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Despite the fact that d‐band center theory links the d electron structure of transition metals to their catalytic activity, it is yet unknown how the synergistic effect of multi‐d electrons impacts catalytic performance. Herein, novel LaNi1‐xCoxRu intermetallics containing 5d, 4d, and 3d electrons were prepared. In these compounds, the 5d orbital of La transfers electrons to the 4d orbital of Ru, which provides adsorption sites for H*. The 3d orbitals of Ni and Co interact with the 5d and 4d orbitals to generate an anisotropic electron distribution, which facilitates the adsorption and desorption of OH*. The synergistic effect of multi‐d electrons ensures efficient catalytic activity. The optimized LaNi0.5Co0.5Ru has an overpotential of 43mV at 10 mA cm−2 for alkaline electrocatalytic hydrogen evolution reaction. Beyond offering a variety of new electrocatalysts, this work reveals the multi‐d electron synergy in promoting catalytic reaction. [ABSTRACT FROM AUTHOR]

Despite the fact that d‐band center theory links the d electron structure of transition metals to their catalytic activity, it is yet unknown how the synergistic effect of multi‐d electrons impacts catalytic performance. Herein, novel LaNi1‐xCoxRu intermetallics containing 5d, 4d, and 3d electrons were prepared. In these compounds, the 5d orbital of La transfers electrons to the 4d orbital of Ru, which provides adsorption sites for H*. The 3d orbitals of Ni and Co interact with the 5d and 4d orbitals to generate an anisotropic electron distribution, which facilitates the adsorption and desorption of OH*. The synergistic effect of multi‐d electrons ensures efficient catalytic activity. The optimized LaNi0.5Co0.5Ru has an overpotential of 43mV at 10 mA cm−2 for alkaline electrocatalytic hydrogen evolution reaction. Beyond offering a variety of new electrocatalysts, this work reveals the multi‐d electron synergy in promoting catalytic reaction. [ABSTRACT FROM AUTHOR]

Molybdenum diselenide and cobalt diselenide have been commonly implemented in electrocatalytic hydrogen evolution reaction (HER). However, there have been few research on the creation of their three‐phase heterojunctions and the associated HER process. Herein, we constructed a three‐phase heterostructure sample consisting of orthorhombic CoSe2, cubic CoSe2 and MoSe2 and we investigated its HER performance. The sample shows microsphere morphology composed of nanosheets with interfacial interactions between the components. It possesses an overpotential of −136 mV at −10 mA cm−2 in acid medium, which is superior to that of single component and most two‐phase heterostructures. Especially, the overpotential at −200 mA cm−2 is smaller than that of Pt/C. The excellent performance can be attributed to the d‐orbital upshift of the Co active sites due to charge redistribution between the three‐phase heterojunction and the optimization of the hydrogen free energy. This work provides inspiration for exploring the application of other multi‐component heterojunctions in electrocatalytic hydrogen evolution. [ABSTRACT FROM AUTHOR]

High temperature is a major stress in rice production. Although considerable progress has been made in investigating heat tolerance (HT) in rice, the genetic basis of HT at the heading stage remains largely unknown. In this study, a novel set of chromosome segment substitution lines (CSSLs) consisting of 113 lines derived from a heat-resistant indica variety N22 and a heat-sensitive indica variety 9311 was developed and used for the analysis of the genetic basis of HT. The heat sensitivity index (HSI) calculated based on seed-setting rates under natural and high-temperature environments was used to evaluate the influence of HT at the rice heading stage. In total, five quantitative trait loci (QTLs) associated with HT were detected based on seed-setting rate (SSR) evaluation; these were named qSSR6-1, qSSR7-1, qSSR8-1, qSSR9-1 and qSSR11-1 located on chromosomes 6, 7, 8, 9 and 11, respectively. Heat-tolerant alleles of the QTLs were all derived from N22. Among them, qSSR9-1 overlapped with QTLs identified previously, while the remaining QTLs were found novel. In particular, qSSR7-1 explained a high phenotypic variation of 26.35% with a LOD score of 10.75, thus deserved to be further validated. These findings will increase our understanding of the genetic mechanism underlying HT and facilitate the breeding of heat-tolerant rice varieties. [ABSTRACT FROM AUTHOR]

The construction of heterostructures is a versatile tactic to enhance catalytic activity. However, it is still elusive to realize the modulation of the interlayer spacing in this way to further improve the performance. Here, strong interfacial coupling between CoSe2 and MoSe2 by constructing CoSe2/MoSe2 heterostructures is achieved. The interlayer spacing of MoSe2 is compressed by 0.3 Å. The enhanced charge transfer is validated by X‐ray absorption spectroscopy and X‐ray photoelectron spectroscopy. Coupled with the morphology of hollow microtubes, which can facilitate the exposure of active sites, CoSe2/MoSe2 heterostructures reported here exhibit high activity (119 mV at 10 mA cm−2) and excellent stability with small degradation after 50 h operation, surpassing other analogous powdered electrocatalysts. This work sheds light on the importance of tuning the interlayer spacing to improve electrocatalytic activity. [ABSTRACT FROM AUTHOR]

