-effective counter electrode (CE) catalysts for triiodide (I 3 −) reduction reaction (IRR) by simultaneously combining heteroatom doping and facet engineering is highly desired in iodine-based dye-sensitized solar cells (DSSCs), but really challenging. Herein, the density function theory (DFT) calculations were first conducted to demonstrate that the Fe-doped NiSe (1 1 1) showed an appropriate adsorption energy for I 3 −, increased number of metal active sites, reinforced charge-transfer ability, and strong interaction between 3 d states of metal sites and 5 p state of I 1 atoms in I 3 −, compared to NiSe (1 1 1). Based on this finding, the well-defined Fe-NiSe octahedron with exposed (1 1 1) plane (marked as Fe-NiSe (1 1 1)) and NiSe octahedron with the same exposed plane (named as NiSe (1 1 1)) are controllably synthesized. When the as-prepared Fe-NiSe (1 1 1) and NiSe (1 1 1) worked as CE catalysts, Fe-NiSe (1 1 1) exhibits improved electrochemical performance with higher power conversion efficiency (PCE) than NiSe (1 1 1), providing new opportunity to replace precious Pt for DSSCs. [ABSTRACT FROM AUTHOR]

The classification of loricate peritrich ciliates is difficult because of an accumulation of several taxonomic problems. In the present work, three poorly described vaginicolids, Pyxicola pusilla , Cothurnia ceramicola and Vaginicola tincta , were isolated from the surface of two freshwater/marine algae in China. In our study, the ciliature of Pyxicola and Vaginicola is revealed for the first time, demonstrating the taxonomic value of infundibular polykineties. The small subunit rDNA , ITS1-5.8S rDNA-ITS2 region and large subunit rDNA of the above species were sequenced for the first time. Phylogenetic analyses based on these genes indicated that Pyxicola and Cothurnia are closely related. The present study suggested that the loricate species probably represent a distinct lineage in peritrich evolution and both genera Cothurnia and Thuricola are monophyletic. Pyxicola pusilla , Cothurnia ceramicola and Vaginicola tincta are recircumscribed. [ABSTRACT FROM AUTHOR]

Two new polyoxometalate-based coordination polymers have been synthesized at different pHs under identical hydrothermal conditions, (Hbib)[Cu2(bib)2(PMo12O40)] (1) and (Hbib)2[Cu(bib) (PMo12O40)]·2H2O (2) (bib = 4-bis(imidazol-1-yl) benzene). Their structures were determined by single crystal X-ray diffraction analyses and characterized by routine methods. When the pH was adjusted to 2.0 − 2.5, 1 was obtained, which exhibits a 1-D rail-like chain. Compound 2 was obtained at pH of 2.5 − 3.2 and exhibits a 2-D layer with (44) sql net. The pH of the reaction plays a key role in the assembly of the polyoxometalate-based coordination polymer. The electrochemical experiments indicate that 2-based carbon paste electrode possesses high catalytic efficiency and high stability towards reduction of iodate and oxidation of ascorbic acid. [ABSTRACT FROM AUTHOR]

• Two new 2D POMOFs were synthesized by a simple hydrothermal synthesis method. • POMOFs were obtained by modulating the single active site (SAS) for the first time. • The single active site (SAS) in polymolybdate enhanced electrochemical performance. The multi-electron redox properties of polyoxometalates (POMs) and the high surface area and diverse structures of metal-organic frameworks (MOFs) have led to the attracted much attention of polyoxometalate-based metal-organic frameworks (POMOFs) as supercapacitor electrode materials. To investigate the relationship between the structure and catalytic performance of POMOF electrode materials, two novel 2D POMOF crystalline materials were synthesized by a one-step hydrothermal method, namely (H 2 bipy)[CuI 2 (bipy) 2 (H 3 PMo 11 CuO 40)] (1) and H[CuI 2 (bipy) 2 CuI(bipy)(β-Mo 8 O 26 ] (2) (bipy = 4,4′-bipyridine). Compound 1 shows a Cu-substituted Keggin-based 2D POMOF layer, and compound 2 shows a novel 2D + 1D hydrotalcite-like architecture. Compound 1 exhibits better electrochemical performance, and the prepared electrode material has a specific capacitance of 407.7 F g−1 at 3 A g−1 and maintains cycling stability of 89.5% of the initial capacitance after 1000 cycles at a current density of 10 A g−1. The compounds 1 – 2 have the potential in optimizing electrode materials for POMOF-based capacitors applications. The new 2D POMOF was synthesized by replacing single active site (SAS) Keggin polymolybdate with transition metal copper for the first time, which significantly contribute to improve electrochemical capacitor performance. [Display omitted] [ABSTRACT FROM AUTHOR]

