Chromosome-level genome assembly of Salvia miltiorrhiza with orange roots uncovers the role of Sm2OGD3 in catalyzing 15,16-dehydrogenation of tanshinones

Salvia miltiorrhiza is well known for its clinical practice in treating heart and cardiovascular diseases.Its roots,used for traditional Chinese medicine materials,are usually brick-red due to accumulation of red pigments,such as tanshinone IIA and tanshinone I.Here we report a S.miltiorrhiza line(shh)with orange roots.Compared with the red roots of normal S.miltiorrhiza plants,the contents of tanshinones with a single bond at C-15,16 were increased,whereas those with a double bond at C-15,16 were significantly decreased in shh.We assembled a high-quality chromosome-level genome of shh.Phylogenomic analysis showed that the relationship between two S.miltiorrhiza lines with red roots was closer than the relationship with shh.It indicates that shh could not be the mutant of an extant S.miltiorrhiza line with red roots.Comparative genomic and transcriptomic analyses showed that a 1.0 kb DNA fragment was deleted in shh Sm2OGD3m.Complementation assay showed that overexpression of intact Sm2OGD3 in shh hairy roots recovered furan D-ring tanshinone accumulation.Consistently,in vitro protein assay showed that Sm2OGD3 catalyzed the conversion of cyptotanshinone,15,16-dihydrotanshinone I and 1,2,15,16-tetrahydrotanshinone I into tanshinone IIA,tanshinone I and 1,2-dihydrotanshinone I,respectively.Thus,Sm2OGD3 functions as tanshinone 15,16-dehydrogenase and is a key enzyme in tanshinone biosynthesis.The results provide novel insights into the metabolic network of medicinally important tanshinone compounds.

Metal-organic decomposition growth of thin film metastable perovskite nickelates with kinetically improved quantum transitions

The multiple quantum transitions within d-band correlation oxides such as rare-earth nickelates(RENiO_(3))triggered by critical temperatures and/or hydrogenation opened up a new paradigm for correlated electronics applications,e.g.ocean electric field sensor,bio-sensor,and neuron synapse logical devices.Nevertheless,these applications are obstructed by the present ineffectiveness in the thin film growth of the metastable RENiO_(3)with flexibly adjustable rare-earth compositions and electronic structures.Herein,we demonstrate a metal-organic decompositions(MOD)approach that can effectively grow metastable RENiO_(3)covering a large variety of the rare-earth composition without introducing any vacuum process.Unlike the previous chemical growths for RENiO_(3)relying on strict interfacial coherency that limit the film thickness,the MOD growth using reactive isooctanoate percussors is tolerant to lattice defects and therefore achieves comparable film thickness to vacuum depositions.Further indicated by positron annihilation spectroscopy,the RENiO_(3)grown by MOD exhibit large amount of lattice defects that improves their hydrogen incorporation amount and electron transfers,as demonstrated by the resonant nuclear reaction analysis and near edge X-ray absorption fine structure analysis.This effectively enlarges the magnitude in the resistance regulations in particular for RENiO_(3)with lighter RE,shedding a light on the extrinsic regulation of the hydrogen induced quantum transitions for correlated oxides semiconductors kinetically via defect engineering.

Pressure-Induced Superconductivity in the Charge-Density-Wave Compound LaTe_(2-x)Sb_(x)(x=0 and 0.4)

Magnetic CeTe_(2)achieving superconductivity under external pressure has received considerable attention.The intermingling of 4f and 5d electrons from Ce raised the speculation of an unconventional pairing mechanism arising from magnetic fluctuations.Here,we address this speculation using a nonmagnetic 4f-electron-free LaTe_(2)as an example.No structural phase transition can be observed up to 35 GPa in the in situ synchrotron diffraction patterns.Subsequent high-pressure electrical measurements show that LaTe_(2)exhibits superconductivity at20 Gpa with its T_(c)(4.5 K)being two times higher than its Ce-counterpart.Detailed theoretical calculations reveal that charge transfer from the 4p orbitals of the planar square Te-Te network to the 5d orbitals of La is responsible for the emergence of superconductivity in LaTe_(2),as confirmed by Hall experiments.Furthermore,we study the modulation of q_(CDW)by Sb substitution and find a record high T_(c)^(onset)~6.5 K in LaTe_(1.6)Sb_(0.4).Our work provides an informative clue to comprehend the role of 5d-4p hybridization in the relationship between charge density wave(CDW)and superconductivity in these RETe_(2)(RE=rare-earth elements)compounds.

