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Showing papers by "Henan Normal University published in 2019"


Journal ArticleDOI
TL;DR: The new version of Evolview was designed to provide simple tree uploads, manipulation and viewing options with additional annotation types, and the ‘dataset system’ used for visualizing tree information has evolved substantially from the previous version.
Abstract: Evolview is an interactive tree visualization tool designed to help researchers in visualizing phylogenetic trees and in annotating these with additional information. It offers the user with a platform to upload trees in most common tree formats, such as Newick/Phylip, Nexus, Nhx and PhyloXML, and provides a range of visualization options, using fifteen types of custom annotation datasets. The new version of Evolview was designed to provide simple tree uploads, manipulation and viewing options with additional annotation types. The 'dataset system' used for visualizing tree information has evolved substantially from the previous version, and the user can draw on a wide range of additional example visualizations. Developments since the last public release include a complete redesign of the user interface, new annotation dataset types, additional tree visualization styles, full-text search of the documentation, and some backend updates. The project management aspect of Evolview was also updated, with a unified approach to tree and project management and sharing. Evolview is freely available at: https://www.evolgenius.info/evolview/.

436 citations


Journal ArticleDOI
TL;DR: This work highlights the synergy from heterointerfaces in oxygen electrocatalysis, thus providing a promising approach for advanced metal-air cathode materials.
Abstract: Rational design and synthesis of highly active and robust bifunctional non-noble electrocatalysts for both oxygen evolution reaction (OER) and oxygen reduction reaction (ORR) are urgently required for efficient rechargeable metal-air batteries. Herein, abundant MnO/Co heterointerfaces are engineered in porous graphitic carbon (MnO/Co/PGC) polyhedrons via a facile hydrothermal-calcination route with a bimetal-organic framework as the precursor. The in situ generated Co nanocrystals not only create well-defined heterointerfaces with high conductivity to overcome the poor OER activity but also promote the formation of robust graphitic carbon. Owing to the desired composition and formation of the heterostructures, the resulting MnO/Co/PGC exhibits superior activity and stability toward both OER and ORR, which makes it an efficient air cathode for the rechargeable Zn-air battery. Importantly, the homemade Zn-air battery is able to deliver excellent performance including a peak power density of 172 mW cm-2 and a specific capacity of 872 mAh g-1 , as well as excellent cycling stability (350 cycles), outperforming commercial mixed Pt/C||RuO2 catalysts. This work highlights the synergy from heterointerfaces in oxygen electrocatalysis, thus providing a promising approach for advanced metal-air cathode materials.

377 citations


Journal ArticleDOI
27 Sep 2019-Science
TL;DR: The temperature-dependent interplay of three separate electronic bands in hole-doped tin sulfide (SnS) crystals leads to synergistic optimization between effective mass and carrier mobility and can be boosted through introducing selenium (Se), enhancing the power factor and lowering the thermal conductivity after Se alloying.
Abstract: Thermoelectric technology allows conversion between heat and electricity. Many good thermoelectric materials contain rare or toxic elements, so developing low-cost and high-performance thermoelectric materials is warranted. Here, we report the temperature-dependent interplay of three separate electronic bands in hole-doped tin sulfide (SnS) crystals. This behavior leads to synergistic optimization between effective mass (m*) and carrier mobility (μ) and can be boosted through introducing selenium (Se). This enhanced the power factor from ~30 to ~53 microwatts per centimeter per square kelvin (μW cm−1 K−2 at 300 K), while lowering the thermal conductivity after Se alloying. As a result, we obtained a maximum figure of merit ZT (ZTmax) of ~1.6 at 873 K and an average ZT (ZTave) of ~1.25 at 300 to 873 K in SnS0.91Se0.09 crystals. Our strategy for band manipulation offers a different route for optimizing thermoelectric performance. The high-performance SnS crystals represent an important step toward low-cost, Earth-abundant, and environmentally friendly thermoelectrics.