The discovery and identification of novel active sites are paramount for deepening the understanding of the catalytic mechanism and driving the development of remarkable electrocatalysts. Here, we reveal that the genuine active sites for the hydrogen evolution reaction (HER) in LaRuSi are Si sites, not the usually assumed Ru sites. Ru in LaRuSi has a peculiar negative valence state, which leads to strong hydrogen binding to Ru sites. Surprisingly, the Si sites have a Gibbs free energy of hydrogen adsorption that is near zero (0.063 eV). The moderate adsorption of hydrogen on Si sites during the HER process is also validated by in situ Raman analysis. Based on it, LaRuSi exhibits an overpotential of 72 mV at 10 mA cm−2 in alkaline media, which is close to the benchmark of Pt/C. This work sheds light on the recognition of real active sites and the exploration of innovative silicide HER electrocatalysts. [ABSTRACT FROM AUTHOR]

The discovery and identification of novel active sites are paramount for deepening the understanding of the catalytic mechanism and driving the development of remarkable electrocatalysts. Here, we reveal that the genuine active sites for the hydrogen evolution reaction (HER) in LaRuSi are Si sites, not the usually assumed Ru sites. Ru in LaRuSi has a peculiar negative valence state, which leads to strong hydrogen binding to Ru sites. Surprisingly, the Si sites have a Gibbs free energy of hydrogen adsorption that is near zero (0.063 eV). The moderate adsorption of hydrogen on Si sites during the HER process is also validated by in situ Raman analysis. Based on it, LaRuSi exhibits an overpotential of 72 mV at 10 mA cm−2 in alkaline media, which is close to the benchmark of Pt/C. This work sheds light on the recognition of real active sites and the exploration of innovative silicide HER electrocatalysts. [ABSTRACT FROM AUTHOR]

The separate modulation of the adsorption of *O and *OOH is challenging in oxygen evolution reaction (OER), which results in a large overpotential and slow kinetics. To balance the adsorption of the two active species, here, a way to regulate the local spin state and band structure simultaneously in Ni3S2 nanosheets is reported. The adequate doping of W heteroatoms causes the electron depletion from the Ni active site, which modulates the spin state of eg electrons, weakening the adsorption of *O. Additionally, the introduction of S vacancies contributes to the upshift of the d band center, which strengthens the adsorption of *OOH. In this manner, the adsorption of Ni3S2 for the active intermediates is optimized, resulting in a considerably improved overpotential of 246 mV at 100 mA cm−2 and a Tafel slope of 66 mV dec−1. This work provides insights into the exploration of OER catalysts through synergistic modulation of the spin state and the band structure. [ABSTRACT FROM AUTHOR]

Tuberculosis (TB) is the world's most prevalently infectious disease. Molecular mechanisms behind tuberculosis remain unknown. microRNA (miRNA) is involved in a wide variety of diseases. To validate the significant genes and miRNAs in the current sample, two messenger RNA (mRNA) expression profile datasets and three miRNA expression profile datasets were downloaded from the Gene Expression Omnibus (GEO) database. The differentially expressed (DE) genes (DEGs) and miRNAs (DE miRNAs) between healthy and TB patients were filtered out. Enrichment analysis was executed, and a protein-protein interaction (PPI) network was developed to understand the enrich pathways and hub genes of TB. Additionally, the target genes of miRNA were predicted and overlapping target genes were identified. We studied a total of 181 DEGs (135 downregulated and 46 upregulated genes) and two DE miRNAs (2 downregulated miRNAs) from two gene profile datasets and three miRNA profile datasets, respectively. 10 hub genes were defined based on high degree of connectivity. A PPI network's top module was constructed. The 23 DEGs identified have a significant relationship with miRNAs. 25 critically significant Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways were discovered. The detailed study revealed that, in tuberculosis, the DE miRNA and DEGs form an interaction network. The identification of novel target genes and main pathways would aid with our understanding of miRNA's function in tuberculosis progression. [ABSTRACT FROM AUTHOR]

Optimizing the hydrogen adsorption Gibbs free energy (ΔGH) of active sites is essential to improve the overpotential of the electrocatalytic hydrogen evolution reaction (HER). We doped graphene‐like Co0.85Se with sulfur and found that the active sites are reversed (from cationic Co sites to anionic S sites), which contributed to an enhancement in electrocatalytic HER performance. The optimal S‐doped Co0.85Se composite has an overpotential of 108 mV (at 10 mA cm−2) and a Tafel slope of 59 mV dec−1, which exceeds other reported Co0.85Se‐based electrocatalysts. The doped S sites have much higher activity than the Co sites, with a hydrogen adsorption Gibbs free energy (ΔGH) close to zero (0.067 eV), which reduces the reaction barrier for hydrogen production. This work provides inspiration for optimizing the intrinsic HER activity of other related transition metal chalcogenides. [ABSTRACT FROM AUTHOR]

Optimizing the hydrogen adsorption Gibbs free energy (ΔGH) of active sites is essential to improve the overpotential of the electrocatalytic hydrogen evolution reaction (HER). We doped graphene‐like Co0.85Se with sulfur and found that the active sites are reversed (from cationic Co sites to anionic S sites), which contributed to an enhancement in electrocatalytic HER performance. The optimal S‐doped Co0.85Se composite has an overpotential of 108 mV (at 10 mA cm−2) and a Tafel slope of 59 mV dec−1, which exceeds other reported Co0.85Se‐based electrocatalysts. The doped S sites have much higher activity than the Co sites, with a hydrogen adsorption Gibbs free energy (ΔGH) close to zero (0.067 eV), which reduces the reaction barrier for hydrogen production. This work provides inspiration for optimizing the intrinsic HER activity of other related transition metal chalcogenides. [ABSTRACT FROM AUTHOR]