Electron-Deficient Zn-N_(6) Configuration Enabling Polymeric Carbon Nitride for Visible-Light Photocatalytic Overall Water Splitting

Despite of suitable band structures for harvesting solar light and driving water redox reactions,polymeric carbon nitride(PCN)has suffered from poor charge transfer ability and sluggish surface reaction kinetics,which limit its photocatalytic activity for water splitting.Herein,atomically dispersed Zn-coordinated three-dimensional(3D)sponge-like PCN(Zn-PCN)is synthesized through a novel intermediate coordination strategy.Advanced characterizations and theoretical calculations well evidence that Zn single atoms are coordinated and stabilized on PCN in the form of Zn-N_(6) configura-tion featured with an electron-deficient state.Such an electronic configuration has been demonstrated contributive to promoted electron excitation,accelerated charge separation and transfer as well as reduced water redox barriers.Further benefited from the abundant surface active sites derived from the 3D porous structure,Zn-PCN realizes visible-light photocatalysis for overall water splitting with H_(2) and O_(2) simultaneously evolved at a stoichiometric ratio of 2:1.This work brings new insights into the design of novel single-atom photocatalysts by deepening the understanding of electronic configurations and reactive sites favorable to excellent photocatalysis for water splitting and related solar energy conversion reactions.

Discovery of Two Families of VSb-Based Compounds with V-Kagome Lattice

We report the structure and physical properties of two newly discovered compounds AV_(8)Sb_(12)and AV_(6)Sb_(6)(A=Cs,Rb),which have C_(2)(space group:Cmmm)and C_(3)(space group:R3 m)symmetry,respectively.The basic Vkagome unit appears in both compounds,but stacking differently.AV_(2)Sb_(2) layer is sandwiched between two V_(3)Sb_(5)layers in AV_(8)Sb_(12),altering the V-kagome lattice and lowering the symmetry of kagome layer from hexagonal to orthorhombic.In AV_(6)Sb_(6),the building block is a more complex slab made up of two half-V_(3)Sb_(5)layers that are intercalated by Cs cations along the c-axis.Transport property measurements demonstrate that both compounds are nonmagnetic metals,with carrier concentrations at around 10^(21)cm^(-3).No superconductivity has been observed in CsV_(8)Sb_(12)above 0.3 K under in situ pressure up to 46 GPa.Compared to CSV_(3)Sb_(5),theoretical calculations and angle-resolved photoemission spectroscopy reveal a quasi-two-dimensional electronic structure in CsV_(8)Sb_(12)with C_(2)symmetry and no van Hove singularities near the Fermi level.Our findings will stimulate more research into V-based kagome quantum materials.

Zirconium Aided Epitaxial Growth of InxSey on InP(111) Substrates Cheng

Layered material indium selenide(InxSey)is a promising candidate for building next-generation electronic and photonic devices.We report a zirconium aided MBE growth of this van der Waals material.When co-depositing zirconium and selenium onto an indium phosphide substrate with a substrate temperature of 400℃at a constant zirconium flux rate of 0.01 ML/min,the polymorphic Inx Sey layer emerges on top of the insulating ZrSe2 layer.Different archetypes,such as InSe,α-In2Se3 and α-In2Se3,are found in the InxSey layers.A negative magnetoresistance of 40%at 2 K under 9 T magnetic field is observed.Such an InxSeyZrSe2 heterostructure with good lattice-matching may serve as a candidate for device applications.

La_(0.67)Sr_(0.33)MnO_(3)薄膜相图的轨道弹性调控

过渡金属氧化物具有丰富的功能性,但其错综复杂的内部自由度对相图绘制和结构设计提出了挑战.本文中,我们引入了描述相图物理起源的轨道能级序(ELO),并通过对La_(0.67)Sr_(0.33)MnO_(3)(LSMO)氧化物的研究证明了其在相图预测中的有效性.结合DFT计算和实验,我们构建了氧含量和应变关联的LSMO相图,结果表明LSMO结构稳定性与ELO密切相关.据此发现了一种由ELO演化而产生的四倍氧有序相.最后,我们提出了描述轨道分裂程度的轨道弹性定律,阐明了ELO演化的起源,助力功能氧化物的设计.这项研究拓宽了材料科学领域的性能调控手段,并为从轨道角度预测相图提供了思路.