356 citations


Journal ArticleDOI
30 Jul 2019-ACS Nano
TL;DR: A highly polarization-sensitive, broadband, self-powered photodetector based on graphene/PdSe2/germanium heterojunction with an ultrahigh polarization sensitivity of 112.2 is achieved, which represents the best result for 2D layered material-based photodtectors.
Abstract: Polarization-sensitive photodetection in a broad spectrum range is highly desired due to the great significance in military and civilian applications. Palladium diselenide (PdSe2), a newly explored air-stable, group 10 two-dimensional (2D) noble metal dichalcogenide with a puckered pentagonal structure, holds promise for polarization-sensitive photodetection. Herein, we report a highly polarization-sensitive, broadband, self-powered photodetector based on graphene/PdSe2/germanium heterojunction. Owing to the enhanced light absorption of the mixed-dimensional van der Waals heterojunction and the effective carrier collection with graphene transparent electrode, the photodetector exhibits superior device performance in terms of a large photoresponsivity, a high specific detectivity, a fast response speed to follow nanosecond pulsed light signal, and a broadband photosensitivity ranging from deep ultraviolet (DUV) to mid-infrared (MIR). Significantly, highly polarization-sensitive broadband photodetection with an ultrahigh polarization sensitivity of 112.2 is achieved, which represents the best result for 2D layered material-based photodetectors. Further, we demonstrated the high-resolution polarization imaging based on the heterojunction device. This work reveals the great potential of 2D PdSe2 for high-performance, air-stable, and polarization-sensitive broadband photodetectors.

344 citations


Journal ArticleDOI
TL;DR: By improving fundamental understanding of materials properties relevant to the rechargeable zinc and air electrodes, zinc-air batteries will be able to make a significant impact on the future energy storage for electric vehicle application.
Abstract: Over the past decade, the surging interest for higher-energy-density, cheaper, and safer battery technology has spurred tremendous research efforts in the development of improved rechargeable zinc-air batteries. Current zinc-air batteries suffer from poor energy efficiency and cycle life, owing mainly to the poor rechargeability of zinc and air electrodes. To achieve high utilization and cyclability in the zinc anode, construction of conductive porous framework through elegant optimization strategies and adaptation of alternate active material are employed. Equally, there is a need to design new and improved bifunctional oxygen catalysts with high activity and stability to increase battery energy efficiency and lifetime. Efforts to engineer catalyst materials to increase the reactivity and/or number of bifunctional active sites are effective for improving air electrode performance. Here, recent key advances in material development for rechargeable zinc-air batteries are described. By improving fundamental understanding of materials properties relevant to the rechargeable zinc and air electrodes, zinc-air batteries will be able to make a significant impact on the future energy storage for electric vehicle application. To conclude, a brief discussion on noteworthy concepts of advanced electrode and electrolyte systems that are beyond the current state-of-the-art zinc-air battery chemistry, is presented.

341 citations


Journal ArticleDOI
TL;DR: In this article, a layered B/N co-doped porous carbon (LDC) guided by the intercalator is proposed for the first time as cathode material for high-energy-power ZHSs to efficiently mitigate these issues.

307 citations


Journal ArticleDOI
TL;DR: In this paper, the authors showed that the half-unit-cell ZnIn2S4 monolayer possesses an excellent photocatalytic performance compared with the one unit-cell bilayer owing to its increased carrier lifetime.
Abstract: Two-dimensional (2D) photocatalytic materials have attracted extensive attention due to the unique properties different from those of their bulk. 2D ZnIn2S4 nanosheets with the intrinsic bilayer in one-unit-cell with interlayer force generally perform better than that of the bulk in photocatalytic hydrogen evolution. Here, we for the first time demonstrate that the half-unit-cell ZnIn2S4 monolayer possesses an excellent photocatalytic performance compared with the one-unit-cell bilayer owing to its increased carrier lifetime. Meanwhile, sulfur vacancies are introduced in the half-unit-cell ZnIn2S4 monolayer to trap the photo-generated electrons and further prolong the carrier lifetime. First-principle calculations reveal that sulfur vacancies in the ZnIn2S4 monolayer induce more charge carriers at the valence band maximum to participate in the photocatalytic activity. As expected, the photocatalytic hydrogen production rate of the monolayer ZnIn2S4 with sulfur vacancies is up to 13.478 mmol/g/h under the visible light irradiation, which is much higher than the available values reported of ZnIn2S4 so far. These findings provide a new strategy for optimization of 2D photocatalysts to enhance photocatalytic hydrogen evolution.