Abstract To design efficient photocatalysis system, the recombination of electron-hole pairs in photocatalysts should be suppressed. Herein, p type Cu 2−x Se/n type CdS composite photocatalyst was proposed for the first time to improve photocatalysis performance for Rhodamine B (RhB) degradation. Among the various ratio composites, 10 wt% Cu 2−x Se/CdS shows the best photocatalysis performance, the degradation rate of RhB was enhanced 7.8 times than that of pristine CdS. The enhanced photocatalysis performance was mainly ascribed to the formation of Cu 2−x Se/CdS p-n junction, which will lead to effective charge separation in the composite photocatalyst. Graphical abstract Unlabelled Image Highlights • A novel composite photocatalyst of Cu 2−x Se/CdS was synthesized. • Cu 2−x Se/CdS p-n junction can reduce the recombination of electron-hole. • 10 wt% Cu 2−x Se/CdS exhibits optimized photocatalysis active. • Photocatalytic mechanism of Cu 2−x Se/CdS was proposed. [ABSTRACT FROM AUTHOR]

Abstract It is a fascinating question whether it exists and how to explore Co-based high-temperature superconductors, since Co is next to Fe and has just one more electron than Fe. Based on this, SrCo 2 As 2 has attracted great research interest due to its similar magnetic ground state to Fe-based superconductors. Here, we studied the electron doping effect of SrCo 2 As 2 by doping 2.5% Nd at the Sr sites. Our experimental results show that injecting electrons caused by this doping can induce it from paramagnetism to ferromagnetism. The first-principles calculation indicates that the density of states at the Fermi surface is high enough, which tends to be related to ferromagnetism. This work provides a general strategy for inducing ferromagnetism in Stoner paramagnetic systems. Graphical abstract Unlabelled Image Highlights • Injecting a small amount of electrons induces SrCo 2 As 2 from paramagnetism to ferromagnetism. • The first-principles calculations indicate that SrCo 2 As 2 should be in a critical state between paramagnetism and ferromagnetism. • The crystal structure of Sr 0.975 Nd 0.025 Co 2 As 2 is determined by Rietveld refinement method. • This work provides a general strategy for inducing ferromagnetism in Stoner paramagnetic systems. [ABSTRACT FROM AUTHOR]

A new porous material, alveolate Cu2−xSe microsheets, was synthesized through a simple one-step solvothermal process. The surface morphology and microstructure of the as-prepared Cu2−xSe were characterized by various techniques. It was found that the as-synthesized Cu2−xSe has hierarchical porosity composed of mesopores and macropores, and rich active surfaces of {111} facets. A noteworthy visible-light-responsive photocatalytic discoloration of Rhodamine B was observed for the as-developed alveolate Cu2−xSe microsheets. The superior photocatalytic properties demonstrated by the as-synthesized Cu2−xSe are mainly attributed to the highly accessible active surfaces of the {111} facets and the wider light absorption range resulting from its narrower band gap. [ABSTRACT FROM AUTHOR]

Photocatalysis is an effective technique to remove antibiotic residues from aquatic environments. Typical metal sulfides like Zn3In2S6 have been applied to a wide range of photocatalytic applications. However, there are currently no readily accessible methods to increase its antibiotic‐degrading activity. Here, a facile hydrothermal approach is developed for the preparation of flower‐like Zn3In2S6 with tunable sulfur lattice defects. Photogenerated carriers can be separated and transferred more easily when there is an adequate amount of lattice defects. Moreover, lattice defect‐induced electronic modulation enhances light utilization and adsorption properties. The modified Zn3In2S6 demonstrates outstanding photocatalytic degradation activity for levofloxacin, ofloxacin, and tetracycline. This work sheds light on exploring metal sulfides with sulfur lattice defects for enhancing photocatalytic activity. [ABSTRACT FROM AUTHOR]

Theorigin of transition metal vacancies and their effects on theproperties of ThCr2Si2-type compounds have beenless studied and poorly understood. Here we carefully investigatethe structure, physical properties, and electronic structure for aseries of lanthanum cobalt arsenides with nominal composition of LaCoxAs2(1.6 ≤ x≤ 2.1). It is revealed that the occupancy of Co can be tunedbetween 1.98(1) and 1.61(1). The structural analyses based on X-rayand neutron diffractions show the existence of Co vacancies resultsfrom charge balance due to the formation of bond between As–As.These Co vacancies affect the magnetic and electrical properties greatly,adjusting the Curie temperature from 205 to 47 K and increasing theresistivity by more than 100%. First-principles calculations indicatethat the Co vacancies weaken the spin polarization and reduce thedensity of states at the Fermi level, resulting in decreased Curietemperature and increased resistivity, respectively. Our results addressthe importance of transition metal vacancies in ThCr2Si2-type materials and offer a reliable route to tune the magnetismof ThCr2Si2-type structure. [ABSTRACT FROM AUTHOR]