Interdigitated terahertz metamaterial sensors:design with the dielectric perturbation theory

Designing terahertz sensors for highly sensitive detection of nanoscale thin films and a few biomolecules poses a substantial challenge but is crucial for unlocking their full potential in scientific research and advanced applications.This work presents a strategy for optimizing metamaterial sensors in detecting small quantities of dielectric materi-als.The amount of frequency shift depends on intrinsic properties(electric field distribution,Q-factor,and mode volume)of the bare cavity as well as the overlap volume of its high-electric-field zone(s)and the analyte.Guided by the simplified dielectric perturbation theory,interdigitated electric split-ring resonators(ID-eSRRs)are devised to significantly enhance the detection sensitivity compared with eSRRs without interdigitated fingers.ID-eSRR’s fin-gers redistribute the electric field,creating strongly localized enhancements,which boost analyte interaction.The periodic change of the inherent antiphase electric field reduces radiation loss,leading to a higher Q-factor.Experiments with ID-eSRR sensors operating at around 300 GHz demonstrate a remarkable 33.5 GHz frequency shift upon depositing a 150 nm SiO_(2)layer as an analyte simulant,with a figure of merit improvement of over 50 times compared with structures without interdigitated fingers.This rational design offers a promising avenue for highly sensitive detection of thin films and trace biomolecules.

Frequency regulation in alternation-current transports across metal to insulator transitions of thin film correlated perovskite nickelates

Although the metal to insulator transition(MIT)observed in d-band correlated metal oxides enables promising applications(e.g.,correlated logical devices and Mottronic devices),its present recognition is mainly limited on the direct current(DC)electrical transports.Up to date,the MIT from the perspective of alternation current(AC)transport and its potential electronic applications remains yet unclear.Herein,we demonstrate the frequency(f_(AC))dependence in the impedance(Z=Z’+iZ″)of typical MIT materials,such as thin film rare-earth nickelates(Re NiO_(3)),across the critical MIT temperature(T_(MIT)).Apart from the abrupt change in the impedance modulus(|Z|)across the critical temperature(T_(MIT))similar to the DC transport,the MIT also triggers non-continuous variation in the impedance phase(θ),and this enables the f_(AC)-regulations in the Z’-T tendencies(Z’=|Z|cosθ).At the critical f_(AC) range(e.g.,104-106 Hz),the con-versing variations in|Z|-T and cosθ-T across T_(MIT) result in non-monotonic delta-shape Z’-T tendency in Sm_(x) Nd_(1-x) NiO_(3),the full width half maximum of which is effectively narrowed compared to the situation with the absence of MIT.Further imparting lower or higher f_(AC) elevate the domination in|Z|-T and cosθ-T,respectively,but also enables abrupt Z’-T tendencies across T_(MIT) showing negative temperature coefficient of resistance(NTCR)or positive temperature coefficient of resistance(PTCR).By introducing f_(AC) as a new freedom,the MIT behavior can be more comprehensively regulated electronically,and this extends the vision in exploring the new electronic applications based on the correlated MIT materials from the AC perspective.

Dual-bionic regenerative microenvironment for peripheral nerve repair

Autologous nerve grafting serves is considered the gold standard treatment for peripheral nerve defects;however,limited availability and donor area destruction restrict its widespread clinical application.Although the performance of allogeneic decellularized nerve implants has been explored,challenges such as insufficient human donors have been a major drawback to its clinical use.Tissue-engineered neural regeneration materials have been developed over the years,and researchers have explored strategies to mimic the peripheral neural microenvironment during the design of nerve catheter grafts,namely the extracellular matrix(ECM),which includes mechanical,physical,and biochemical signals that support nerve regeneration.In this study,polycaprolactone/silk fibroin(PCL/SF)-aligned electrospun material was modified with ECM derived from human umbilical cord mesenchymal stem cells(hUMSCs),and a dual-bionic nerve regeneration material was successfully fabricated.The results indicated that the developed biomimetic material had excellent biological properties,providing sufficient anchorage for Schwann cells and subsequent axon regeneration and angiogenesis processes.Moreover,the dual-bionic material exerted a similar effect to that of autologous nerve transplantation in bridging peripheral nerve defects in rats.In conclusion,this study provides a new concept for designing neural regeneration materials,and the prepared dual-bionic repair materials have excellent auxiliary regenerative ability and further preclinical testing is warranted to evaluate its clinical application potential.