306 citations


Journal ArticleDOI
TL;DR: A Rubidium-Cesium alloyed, quasi-two-dimensional perovskite is reported and its great potential for pure-blue PeLED applications is demonstrated and composition engineering and in-situ passivation are conducted to further improve the material’s emission property and stabilities.
Abstract: Device performance and in particular device stability for blue perovskite light-emitting diodes (PeLEDs) remain considerable challenges for the whole community. In this manuscript, we conceive an approach by tuning the ‘A-site’ cation composition of perovskites to develop blue-emitters. We herein report a Rubidium-Cesium alloyed, quasi-two-dimensional perovskite and demonstrate its great potential for pure-blue PeLED applications. Composition engineering and in-situ passivation are conducted to further improve the material’s emission property and stabilities. Consequently, we get a prominent film photoluminescence quantum yield of around 82% under low excitation density. Encouraged by these findings, we finally achieve a spectra-stable blue PeLED with the peak external quantum efficiency of 1.35% and a half-lifetime of 14.5 min, representing the most efficient and stable pure-blue PeLEDs reported so far. The strategy is also demonstrated to be able to generate efficient perovskite blue emitters and PeLEDs in the whole blue spectral region (from 454 to 492 nm). Besides device operational stability, the color stability is also an important challenge for the perovskite light-emitting diodes, especially the blue ones. Here Jiang et al. report the most efficient and color stable pure-blue perovskite LEDs so far, with a half-lifetime of 14.5 minutes.

298 citations


Journal ArticleDOI
TL;DR: In this article, a general dual-templating approach was proposed to prepare hierarchically macro-/meso-/microporous heteroatom-doped carbon materials using diverse low-cost biomass precursors.
Abstract: Herein we report a general dual-templating approach to prepare hierarchically macro-/meso-/microporous heteroatom-doped carbon materials using diverse low-cost biomass precursors. Nitrogen/oxygen-doped carbon materials with hierarchical porosity are first synthesized as an example using Mg5(OH)2(CO3)4/ZnCl2 as hard templates and glucose/urea as carbon and heteroatom sources through a high-temperature thermal reaction and subsequent etching treatment. This approach is very versatile and can be applied to produce many hierarchically structured heteroatom-doped carbon materials via pyrolysis of other biomass precursors, including roots, stems, leaves, flowers and fruits of various plants. Lastly, we demonstrate that the as-prepared hierarchically porous nitrogen/oxygen-doped carbon materials manifest enhanced electrocatalytic performance for oxygen reduction reaction in alkaline electrolyte.

293 citations



Journal ArticleDOI
TL;DR: In this paper, a copper ferrite modified graphitic carbon nitride (CuFe2O4/g-C3N4) nanocomposite was successfully synthesized for the utilization as a visible-light responsive photocatalyst.
Abstract: A copper ferrite modified graphitic carbon nitride (CuFe2O4/g-C3N4) nanocomposite was successfully synthesized for the utilization as a visible-light responsive photocatalyst. The as-synthesized catalysts were characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV–vis diffuse reflectance spectra (UV–vis/DRS), photoluminescence (PL) analysis, and an electrochemical workstation. Compared to g-C3N4 and CuFe2O4, the CuFe2O4/g-C3N4 composites possessed excellent photocatalytic performance for the destruction of propranolol (PRO). A removal efficiency of 82.2% was achieved with 1 g/L catalyst and 1 mM peroxydisulfate (PDS) under visible light irradiation (λ −), h+, hydroxyl radicals ( OH), and sulfate radicals (SO4 −). Moreover, the byproducts of PRO were investigated by HPLC-MS/MS, and the transformation pathways under the Vis/g-C3N4/CuFe2O4/PDS process were tentatively proposed based on the intermediates. The research provided a potential approach of CuFe2O4 modified g-C3N4 as a photocatalyst combined with PDS for the treatment of contaminated water.

Journal ArticleDOI
TL;DR: In this paper, a novel phosphorus and oxygen co-doped graphitic carbon nitride (POCN) was successfully synthesized through a one-step thermal polymerization method and exhibited remarkable photocatalytic activity for the photocatalysis degradation of fluoroquinolones (FQs).

Journal ArticleDOI
TL;DR: In this paper, a battery pack with 32 high energy density cylindrical lithium-ion batteries is designed to comprehensively investigate the characteristics of an air cooling system, and a series of evaluation parameters, the air cooling performances of aligned, staggered, and cross battery packs are experimentally studied and compared at different air inlet velocities.