• A series of BiVO 4 samples composited with NiSe 2 nanosheets were prepared through a facile solvothermal method. • The photocatalytic degradation rate of RhB of the optimized sample reaches 11 times higher than that of pure BiVO 4. • The Schottky junction derived from the discrepancy of work function accelerates the separation of photogenerated carriers. • The interaction at the interface reduces the band gap of BiVO 4. The rapid recombination of photogenerated carriers limits the photocatalytic activity of BiVO 4. Here, we grew NiSe 2 nanosheets on the surface of BiVO 4 through a facile solvothermal method to construct a Schottky junction. Due to the discrepancy of work function, electrons at the interface are transferred from BiVO 4 to NiSe 2 , thereby forming a built-in electric field. In virtue of the built-in electric field and the good conductivity of NiSe 2 , the photo-generated carriers can be quickly separated and transferred. In addition, the interaction at the interface reduces the band gap of BiVO 4 , which increases the absorption of visible light. These above benefits improve the photocatalytic performance. The photocatalytic reaction under visible light shows that the degradation rate of RhB for 9 mol% NiSe 2 composited BiVO 4 increases by 11 times compared with pure BiVO 4. The simplicity of the preparation method and the significantly improved performance show the enormous potential of NiSe 2 to be coupled with other semiconductor photocatalysts to improve their catalytic activity. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To assess the value of Fourier-transform infrared (FT-IR) spectroscopic analysis in detecting colorectal carcinoma. METHODS: Fifty pairs of specimens of exfoliated cells from patients with colorectal carcinoma, who had undergone colorectal resection, were analyzed by using FT-IR spectrometry. Exfoliated cells were obtained by scraping off: (i) the foci of the colorectal carcinoma; and (ii) the normal mucosa more than 5 cm away from the foci. Cell specimens were fixed and smeared onto two slides: a gold-coated slide for the infrared spectrometry and a conventional one for histopathological evaluation. The spectra from 28 pairs of specimens were analyzed by logistic regression with multiple factors to establish a statistical model for predicting the probability of colorectal cancers, and then the spectra of the remaining 22 pairs were judged according to the model. Their corresponding diagnostic accuracy was calculated. RESULTS: Substantial differences were found in the spectral properties of cancer and non-cancer cells, which were evident in the frequency region of 1000–1350/cm. A shift of the phosphodiester groups of nucleic acids was noted: compared with the spectral features of non-cancerous cells, the distance between VsPO2– and VasPO2– was shorter in cancerous cells. The C–O stretching bonds of cell proteins were significantly changed in the frequency region of 1140–1180/cm. In non-cancerous cells, the peak intensity of 1155/cm was stronger than that of 1174/cm, whereas in cancerous cells the peak intensity of 1155/cm was weaker than that of 1174/cm; the peak intensity ratio of 1174/cm: 1155/cm was increased in cancerous cells. The spectral characteristics of the spectrometric data from the 22 pairs of specimens were consistent with those of the base-model data. The other 22 pairs of specimens were analyzed according to the model, indicating that Fourier-transform... [ABSTRACT FROM AUTHOR]

Cobalt phosphosulphide (CoPS) has recently been recognized as a potentially effective electrocatalyst for the hydrogen evolution reaction (HER). However, there have been no research on the design of CoPS‐based heterojunctions to boost their HER performance. Herein, CoPS/Co4S3 heterojunction was prepared by phosphating treatment based on defect‐rich flower‐like Co1‐xS precursors. The high specific surface area of nanopetals, together with the heterojunction structure with inhomogeneous strain, exposes more active sites in the catalyst. The electronic structure of the catalyst is reconfigured as a result of the interfacial interactions, which promote the catalyst‘s ability to adsorb hydrogen and conduct electricity. The synergistic effect of the Co and S dual‐site further enhance the catalytic activity. The catalyst has overpotentials of 61 and 70 mV to attain a current density of 10 mA cm−2 in acidic and alkaline media, respectively, which renders it competitive with previously reported analogous catalysts. This work proposes an effective technique for constructing transition metal phosphosulfide heterojunctions, as well as the development of an efficient HER electrocatalyst. [ABSTRACT FROM AUTHOR]

The surface reconstruction of electrochemically activated catalysts is an effective way to improve performance. However, there is currently a dearth of study on the surface reconstruction of silicide catalysts for hydrogen evolution reactions (HER). Here, a new HER electrocatalyst, LaRuSi3, is synthesized and electrochemically triggered it to produce Ru clusters on its surface. Experimental data and theoretical simulations reveal that Ru clusters optimize the charge distribution of LaRuSi3, which promotes the adsorption of water by Ru sites and improves the adsorption of hydrogen by Si sites. The conductivity and electrochemical active sites of the catalysts are also enhanced. The catalyst has an overpotential of 45 mV to attain a current density of 10 mA cm−2 in alkaline media, which exceeds the majority of other Ru‐based compounds. This work contributes to the exploration of more efficient novel silicides HER electrocatalysts and broadens the application of surface reconstruction techniques. [ABSTRACT FROM AUTHOR]

Mesoporous graphitic carbon nitride (g-C 3 N 4) nanosheets are fabricated by ultrasonically exfoliating the bulk g-C 3 N 4 in sulfuric acid aqueous solution. In comparison with the bulk counterpart, the as-prepared g-C 3 N 4 nanosheets have a higher specific surface area, narrower bandgap, better light response and lower charge transfer resistance. Consequently, the mesoporous g-C 3 N 4 nanosheets exhibit a 3.3-fold photocatalytic hydrogen evolution when irradiated with visible light. The improved photocatalytic performance of the g-C 3 N 4 nanosheets is mainly because of the increased specific surface area, abundant mesopores and narrowed bandgap, which would increase the reactive sites, shorten carriers transfer paths and improve their light absorption ability as well. A liquid-phase ultrasonic exfoliation strategy is utilized to fabricate mesoporous g-C 3 N 4 nanosheets (CNS), which demonstrate narrowed bandgap and considerably improved photocatalytic hydrogen generation. [Display omitted] • Ultrasonic exfoliation strategy is used to fabricate carbon nitride nanosheets (CNS). • CNS has a large specific surface area along with abundant mesopores. • CNS exhibits narrower bandgap and better light response than the bulk CN. • CNS reveals significantly enhanced photocatalytic H 2 generation. • The enhancement is due to improved light response and separation of photo-generated charges. [ABSTRACT FROM AUTHOR]