2D-to-3D buckling transformability enabled reconfigurable metamaterials for tunable chirality and focusing effect

Recently,multifarious deformation approaches in nature have promoted dynamic manipulation for electromagnetic(EM)waves in metamaterials,and those representative strategies are mainly focused on the modulation of spectral parameters.Several works have also achieved tunable phase-gradient meta-devices.Here,to broaden the modulation freedom of mechanical deformation,we initially propose two reconfigurable metamaterials consisting of mirrored S-shaped meta-atoms selectively bonded on biaxially pre-stretched substrates.Planar meta-atoms with spin-insensitive transmittance are buckled into 3D morphologies to break residual symmetries by releasing the stress and to facilitate spin-dependent transmittance under circularly polarized incidence.Owing to the geometric anisotropy of S-shaped meta-atoms along the x and y axes,3D chiral meta-atoms exhibit discriminate circularly cross-polarized transmittance under opposite spins.The underlying physical mechanism reveals that EM resonance originates from the excitation of electric dipoles and magnetic dipoles,and their cross coupling finally triggers the chiral effects of 3D meta-atoms.By introducing the gradient-phase design that keeps unchanged under various strains,two types of meta-atoms with specified orientations are interleaved to design a double-foci metalens,and its 2D-to-3D morphology transformation shortens the focusing length and facilitates the intensity change of two foci.Our approach in designing reconfigurable EM metamaterials with 2D-to-3D buckling transformability can be further extended toward terahertz even optical wavebands,and it may assist with deriving more applicable multi-functionalities in the aspects of imaging,sensing,and holograms.

Boosting Li-ion storage in Li2MnO_(3) by unequal-valent Ti4+-substitution and interlayer Li vacancies building

Lithium rich layered oxide(LRLO) has been considered as one of the promising cathodes for lithium-ion batteries(LIBs). The high voltage and large capacity of LRLO depend on Li2MnO_(3)phase. To ameliorate the electrochemical performance of Li2MnO_(3), also written as Li(Li1/3Mn2/3)O_(2), we propose a strategy to substitute Mn4+and Li+in Mn/Li transition metal layer with Ti4+, which can stabilize the structure of Li2MnO_(3)by inhibiting the excessive oxidation of O_(2)-above 4.5 V. More significantly, the unequal-valent substitution brings about the emergence of interlayer Li vacancies, which can promote the Li-ion diffusion based on the enlarged interlayer and increase the capacity by activating the Mn3+/4+redox. We designed Li0.7[Li1/3Mn2/3]0.7Ti0.3O_(2)with high interlayer Li vacancies, which presents a high capacity(290 m Ah/g at 10 m A/g) and stable cycling performance(84% over 60 cycles at 50 m A/g). We predict that this strategy will be helpful to further improve the electrochemical performance of LRLOs.

Domain Wall Evolution in Hf_(0.5)Zr_(0.5)O_(2)Ferroelectrics under Field-Cycling Behavior

HfO_(2)-based ferroelectrics have evoked considerable interest owing to the complementary metal-oxide semiconductor compatibility and robust ferroelectricity down to a few unit cells.However,the unique wake-up effect of HfO_(2)-based ferroelectric films severely restricts the improvement of their performance.In particular,the domain structure is an important characteristic of ferroelectric materials,which still has not been well understood in HfO_(2)-based ferroelectrics.In this work,a Hf_(0.5)Zr_(0.5)O_(2) ferroelectric thin film is grown on a typical Si substrate buffered with TiN electrode.The 90°domains of the Pca21 ferroelectric phase with head-to-tail and tail-to-tail structures can be observed by Cs-corrected scanning transmission electron microscope under their pristine condition.After waking up,the 180°domain is displayed in the ferroelectric phase.The remarkable differences in domain walls for 90°and 180°domains are characterized by qualitatively mapping the polarization distributions at the atomic scale.The domain wall changes from the[101]of the Hf_(0.5)Zr_(0.5)O_(2) film to the[001]of the Hf_(0.5)Zr_(0.5)O_(2) film.This result provides fundamental information for understanding the domain structure of HfO_(2)-based ferroelectrics.

A new artificial photosynthetic system coupling photovoltaic electrocatalysis with solar heating catalysis

In this work,we present a novel artificial photosynthetic paradigm with square meter(m^(2))level scalable production by integrating photovoltaic electrolytic water splitting device and solar heating CO_(2)hydrogenation device,successfully achieving the synergy of 1 sun driven 19.4%solar to chemical energy efficiency(STC)for CO production(2.7 times higher than that of large-sized artificial photosynthetic systems)with a low cost(equivalent to 1/7 of reported artificial photosynthetic systems).Furthermore,the outdoor artificial photosynthetic demonstration with 1.268 m^(2)of scale exhibits the CO generation amount of 258.4 L per day,the STC of~15.5%for CO production in winter,which could recover the cost within 833 sunny days of operation by selling CO.