The peritrichous genus Ophrydium is relatively distinctive since its colonies have a gelatinous lorica. In the present work, one morphologically well‐described species, Ophrydium crassicaule, was collected from a freshwater habitat in China. Both morphological characters and sequence data for SSU rDNA, ITS1‐5.8S‐ITS2 region and LSU rDNA were obtained. Morphologically, O. crassicaule is characterized by its elongated vase‐shaped zooid, single‐layered peristomial lip, dichotomously branched stalk, colony with gelatinous lorica, and infundibular polykinety 3 (P3) containing one short inner row and two long outer rows. Phylogenetic analyses revealed that the genus Ophrydium is monophyletic and nests within the family Vorticellidae. In addition, we briefly revise the nominal congeners for aiding the species identification in future studies. [ABSTRACT FROM AUTHOR]

A novel polyoxometalate-encapsulating polycatenated metal-organic framework, (bib) 0.5 [Cu 2 (bib) 3.5 (GeW 12 O 40)]·H 2 O (1) (bib = 1,4-bis(1-imidazol-yl)-2,5-dimethyl benzene), has been synthesized under hydrothermal conditions. In compound 1 , 1D molecular ladders and 2D square grid layers is further catenated to the two adjacent such motifs in inclined fashion to give an 1D+2D → 3D polycatenaned metal-organic framework with nanotube channels, in which nanosized Keggin anions as guests are encapsulated for the first time. Compound 1 represents a first case of Keggin-type polyoxometalate-encapsulating 1D+2D→3D polycatenated metal-organic framework. The electrochemical studies show that modified electrode of 1 exhibits highly efficient electrocatalytic activity toward reduction of inorganic molecule bromate (BrO 3 -). The electrocatalytic reaction mechanism of 1 -GCE toward reduction of BrO 3 - has been illuminated. The photoluminescence property of 1 was also investigated. A novel polyoxometalate-encapsulating 1D+2D→3D polycatenated metal-organic framework has been synthesized. The modified electrode of compound 1 exhibits highly efficient electrocatalytic activity toward reduction of bromate (BrO 3 -). Image 1 • A novel polyoxometalate-encapsulating polycatenated metal-organic framework is synthesized and structurally characterized. • Compound 1 represents a first case of Keggin-type polyoxometalate-encapsulating 1D+2D.→3D polycatenated metal-organic framework. • The modified electrode of compound 1 exhibits highly efficient electrocatalytic activity toward reduction of bromate. [ABSTRACT FROM AUTHOR]

Ampullofolliculina Hadži, 1951 is a monotypic genus, the only species being A. lageniformis which was first discovered in estuarine habitats in the U.S. and has never been redescribed. In the present study, we investigated the taxonomy and phylogeny of A. lageniformis Hadži, 1951 based on analyses of a population collected from a brackish wetland in Ningbo, China. The main characteristics of this species are as follows: trophont about 450–700 μm long in vivo with two short, rounded peristomial lobes of equal size; lorica flask‐shaped, transparent and smooth with a short, wide neck at the base of which two transparent valves are asymmetrically inserted; cortex with brownish to reddish cortical granules and greenish pigment granules; about 80 somatic kineties evenly arranged; moniliform macronucleus with 4–8 ellipsoidal nodules; swarmer dark green, vermiform in shape, about 200–350 μm long in vivo, with about 60 adoral membranelles and 85 somatic kineties, no mouth nor paroral membrane. Phylogenetic analyses inferred from SSU rDNA sequences show that A. lageniformis is closely related to Folliculina and Eufolliculina which nest within a large clade that comprises five families, i.e. Stentoridae, Blepharismidae, Fabreidae, Maristentoridae, and Folliculinidae. [ABSTRACT FROM AUTHOR]