Sluggish electron kinetics in the oxygen evolution reaction (OER) is one of the main factors restricting the development of hydrogen production technology from electrical water splitting, while the key to breaking through the bottleneck is to develop low-cost and efficient OER electrocatalysts. Here, a scheme for regulating the phase of electrocatalysts using carbon nanotubes is proposed, which significantly boosts the OER activity of transition metal complexes, exhibiting comparable electrocatalytic performance to noble metals. In this process, an organic complex of cobalt was combined with carbon nanotubes that prevent the catalyst from crystallizing during vulcanization, with sulfur atoms replacing some of oxygen atoms to further modify the active center. The as-fabricated amorphous CoOxSy complex showed excellent OER activity with a unique electronic structure, resulting in overpotentials of 290 mV and 330 mV at current densities of 10 mA cm−2 and 100 mA cm−2, respectively, and a Tafel slope of 50.8 mV dec−1. Moreover, the participation of carbon nanotubes further enhanced the electrochemical stability of the catalyst, which exhibited consistent performance in stability tests up to 60 hours. The results demonstrate the potential of carbon-based amorphous transition metal complexes as highly active electrocatalysts and provide a new possibility to design efficient catalysts by phase engineering. [ABSTRACT FROM AUTHOR]

• The correlation between structures and the T c in FeSe-family is presented for the first time. • The distorted FeSe 4 tetrahedron plays an important role in understanding the superconductivity. • The electronic correlation and FS nesting between electron pockets are associated with distorted FeSe 4 tetrahedron. • The crystal structure of N 0.81(1) D 3.24(2) Fe 2 Se 2 is determined by neutron and x-ray powder diffraction. We demonstrate that unique cation, ND 4 (1−δ)+, exists between FeSe layers and induces a large distortion of the FeSe 4 tetrahedron in N 0.81(1) D 3.24(2) Fe 2 Se 2 by neutron and X-ray powder diffraction. The electronic correlations of the Fe 3d electrons and Fe d xy , d yz and d xz band widths could be tuned by changing the FeSe 4 tetrahedron distortion, revealing the importance of lattice distortion to the superconductivity of FeSe-based intercalates. [ABSTRACT FROM AUTHOR]

• The post-treatment technique via pulsed laser irradiation was developed. • The Schottky junction between Cd clusters and CdS was in-situ formed on CdS surfaces. • The rate of hydrogen evolution over in the first hour is 40-times than that of pure CdS. • The Schottky junction between Cd clusters and CdS reduce electron-hole recombination. Herein, we developed one simple and novel post-treatment technique via pulsed laser irradiation of CdS (L-CdS) semiconductor to significantly enhance the visible light-driven hydrogen evolution performance from water splitting, during which the rate of hydrogen evolution over L-CdS in the first hour is 40-times than that of pure CdS. Because the pulsed laser irradiation induces the in-situ formation of metallic Cd clusters on CdS surface to construct the Schottky junction between Cd clusters and CdS, obviously facilitating the electron transfer from excited CdS into Cd to endow more photogenerated electrons for enhancing the photocatalytic efficiency of H 2 evolution. Moreover, the bandgap narrow of post-treated CdS also benefits the stronger light absorption for enhancing the photocatalytic efficiency. This work may provide a new approach to develop heterojunction-based photocatalysts for efficient solar-to-chemical conversion. [ABSTRACT FROM AUTHOR]

The fabrication of heterojunctions is an intriguing approach to boost the reactivity of catalysts. However, facile preparation of desirable heterojunction materials remains a challenge. Here, novel CoPS3/CoS2 heterojunctions are created by an intuitive phosphatization process on the basis of structurally flexible cobalt sulfide precursors. Significant stress effect exists at these heterogeneous interfaces, resulting in lattice distortions and the exposure of more active sites. The interface interaction also modifies the catalyst's electronic structure to improve its electrical conductivity and hydrogen adsorption capabilities. Notably, the overpotential of the CoPS3/CoS2 heterojunction for electrocatalytic hydrogen evolution reaction is just 36.3 mV, which is far superior to those of single‐component catalysts and competitive with comparable catalysts reported. This work not only offers an innovative electrocatalyst but also a strategy that can be used to create heterojunctions based on related transition metal thiophosphates. [ABSTRACT FROM AUTHOR]

Well-designed nanostructures are very important for the electrochemical performance of lithium-ion electrode materials. In order to improve the electrochemical performance of ZnO-based anode materials, ZnO/Ni composite film, assembled by ordered hollow microsphere arrays, is designed and fabricated by means of magnetron sputtering technique using a colloidal crystal template composed of a monolayer of ordered polystyrene (PS) microspheres. The ordered hollow microsphere structure as well as the constituent Ni component of the ZnO/Ni film show major advantages of homogenizing electrode reactions, enhancing electrode reaction kinetics and accommodating volume change of active materials, so they can reduce electrode polarization and stabilize electrode structure. Consequently, the resulting ordered ZnO/Ni hollow microspheres arrays deliver an initial charge capacity of 685 mAh g−1, an initial coulombic efficiency of 68%, and a capacity retention rate of 69% after 100 cycles, all of which are higher than those of the pure ZnO film. These results show progress in developing more stable ZnO-based anode materials for lithium ion batteries. [ABSTRACT FROM AUTHOR]