Journal ArticleDOI
TL;DR: The mild and highly enantioselective synthesis of 2,3'-biindolyls via underexplored integration of C-H activation and alkyne cyclization using a unified chiral Rh(III) catalyst.
Abstract: Enantiomeric access to pentatomic biaryls is challenging due to their relatively low rotational barrier. Reported herein is the mild and highly enantioselective synthesis of 2,3′-biindolyls via und...

Journal ArticleDOI
TL;DR: The results show that the proposed method can provide a better solution for imbalanced fault diagnosis on the basis of generating similar fault samples and outperforms three widely used sample synthesis techniques, such as random oversampling, synthetic minority oversamplings technique, and the principal curve-based oversampler method in terms of diagnosis accuracy and numerical stability.
Abstract: Due to the real working conditions and data acquisition equipment, the collected working data of bearings are actually limited. Meanwhile, as the rolling bearing works in the normal state at most times, it is easy to raise the imbalance problem of fault types which restricts the diagnosis accuracy and stability. To solve these problems, we present an imbalanced fault diagnosis method based on the generative adversarial network (GAN) and provide a comparative study in detail. The key idea is utilizing GAN, a kind of deep learning technique, to generate synthetic samples for minority fault class and then improve the generalization ability of the fault diagnosis model. First, this method applies fast Fourier transform to pre-process the original vibration signal and then obtains the frequency spectrum of fault samples. Second, it uses the spectrum data as the input of GAN to generate the synthetic minority samples following the data distribution of the real samples. Finally, it puts the synthetic samples into the training set and builds a stacked denoising auto encoder model for fault diagnosis. To testify the effectiveness of the proposed method, a series of comparative experiments is carried out on the CWRU bearing dataset. The results show that the proposed method can provide a better solution for imbalanced fault diagnosis on the basis of generating similar fault samples. As a comparative study, the proposed method is compared to several diagnostic methods with traditional time-frequency domain characteristics. Moreover, we also demonstrate that the proposed method outperforms three widely used sample synthesis techniques, such as random oversampling, synthetic minority oversampling technique, and the principal curve-based oversampling method in terms of diagnosis accuracy and numerical stability.

Journal ArticleDOI
TL;DR: A meta-analysis of 3,049 paired measurements from 417 peer-reviewed articles demonstrated that, through adopting CSA practices, cropland could be an improved carbon sink and highlighted the importance of considering local environmental factors in identifying appropriate CSA Practices for mitigating greenhouse gas emissions while ensuring crop productivity.
Abstract: Climate-smart agriculture (CSA) management practices (e.g., conservation tillage, cover crops, and biochar applications) have been widely adopted to enhance soil organic carbon (SOC) sequestration and to reduce greenhouse gas emissions while ensuring crop productivity. However, current measurements regarding the influences of CSA management practices on SOC sequestration diverge widely, making it difficult to derive conclusions about individual and combined CSA management effects and bringing large uncertainties in quantifying the potential of the agricultural sector to mitigate climate change. We conducted a meta-analysis of 3,049 paired measurements from 417 peer-reviewed articles to examine the effects of three common CSA management practices on SOC sequestration as well as the environmental controlling factors. We found that, on average, biochar applications represented the most effective approach for increasing SOC content (39%), followed by cover crops (6%) and conservation tillage (5%). Further analysis suggested that the effects of CSA management practices were more pronounced in areas with relatively warmer climates or lower nitrogen fertilizer inputs. Our meta-analysis demonstrated that, through adopting CSA practices, cropland could be an improved carbon sink. We also highlight the importance of considering local environmental factors (e.g., climate and soil conditions and their combination with other management practices) in identifying appropriate CSA practices for mitigating greenhouse gas emissions while ensuring crop productivity.