Highly active zigzag-like Pt-Zn alloy nanowires with high-index facets for alcohol electrooxidation

The development of highly efficient Pt-based alloy nanocatalysts is important but remains challenging for fuel cells commercialization.Here,a new class of zigzag-like platinum-zinc (Pt-Zn) alloy nanowires (NWs) with rough surface and controllable composition is reported.The merits of anisotropic one-dimensional nanostructure,stable high-index facets and coordinatively unsaturated Pt sites endow the composition-optimal Pt94Zn6 NWs with a mass activity of 7.2 and 6.2 times higher than that of commercial Pt black catalysts toward methanol/ethanol oxidation,respectively.Alloying-induced d-band electron modulation and lattice strain effects weaken the adsorption strength of poisoning species,which originally enhances the catalytic activity of Pt-Zn NWs.This study provides a new perspective of Pt-Zn electrocatalysts with intrinsic mechanism for enhanced catalytic performance.

Boosting photocatalytic hydrogen production by creating isotype heterojunctions and single-atom active sites in highly-crystallized carbon nitride

Carbon nitride-based photocatalysts hold an enormous potential in producing hydrogen.A strategy to simultaneously create isotype heterojunctions and active sites in highly-crystallized carbon nitride is anticipated to significantly boost the photocatalytic activity,but is yet to be realized.Herein,we find that cobalt salt added in the ionothermal synthesis can promote the phase transition of heptazine-based crystalline carbon nitride(CCN)to triazine-based poly(triazine imide)(PTI),rendering the creation of singleatom cobalt coordinated isotype CCN/PTI heterojunction.Co-CCN/PTI exhibits an appreciable apparent quantum yield of 20.88%at 425 nm for photocatalytic hydrogen production with a rate achieving3538μmol h^(-1)g^(-1)(λ>420 nm),which is 4.8 times that of CCN and 27.6 times that of PTI.The high photocatalytic activity is attributed to the Type II isotype highly-crystallized CCN/PTI heterojunction for promoting charge carrier migration,and the single-atom Co sites for accelerating surface oxidation reaction.

Semi-chemical interaction between graphitic carbon nitride and Pt for boosting photocatalytic hydrogen evolution

Owing to the exorbitant overpotential and serious carrier recombination of graphitic carbon nitride(gC_(3)N_(4)),noble metal(NM)is usually served as the H_(2)evolution co-catalyst.Although the NM(such as Pt)nanoparticles can reduce the H_(2)evolution overpotential,the weak van der Waals interaction between Pt and g-C_(3)N_(4)makes against the charge transfer.Herein,the solvothermal method is developed to achieve semi-chemical interaction between Pt and g-C_(3)N_(4)nanotube(Pt-CNNT)for fast charge transfer.Moreover,the generated in-plane homojunction of CNNT can accelerate charge separation and restrain recombination.Meanwhile,the metallic Pt is an excellent H_(2)evolution co-catalyst.Photo/electrochemical tests verify that the semi-chemical interaction can improve photogenerated charge separation and transferability of CNNT.As a result,the photocatalytic H_(2)evolution turnover frequency(TOF)of Pt-CNNT under visible light irradiation reaches up to 918 h^(-1),which is one of the highest in the g-C_(3)N_(4)-based photocatalysts.This work provides a new idea to improve the charge transfer for efficient photocatalytic H_(2)evolution.

Superconductivity above 28K in single unit cell FeSe ?lms interfaced with GaO_(2-δ) layer on NdGaO_3(110)

The discovery of high temperature superconductivity in single unit cell(UC)FeSe on TiO2-δterminated perovskite SrTiO3(001)substrates[1]has attracted intensive attention on searching for new superconducting systems with engineered interfaces as well as understanding the mechanism of interface high temperature superconductivity.

Photocatalytic and electrochemical degradation of methylene blue by titanium dioxide

A photoanode structure for dye-sensitized solar cells has been applied into the photocatalytic/electrochemical cooperative degradation of methylene blue solutions.The low eutectic point of titanium dioxide(TiO2)with a fluorine-doped tin dioxide(FTO)conductive layer results in a high reactivity of TiO2for the photocatalytic process as well as a good electron transfer for the electrochemical process.The porous TiO2layer maintains a large surface area for the degradations.Through the combinational process,the degradation velocity was improved by*36%,compared to a pure photocatalytic process.

Erratum to:Highly active zigzag-like Pt-Zn alloy nanowires with high-index facets for alcohol electrooxidation

The article Highly active zigzag-like Pt-Zn alloy nanowires with high-index facets for alcohol electrooxidation, written by Xiaoqiang Cui and Weitao Zheng, was erroneously originally published electronically on the publisher’s internet portal (currently SpringerLink) on 6 April 2019 with incomplete Electronic Supplementary Material (ESM), which should contain 16 figures and 3 tables. You will find the complete supplementary material file online linked to this publisher’s erratum.