A new polyoxovanadate-based metal–organic framework, [Cu(Pz)](V4O10) (1) (Pz = Pyrazine) has been synthesized under hydrothermal conditions. Single crystal X-ray diffraction analysis reveals that compound 1 displays a 3D framework with a rare reduced V4O102− layer. The electrochemical study shows that 1 exhibits bifunctional electrocatalytic activities toward reduction of iodate and oxidation of ascorbic acid. Surface photovoltage spectroscopy (SPS) and electric field induced surface photovoltage spectroscopy (EFISPS) measurements reveal that 1 has the behavior of an n-type semiconductor. In addition, 1 shows excellent photocatalytic activity for the decomposition of Rhodamine-B dye under visible light. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phylogenomic analysis was performed based on 85 taxa and 157 nuclear genes. • Urocentrids represent a new subclass Urocentria n. subcl. within Oligohymenophorea. • Paranassula is supported as an order in the subclass Peniculia. • Peritrichia is the earliest diverging clade within Oligohymenophorea. • Differed from other oligohymenophoreans, peritrichs reassign UAR to glutamate. The class Oligohymenophorea is one of the most diverse assemblage of ciliated protists, which are particularly important in fundamental biological studies including understanding the evolutionary relationships among the lineages. Phylogenetic relationships within the class remain largely elusive, especially within the subclass Peniculia, which contains the long-standing problematic taxa Urocentrum and Paranassula. In the present study, we sequenced the genomes and/or transcriptomes of six non-culturable oligohymenophoreans using single-cell sequencing techniques. Phylogenomic analysis was performed based on expanded taxon sampling of 85 taxa, including 157 nuclear genes encoding 36,953 amino acids. The results indicate that: (1) urocentrids form an independent branch that is sister to the clade formed by Scuticociliatia and Hymenostomatia, which, together with the morphological data, supports the establishment of a new subclass, Urocentria n. subcl., within Oligohymenophorea; (2) phylogenomic analysis and ortholog comparison reveal a close relationship between Paranassula and peniculines, providing corroborative evidence for removing Paranassula from Nassulida and elevating it as an order, Paranassulida, within the subclass Peniculia; (3) based on the phylogenomic analyses and morphological data, we hypothesize that Peritrichia is the earliest diverging clade within Oligohymenophorea while Scuticociliatia and Hymenostomatia share the most common ancestor, followed successively by Urocentria and Peniculia. In addition, stop codon analyses indicate that oligohymenophoreans widely use UGA as the stop codon, while UAR are reassigned to glutamate (peritrichs) or glutamine (others), supporting the evolutionary hypothesis. [ABSTRACT FROM AUTHOR]

During an investigation of parasitic ciliates in northern China, two Trichodina species, T. acuta Lom, 1970 and T. nigra Lom, 1960, were isolated from the freshwater fish Cyprinus carpio Linnaeus, 1758. The morphology of each species was investigated based on dry silver nitrate-stained specimens. In addition, the molecular phylogeny of each was analyzed based on small subunit ribosomal DNA (SSU rDNA) sequence data. Trichodina acuta can be distinguished from its congeners by the undefined periphery of the central circle, the distinct gap between the rays and the central circle, and the distinctly sickle-shaped blades. Trichodina nigra is a cosmopolitan ciliate and is characterized by its densely linked denticles, broad, rounded spatula-shaped blades, robust central parts, and well developed rays. Phylogenetic analyses revealed that T. acuta and T. nigra nest within different clades, supporting the assertion that the GC content of SSU rDNA sequences could reflect evolutionary relationships among Trichodina species. [Display omitted] [ABSTRACT FROM AUTHOR]