摘要：The optoelectronic properties of atomically thin transition metal dichalcogenides(TMDs)are largely influenced by defect populations(DPs).In this work,we fabricate WSmonolayers with different DPs by varying the fabrication methods and further reveal their distinct exciton-exciton ***-state photoluminescence(PL)experiments show that the monolayer with the lowest DP shows optimal PL intensity at low excitation power;however,it is overtaken and significantly surpassed by monolayers with higher DPs at high excitation ***-power-dependent experiments demonstrate that these monolayers exhibit distinct PL saturation behaviors with the threshold power differing by four orders of *** with in situ PL imaging and time-resolved PL experiments,we attribute such PL evolution discrepancies to the different DPs within these monolayers,which largely influence the exciton diffusion behavior and subsequently bring about distinct nonradiative exciton-exciton annihilations(EEAs).Valley polarization experiments are further employed to re-examine the DPs of these *** work reveals the distinct PL behaviors and underlying exciton dynamics in TMD monolayers with different DPs,which can largely facilitate the engineering of relevant high-performance devices for practical applications.

摘要：Nanoporous metals show promising performances in electrochemical *** this paper,we report a self-supporting bimetallic porous heterogeneous indium/copper structure synthesized with a eutectic gallium-indium(EGaIn)material on a copper *** nanoporous copper-indium heterostructure catalyst exhibits excellent performance in the reduction of carbon dioxide to *** ratio of H_(2)/CO is tunable from 0.47 to 2.0 by changing working *** catalyst is highly stable,showing 96%maintenance of the current density after a 70-h continuous *** functional theory calculations reveal that the indium/copper interface induces charge redistribution within the copper surface,leading to the formation of two distinct active sites,namely,Cu^(δ)and Cu0,and enabling a high-performance generation of CO and H_(2).This work provides a new strategy for obtaining self-supporting nanoporous metal electrode catalysts.

摘要：Photocatalytic conversion of“greenhouse gas”CO2is considered to be one of the most effective ways to alleviate current energy and environmental problems without additional energy consumption and pollutant *** performance of many traditional semiconductor photocatalysts is not efficient enough to satisfy the requirements of practical applications because of their limited specific surface area and low CO2adsorption ***,the exploration of photocatalysts with high CO2uptake is significant in the field of *** the porous materials appeared to be a kind of superior candidate for enriching the CO2molecules on the surface of photocatalysts for catalytic *** paper first summarizes the advances in the development of nanoporous adsorbents for *** main classes of porous materials are considered:inorganic porous materials,metal organic frameworks,and microporous organic *** on systematic research on CO2uptake,we then highlight the recent progress in these porous‐material‐based photocatalysts for *** from the improved CO2uptake capacity,the porous‐material‐based photocatalysts exhibited remarkably enhanced efficiency in the reduction of CO2to chemical fuels,such as CO,CH4,and *** on reported recent achievements,we predict a trend of development in multifunctional materials with both high adsorption capability and photocatalytic performance for CO2utilization.

摘要：Photonic synaptic transistors are promising neuromorphic computing systems that are expected to circumvent the intrinsic limitations of von Neumann-based *** design and construction of photonic synaptic transistors with a facile fabrication process and highefficiency information processing ability are highly desired,while it remains a tremendous ***,a new approach based on spin coating of a blend of CsPbBr_(3) perovskite quantum dot(QD)and PDVT-10 conjugated polymer is reported for the fabrication of photonic synaptic *** combination of flat surface,outstanding optical absorption,and remarkable charge transporting performance contributes to high-efficiency photon-to-electron conversion for such perovskite-based ***-performance photonic synaptic transistors are thus fabricated with essential synaptic functionalities,including excitatory postsynaptic current(EPSC),paired-pulse facilitation(PPF),and long-term *** utilizing the photonic potentiation and electrical depression features,perovskite-based photonic synaptic transistors are also explored for neuromorphic computing simulations,showing high pattern recognition accuracy of up to 89.98%,which is one of the best values reported so far for synaptic transistors used in pattern *** work provides an effective and convenient pathway for fabricating perovskite-based neuromorphic systems with high pattern recognition accuracy.