The hydrogen spillover effect has garnered considerable attention as a promising avenue to enhance the activity of the hydrogen evolution reaction (HER) in metal‐support compound materials. Herein, Pt atom dimers on the NiOOH support are successfully synthesized with a reversed hydrogen spillover effect, demonstrating much better alkaline HER activity than Pt single atoms and Pt clusters. Atomic and electronic structure characterizations unequivocally verify the anchoring of Pt atom dimers on NiOOH through Pt─O bonds, thus obtaining a reversed and enhanced hydrogen spillover effect. Theoretical and experimental results indicate that NiOOH exhibits pronounced water dissociation capability, while the Pt atom dimers, in comparison to Pt single atoms and Pt clusters, demonstrate superior hydrogen desorption ability. The reversed spillover with Pt atom dimers leads to remarkable HER activity in alkaline solutions, as evidenced by an ultra‐small overpotential of 13 mV at 10 mA cm−2. These findings not only provide insights into the potential use of atom dimers for HER, but also shed light on reversed spillover in designing high‐performance catalysts. [ABSTRACT FROM AUTHOR]

Graphene-based free-space optical modulators are usually enabled by shifting electrically the resonant frequency of a plasmonic or optical resonator. However, this resonance-shifting approach could lead to a potential loss of the on/off ratio, considering the fact that photodetectors always respond in a spectral range. Here, to modulate directly the amplitude of mid-infrared light, we propose a graphene-based modulator employing a graphene layer and a magnetic plasmonic array. With this novel design, the transmission intensity through the plasmonic array can be modulated in a direct manner without shifting the transmission peak. Magnetic plasmon resonance (MPR) accounts for the observed transmission, while Wood anomaly (WA) is utilized to fix the resonant position. The proposed modulator shows an excellent tolerance upon variation of structure parameters, with an insertion loss as low as 0.7 dB and a typical on/off ratio of 20, as well as a large modulation depth of 95%. This work offers a new route to design graphene-based optical modulators and may find applications in planar optics and the free-space optical (FSO) communication. [ABSTRACT FROM AUTHOR]

The electrocatalytic hydrogen evolution activity of transition metal sulfide heterojunctions are significantly increased when compared with that of a single component, but the mechanism behind the performance enhancement and the preparation of catalysts with specific morphologies still need to be explored. Here, we prepared a Co9S8/MoS2 heterojunction with microsphere morphology consisting of thin nanosheets using a facile two-step method. There is electron transfer between the Co9S8 and MoS2 of the heterojunction, thus realizing the redistribution of charge. After the formation of the heterojunction, the density of states near the Fermi surface increases, the d-band center of the transition metal moves downward, and the adsorption of both water molecules and hydrogen by the catalyst are optimized. As a result, the overpotential of Co9S8/MoS2 is superior to that of most relevant electrocatalysts reported in the literature. This work provides insight into the synergistic mechanisms of heterojunctions and their morphological regulation. [ABSTRACT FROM AUTHOR]

Alloying noble metals with non‐noble metals is a promising method to fabricate catalysts, with the advantages of reduced noble metal usage and excellent activity. In this work, electron‐abundant Ir/Rh sites, as highly active centers for the hydrogen evolution reaction (HER), are realized by fabricating Ir1−xRhxSb alloys through the arc‐melting method. The electron transfer from Sb to Ir/Rh makes the latter negatively charged, leading to considerably optimized adsorption for active H species during HER. As a result, the Ir1−xRhxSb alloy exhibits outstanding activity for HER, with an optimized overpotential of 22 mV at 10 mA cm–2 and a Tafel slope of 47.6 mV dec–1. This work provides insights into highly active alloys and sheds light on the utilization of electron‐abundant metal atoms. [ABSTRACT FROM AUTHOR]

The coordination environment is crucial for the activity of an electrocatalyst, which defines the interaction between the central and adjacent atoms. In traditional 2D MX2 (M = Mo, W, etc., X = S, Se), M is usually coordinated with 6 X atoms in either trigonal prismatic (2H) or octahedral (1T) polyhedrons. With such a coordination configuration, only the edge X sites exhibit activity for hydrogen evolution reaction (HER). Here, a planar‐coordination transition metal chalcogenide, PdSe2 is reported, as an efficient electrocatalyst for the HER in an alkaline electrolyte. By reducing the spatial polyhedron coordination to planar polygon coordination, the M sites in PdSe2 can be efficiently activated to interact with the adsorptive intermediates. As a result, both Pd and Se atoms act as active sites for hydrogen evolution with neutral adsorption ability. With an overpotential of 138 mV at 10 mA cm−2, this work advances the exploration of planar‐coordination HER electrocatalysts. [ABSTRACT FROM AUTHOR]

Comprehensive characterization of traditional Chinese medicine prescriptions has long been a hurdle due to the chemical complexity and the lack of analytical tools. Mahuang decoction is a well‐known traditional Chinese medicine prescription widely used for sweating and relieving the exterior, relieving cough and asthma, but it was insufficiently chemically scrutinized. In this study, the chemical component information of Mahuang decoction was investigated by ultrahigh‐performance liquid chromatography tandem linear ion trap‐Orbitrap mass spectrometry. A new data processing tool, feature‐based molecular networking, was introduced for grouping and elucidating the compounds. In this way, 156 chemical components were identified or tentatively characterized, including alkaloids, triterpenoid saponins, flavanone‐O‐glycosides, flavone‐C‐glycosides, and procyanidins. Thus, this research provides a solid foundation for further development of Mahuang decoction, and the adopted method is expected to be applied to other traditional Chinese medicine prescriptions. [ABSTRACT FROM AUTHOR]