Journal ArticleDOI
TL;DR: The as-obtained cobalt sulfide multi-shelled nanoboxes exhibit enhanced sodium-storage properties when evaluated as anodes for sodium-ion batteries.
Abstract: We report the synthesis of cobalt sulfide multi-shelled nanoboxes through metal-organic framework (MOF)-based complex anion conversion and exchange processes. The polyvanadate ions react with cobalt-based zeolitic imidazolate framework-67 (ZIF-67) nanocubes to form ZIF-67/cobalt polyvanadate yolk-shelled particles. The as-formed yolk-shelled particles are gradually converted into cobalt divanadate multi-shelled nanoboxes by solvothermal treatment. The number of shells can be easily controlled from 2 to 5 by varying the temperature. Finally, cobalt sulfide multi-shelled nanoboxes are produced through ion-exchange with S2- ions and subsequent annealing. The as-obtained cobalt sulfide multi-shelled nanoboxes exhibit enhanced sodium-storage properties when evaluated as anodes for sodium-ion batteries. For example, a high specific capacity of 438 mAh g-1 can be retained after 100 cycles at the current density of 500 mA g-1 .

Journal ArticleDOI
TL;DR: In this article, a high activity bifunctional non-noble electrocatalysts, targeting both ORR and OER, are rationally designed by integrating the merits of both NiFe2O4 quantum dots and carbons nanotubes.

Journal ArticleDOI
TL;DR: A heuristic feature selection algorithm with low computational complexity is presented to improve the performance of cancer classification using gene expression data and outperforms other related methods in terms of the number of selected genes and the classification accuracy, especially as the size of the genes increases.

Journal ArticleDOI
TL;DR: Light is shed on using OV-rich semiconductors as a promising support to design efficient and durable nonprecious electrocatalysts to solve the problem of corrosion of rechargeable zinc-air batteries.
Abstract: The highly oxidative operating conditions of rechargeable zinc-air batteries causes significant carbon-support corrosion of bifunctional oxygen electrocatalysts. Here, a new strategy for the catalyst support design focusing on oxygen vacancy (OV)-rich, low-bandgap semiconductor is proposed. The OVs promote the electrical conductivity of the oxide support, and at the same time offer a strong metal-support interaction (SMSI), which enables the catalysts to have small metal size, high catalytic activity, and high stability. The strategy is demonstrated by successfully synthesizing ultrafine Co-metal-decorated 3D ordered macroporous titanium oxynitride (3DOM-Co@TiOx Ny ). The 3DOM-Co@TiOx Ny catalyst exhibits comparable activities for oxygen reduction and evolution reactions, but much higher cycling stability than noble metals in alkaline conditions. The zinc-air battery using this catalyst delivers an excellent stability with less than 1% energy efficiency loss over 900 charge-discharge cycles at 20 mA cm-2 . The high stability is attributed to the strong SMSI between Co and 3DOM-TiOx Ny which is verified by density functional theory calculations. This work sheds light on using OV-rich semiconductors as a promising support to design efficient and durable nonprecious electrocatalysts.

Journal ArticleDOI
TL;DR: In this paper, an effective strategy that can tailor Fe-N-C catalysts to simultaneously enrich the number of active sites while boosting their intrinsic activity and utilization is reported, achieved by edge engineering of FeN4 sites via a simple ammonium chloride salt-assisted approach.
Abstract: DOI: 10.1002/aenm.201803737 Proton exchange membrane fuel cells (PEMFCs) fueled by renewable hydrogen are attractive and promising devices to provide sustainable and clean energy.[1] However, a major drawback of current PEMFC technology is their high cost, in large part due to the use of platinum-based catalysts, especially in catalyzing the inherently sluggish oxygen reduction reaction (ORR) process at the cathode.[2] Pyrolyzed carbon materials incorporated with inexpensive transition metals (e.g., Fe and Co) and nitrogen (metal–nitrogen–carbon (M–N–C)) represent the most promising candidates to potentially substitute Pt-based catalysts in PEMFCs.[3] Recent studies have suggested that metal atoms with corresponding N-coordinations (denoted as MNx moieties) hosted within a carbon matrix can serve as catalytic centers Transition metal atoms with corresponding nitrogen coordination are widely proposed as catalytic centers for the oxygen reduction reaction (ORR) in metal–nitrogen–carbon (M–N–C) catalysts. Here, an effective strategy that can tailor Fe–N–C catalysts to simultaneously enrich the number of active sites while boosting their intrinsic activity and utilization is reported. This is achieved by edge engineering of FeN4 sites via a simple ammonium chloride salt-assisted approach, where a high fraction of FeN4 sites are preferentially generated and hosted in a graphene-like porous scaffold. Theoretical calculations reveal that the FeN4 moieties with adjacent pore defects are likely to be more active than the nondefective configuration. Coupled with the facilitated accessibility of active sites, this prepared catalyst, when applied in a practical H2–air proton exchange membrane fuel cell, delivers a remarkable peak power density of 0.43 W cm−2, ranking it as one of the most active M–N–C catalysts reported to date. This work provides a new avenue for boosting ORR activity by edge manipulation of FeN4 sites. Fuel Cells