Significant efforts have been dedicated to boosting the electrocatalytic activity of Co9S8 for the oxygen evolution reaction (OER); however, with limited improvement in its intrinsic activity, which relies on careful band engineering. Fe possesses one less 3d electron and lower electronegativity than Co, suggesting a higher d‐band center when forming polyhedron with S anions. Here, to improve the intrinsic activity by elevating the d‐band center, the six‐coordinated octahedrons in Co9S8 are redesigned utilizing an Fe‐incorporated topochemical deintercalation method. Through substituting partial Co octahedrons by Fe octahedrons with higher d‐band, the overall d‐band center is regulated to achieve optimized adsorption and thus superior OER activity. With a reduction of 95 mV on the overpotential (at 10 mA cm−2), this work sheds lights on the design of OER catalysts through polyhedron engineering using topochemical deintercalation. [ABSTRACT FROM AUTHOR]

• MoS 2 /BiVO 4 heterojunction degrade RhB solution quickly without any addition agent. • Electrons in CB of MoS 2 and holes in VB of BiVO 4 promote redox ability. • MoS 2 /BiVO 4 heterojunction drive photocatalytic discoloration of RhB. Heterojunction photocatalysts can accelerate photo-excited electron-hole separation in the photocatalytic application. Herein, one BiVO 4 @MoS 2 core-shell heterojunction was synthesized via growing MoS 2 nanosheets on electrospinning-fabricated BiVO 4 nanorods by solvothermal technique. The MoS 2 /BiVO 4 heterojunction can completely degrade RhB solution within 20 min without any additional agent. According to the S-scheme heterojunction principle, the electron transfer process retains the powerful electrons in CB of MoS 2 and powerful holes in VB of BiVO 4 , and then promotes the excellent redox ability and strong driving force for photocatalytic discoloration of RhB. [ABSTRACT FROM AUTHOR]

Lamellar MoS 2 has attracted widespread attention as a potential electrocatalytic HER (Hydrogen evolution reaction) catalyst. However, it is difficult to further improve its catalytic activity due to two major drawbacks: the limited number of active sites and its poor conductivity. Here, we adopt a one-step method utilizing an ultrafast pulsed laser treatment to produce multiple decorations on lamellar MoS 2 , where nanocrystallization and amorphization of lamellar MoS 2 are achieved simultaneously, along with an additional characteristic of atomic steps. Due to this special microstructure, laser-treated MoS 2 exhibits excellent electrocatalytic performance with a low overpotential and a small Tafel slope (217 mV @ 10 mA cm−2 and 74.5 mV dec−1, respectively), which is superior to that of untreated lamellar MoS 2 (461 mV @ 10 mA cm−2 and 142.6 mV dec−1, respectively). The MoS 2 prepared in this way has a high catalytic activity and a high stability, which indicates potential for electrocatalysis applications. • We proposed a one-step method using ultrafast pulsed laser treatment to enhance the HER performance of lamellar MoS 2. • We prepared ultra-small MoS 2 nanoparticles, amorphization, and atomic steps in situ on lamellar MoS 2. • The performance of treated MoS 2 is far superior to that of MoS 2 before laser treatment. [ABSTRACT FROM AUTHOR]

As a rare plastic deformation mechanism, kinking has attracted substantial attention because of its additional softening effect on the matrix and its heterogeneous refinement on the original grains. However, the details of kinking deformation and the influence of crystal orientation on itself have not been sufficiently elucidated yet, thereby resulting in inadequate microstructure optimization associated with kinking. In this work, the kinking formation process in Fe-Cr-Al alloy during thermal compression deformation has been investigated by using quasi in-situ electron backscatter diffraction (EBSD). By employing the average Schmid factor (Average-SF) model, the influence of crystal orientation on kinking behavior is predicted accurately. The results suggest that the softening effect of kinking on the matrix can be attributed to the fact that the nucleation of pre kink bands (pre-KBs, misorientation <15°) leads to a pronounced reduction in geometrically necessary dislocations (GNDs) density within them. Besides, the ripening behavior of pre-KBs is closely associated with the variation of GNDs density and the overall slip activation capability of the matrix, and is essentially dependent on crystal orientation. The harder the crystal orientation, the smaller the Average-SF, the higher the increment rate of GNDs density, the larger the ripening rate pre-KBs. Under equivalent strain, orientations close to 〈111〉// compression direction (CD) have the highest probability of forming mature KBs with high angle grain boundaries (HAGBs, >15°), whereas KBs in those close to 〈001〉//CD almost always remain as pre-KBs with low angle grain boundaries (LAGBs). • The kinking formation of Fe-Cr-Al alloy is investigated by quasi in-situ EBSD. • The softening effect of kinking on the matrix is explained by EBSD and TEM. • The association of ripening of pre-KBs with GNDs density variation is revealed. • Kinking dependence on crystal orientation is predicted by Average-SF model. [ABSTRACT FROM AUTHOR]

Layered compounds play an important role in thermoelectric materials exploration, as their thermal and electrical conductivities could be affected by different layers. Herein, we have synthesized a new layered Ba 0.7 K 0.3 Cu 2 Se 2 phase with the ThCr 2 Si 2 structure through 30% K doping on the Ba sites in the pristine orthorhombic BaCu 2 Se 2 . The layered Ba 0.7 K 0.3 Cu 2 Se 2 exhibits intrinsically low lattice thermal conductivity due to its extremely short phonon mean free path. Ba 0.7 K 0.3 Cu 2 Se 2 also features high hole mobility and reasonable Seebeck coefficient at high doping levels. The enhancement of electrical conductivity is mainly ascribed to the increase of the hole concentration and the unchanged high hole mobility. As a result, the peak ZT of Ba 0.7 K 0.3 Cu 2 Se 2 reaches 0.32 at 800 K, which is of significance by comparing to its undoped BaCu 2 Se 2 counterpart. [ABSTRACT FROM AUTHOR]

This work provides insights into highly active alloys and sheds light on the utilization of electron-abundant metal atoms. Realizing Negatively Charged Metal Atoms through Controllable d-Electron Transfer in Ternary Ir1-xRhxSb Intermetallic Alloy for Hydrogen Evolution Reaction (Adv. Keywords: alloys; hydrogen evolution; water splitting EN alloys hydrogen evolution water splitting 1 1 1 07/11/22 20220707 NES 220707 B Water Splitting b In article number 2200855, Wenwu Zhong and co-workers prepare ternary intermetallic Ir SB 1- I x i sb Rh SB I x i sb Sb alloys with negatively charged metal sites, using the arc-melting method, to achieve advanced electrocatalytic activity for the hydrogen evolution reaction. [Extracted from the article]

[Display omitted] • Ni-Mo based nanorod arrays (NMNAs) were prepared by a one-step molten salt strategy. • This nanostructure favor the migration of bubbles and exposing more active sites. • NMNAs exhibit outstanding OER, HER, and overall water splitting activity. • The modulated electronic structures between Ni-Mo contribute to the high activity. The exploration of low-cost, high-efficient and robust bifunctional electrocatalysts for water splitting is urgently desired for developing clean hydrogen energy conversion technology. In this work, we present a facile and effective one-step molten salt synthesis tactics to prepare self-supported 1D Ni-Mo based mixed-phase polyionic compounds nanorod arrays (NMNAs). Due to the exposed more active sites of this nanostructure and accelerated charge transfer derived from modulated electronic structures between Ni-Mo, the as-fabricated NMNAs electrodes deliver remarkable bifunctional electrocatalytic water splitting performance, with overpotential values of 234.2 mV at 200 mA cm−2 and 191.2 mV at 100 mA cm−2 in 1 M KOH for OER and HER, respectively. Furthermore, the alkaline electrolyzer composed of NMNAs needs a low overall-water-splitting cell voltage of 1.423 V to drive a current density of 10 mA cm−2. This work will shed light on the preparation of other related self-supporting nanostructured bifunctional electrocatalysts with excellent performance. [ABSTRACT FROM AUTHOR]

Gan-Cao, or licorice, the dried roots and rhizomes of Glycyrrhiza uralensis , G.glabra , and G.inflata , has received considerable interest due to its extensive application in traditional Chinese medicine (TCM) prescriptions (60% approximately), clinical therapy, and as food additives world-wide. Chemical analysis is an important approach to understand the active pharmaceutical components in licorice and its prescriptions, as well as to develop novel methodologies for their quality assessment and control. This comprehensive review describes the advances in the chemical analysis, including sample preparation methods, qualitative and quantitative analysis and biological specimen analysis, based on 113 references for the recent years. Newly established methods are summarized, such as high performance thin layer chromatography (HPTLC), high performance liquid chromatography (HPLC), liquid chromatography tandem mass spectrometry (LC-MS), capillary electrophoresis (CE) and near infrared spectroscopy (NIR), which allows the identification, authentication, and simultaneous detection of multiple compounds in licorice with higher throughput and sensitivity. It is anticipated that this review could provide imperative information for improving the existing quality evaluation methods of licorice and afford scientific basis for further researches on the pharmacodynamic substances of licorice. Unlabelled Image [ABSTRACT FROM AUTHOR]

Oxygen Evolution Reaction: Elevating the d-Band Center of Six-Coordinated Octahedrons in Co9S8 through Fe-Incorporated Topochemical Deintercalation (Adv. Keywords: Co9S8; d-band center; octahedron; oxygen evolution reaction EN Co9S8 d-band center octahedron oxygen evolution reaction 1 1 1 02/06/21 20210204 NES 210204 In article number 2003023, Wenwu Zhong and co-workers re-design the six-coordinate octahedrons in Co SB 9 sb S SB 8 sb utilizing an Fe-incorporated topochemical deintercalation method to optimize the electrocatalytic activity for the oxygen evolution reaction (OER). This work sheds lights on the design of OER catalysts through polyhedron engineering using topochemical deintercalation. [Extracted from the article]

The new title compounds are synthesized by solid state reaction of stoichiometric mixtures of BaO, Co or Mn, Ag, and Se (alumina crucibles, 400 °C for 15 h and 850 °C for 24 h). [ABSTRACT FROM AUTHOR]

A series of compounds NaxFe2-yS2+z (0.8 ≤ x ≤ 1; 0.3 ≤ y ≤ 0.6; 0 ≤ z ≤ 0.1) is prepared by solid state reaction of the elements (800 °C, 30-48 h). [ABSTRACT FROM AUTHOR]

From a series of KxFe2Se2(NH3)y (x = 0.1-1.0) samples prepared by intercalation of K into β-FeSe in liquid NH3, K0.3Fe2Se2(NH3)0.47 and K0.6Fe2Se2(NH3)0.37 are obtained as pure phases of the 44 K and 30 K superconducting systems, respectively. [ABSTRACT FROM AUTHOR]