Journal ArticleDOI
TL;DR: Because of their interesting structures and bonding and potentials as motifs for new nanomaterials, size-selected boron clusters have received tremendous interest in recent years and have allowed systematic joint photoelectron spectroscopy and theoretical studies, revealing predominantly two-dimensional structures.
Abstract: Because of their interesting structures and bonding and potentials as motifs for new nanomaterials, size-selected boron clusters have received tremendous interest in recent years. In particular, boron cluster anions (Bn−) have allowed systematic joint photoelectron spectroscopy and theoretical studies, revealing predominantly two-dimensional structures. The discovery of the planar B36 cluster with a central hexagonal vacancy provided the first experimental evidence of the viability of 2D borons, giving rise to the concept of borophene. The finding of the B40 cage cluster unveiled the existence of fullerene-like boron clusters (borospherenes). Metal-doping can significantly extend the structural and bonding repertoire of boron clusters. Main-group metals interact with boron through s/p orbitals, resulting in either half-sandwich-type structures or substitutional structures. Transition metals are more versatile in bonding with boron, forming a variety of structures including half-sandwich structures, metal-centered boron rings, and metal-centered boron drums. Transition metal atoms have also been found to be able to be doped into the plane of 2D boron clusters, suggesting the possibility of metalloborophenes. Early studies of di-metal-doped boron clusters focused on gold, revealing ladder-like boron structures with terminal gold atoms. Recent observations of highly symmetric Ta2B6− and Ln2Bn− (n = 7–9) clusters have established a family of inverse sandwich structures with monocyclic boron rings stabilized by two metal atoms. The study of size-selected boron and doped-boron clusters is a burgeoning field of research. Further investigations will continue to reveal more interesting structures and novel chemical bonding, paving the foundation for new boron-based chemical compounds and nanomaterials.

Journal ArticleDOI
TL;DR: A new strategy to mediate the CsPbI2Br crystallization by directly doping the copper (II) bromide (CuBr2) into a perovskite precursor is developed, resulting in a high quality all-inorganic perovSKite film with enlarged grain size, improved carrier nobilities and reduced trap states.
Abstract: All-inorganic-based perovskites achieved by replacing the organic component with cesium (Cs) have drawn more attention because of their intrinsic inorganic stability. However, the cell efficiency in all-inorganic perovskite solar cells is still far below that in organic-inorganic hybrid perovskite-based devices. Here, we develop a new strategy to mediate the CsPbI2Br crystallization by directly doping copper(II) bromide (CuBr2) into a perovskite precursor. The incorporation of CuBr2 played a role in retarding the crystallization dynamics process of CsPbI2Br film, resulting in a high-quality all-inorganic perovskite film with enlarged grain size, improved carrier mobilities, and reduced trap states. The fabricated perovskite solar cells delivered a champion power conversion efficiency of 16.15%, which is the highest efficiency in CsPbI2Br based all-inorganic perovskite solar cells and largely higher than 13.24% for pristine CsPbI2Br based device. The developed doping method paves a new route to fabricate high-performance all-inorganic perovskite solar cells.

Journal ArticleDOI
TL;DR: In this article, a perovskite solar cell (PSC)-driven photo-rechargeable lithium-ion capacitor (LIC) was used for self-powered wearable strain sensors.

Journal ArticleDOI
TL;DR: In this paper, the performance of hexagonal WO3 nanosheets with and without dominant (0 0 1) facets (Cu2O/WO3-001 and Cu2O /WO 3-3) was evaluated in the presence of H2O vapour under visible light irradiation.
Abstract: Systematical design and controllable assembly of nanostructured photocatalysts have received much attention in the field of CO2 reduction. The Cu2O decroted hexagonal WO3 nanosheets with and without dominant (0 0 1) facets (Cu2O/WO3-001 and Cu2O/WO3) were synthesized vertically on the surface of fluorine-doped stannic oxide (FTO) substrate and their photocatalytic performance for CO2 reduction were evaluated in the presence of H2O vapour under visible light irradiation (λ > 400 nm). The Cu2O/WO3-001 catalyst exhibited higher photocatalytic activity than those of Cu2O, WO3-001 and Cu2O/WO3. The maximal product yields of CO, O2 and H2 for Cu2O/WO3-001 after 24 h illumination reached 11.7, 5.7 and 0.7 μmol, respectively, and good cycling ability was discovered after 4 cycles. The (0 0 1) facet of hexagonal phase WO3 nanosheet was in favor of the H2O oxidation in the CO2 reduction process. Additionally, the Z-scheme charge transfer mode of Cu2O/WO3 heterojunction could promote photoinduced charge separation and enhance redox ability of the separated electrons and holes, leading to excellent photocatalytic CO2 reduction performance. The study may provide some insights into the coherent design of specific nanosheet photocatalysts with Z-scheme charge transfer for CO2 reduction.

Journal ArticleDOI
TL;DR: Gen expression bias across surveyed tissues such that subgenome B is more dominant in homoeologous expression is found, and CG methylation in promoter regions may play an important role in altering gene expression in allotetraploid C. carpio.
Abstract: Common carp (Cyprinus carpio) is an allotetraploid species derived from recent whole genome duplication and provides a model to study polyploid genome evolution in vertebrates. Here, we generate three chromosome-level reference genomes of C. carpio and compare to related diploid Cyprinid genomes. We identify a Barbinae lineage as potential diploid progenitor of C. carpio and then divide the allotetraploid genome into two subgenomes marked by a distinct genome similarity to the diploid progenitor. We estimate that the two diploid progenitors diverged around 23 Mya and merged around 12.4 Mya based on the divergence rates of homoeologous genes and transposable elements in two subgenomes. No extensive gene losses are observed in either subgenome. Instead, we find gene expression bias across surveyed tissues such that subgenome B is more dominant in homoeologous expression. CG methylation in promoter regions may play an important role in altering gene expression in allotetraploid C. carpio.

Journal ArticleDOI
TL;DR: The first enantioselective addition of prochiral radicals to vinylpyridines under cooperative photoredox and asymmetric catalysis mediated by visible light is described and valuable chiral γ-secondary/tertiary hydroxyl- and amino-substituted pyridine derivatives were obtained.
Abstract: Pyridine, one of the most important azaarenes, is ubiquitous in functional molecules. The electronic properties of pyridine have been exploited to trigger asymmetric transformations of prochiral species as a direct approach for accessing chiral pyridine derivatives. However, the full potential of this synthetic strategy for the construction of enantioenriched γ-functionalized pyridines remains untapped. Here, we describe the first enantioselective addition of prochiral radicals to vinylpyridines under cooperative photoredox and asymmetric catalysis mediated by visible light. The enantioselective reductive couplings of vinylpyridines with aldehydes, ketones, and imines were achieved by employing a chiral Bronsted acid to activate the reaction partners and provide stereocontrol via H-bonding interactions. Valuable chiral γ-secondary/tertiary hydroxyl- and amino-substituted pyridines were obtained in high yields with good to excellent enantioselectivities.

Journal ArticleDOI
TL;DR: In this paper, the authors developed lead halide perovskite quantum dot (QD) solar cells with a combinational absorbing layer based on stacked α-CsPbI3 and FAPbI4.
Abstract: We developed lead halide perovskite quantum dot (QD) solar cells with a combinational absorbing layer based on stacked α-CsPbI3 and FAPbI3. α-CsPbI3 QDs, with a relatively wide bandgap of 1.75 eV, ...

Journal ArticleDOI
TL;DR: The result shows that both the surface-bound SO4- and OH play significant roles during the degradation process, where the electron transfer of Co2+/Co3+, Bi3+/Bi5+, and Ni2/Ni3+ realizes the sustained regeneration of the active radicals.

Journal ArticleDOI
TL;DR: In this paper, a broad spectrum N-doped carbon quantum dot/TiO2 nanosheet with higher surface energy {0,0, 1} faceted (NCDS/TNS-001) composites with significantly improved broad-spectrum utilization was reported.