摘要：In the context of the current serious problems related to energy demand and climate change,substantial progress has been made in developing a sustainable energy *** hydrogen-water conversion is an ideal energy system that can produce fuels via sustainable,fossil-free ***,the energy conversion efficiency of two functioning technologies in this energy system—namely,water electrolysis and the fuel cell—still has great scope for *** review analyzes the energy dissipation of water electrolysis and the fuel cell in the hydrogen-water energy system and discusses the key barriers in the hydrogen-and oxygen-involving reactions that occur on the catalyst *** means of the scaling relations between reactive intermediates and their apparent catalytic performance,this article summarizes the frameworks of the catalytic activity trends,providing insights into the design of highly active electrocatalysts for the involved reactions.A series of structural engineering methodologies(including nano architecture,facet engineering,polymorph engineering,amorphization,defect engineering,element doping,interface engineering,and alloying)and their applications based on catalytic performance are then introduced,w让h an emphasis on the rational guidance from previous theoretical and experimental *** key scientific problems in the electrochemical hydrogen-water conversion system are outlined,and future directions are proposed for developing advanced catalysts for technologies with high energy-conversion efficiency.

摘要：The pump performance parameters,such as pump pressure,plunger friction and pump valve resistance,are fundamental parameters of optimal design of pump efficiency and sucker rod pumping system (SRPS).In this paper,considering the characteristic of geometrical nonlinear and rheology property of multiphase fluid,the pump performance parameters are ***,a dynamics model of annular fluid flow is *** the detail,a partial differential equation of annular fluid is established and a computing model of fluid pressure gradient is ***,the simulation models of plunger friction and hydraulic resistance of pump valve are ***,a novel simulation method of fluid pressure in annular space is proposed with software *** order to check up the correction of models proposed in this paper,the comparison curves of experiment and simulation results are *** on above model,the whole simulation model of plunger pump is simulated with Visual Basic *** results show that the fluid friction of pump plunger and instantaneous resistance of pump valve are *** impact factors of pump performance parameters are analyzed,and their characteristic curves are given,which can help to optimize the pump motion parameters and pump structural.

摘要：The one-pot assembly reaction of a trilacunary,lone-pair-containing[B-α-SbW9O33]*** with Co2+ions in an aqueous medium led to the isolation of a novel{SbO3(H2O)3}bridging,dicobalt-substituted,sandwich-type tungstoantimonate{Co2Sb2(H2O)10[B-β-SbW9O33]2}^4–(1a).This compound was structurally characterized in the solid state by single-crystal X-ray diffraction,elemental analyses,thermogravimetric analysis,and IR *** most remarkable feature was that 1a comprises two trilacunary[B-β-SbW9O33]9^-fragments trapping a novel,centrally symmetric,rhomb-like{Co2Sb2}belt with 10 terminal water *** combined with the photosensitizer[Ru(bpy)3]^2+and the sacrificial electron acceptor S2O82.,1a exhibited efficient catalytic activity for water oxidation with a remarkable turnover number(TON)of 193,initial turnover frequency(TOFinitial)of 5.3 s^-1,O2 yield of 30.8%,and quantum yield(ФQY)of 36.2%under light-driven conditions.

摘要：Herein,we report a three-dimensional porous TiO_(2)/Fe_(2)TiO_(5)/Fe_(2)O_(3)(TFF)inverse opal through in situ thermal solid reactions for photoelectrochemical water *** Fe_(2)TiO_(5) interfacial layer within TFF acting as a bridge to tightly connect to TiO_(2) and Fe_(2)O_(3) reduces the interfacial charge transfer resistance,and suppresses the bulk carrier *** optimized TFF displays a remarkable photocurrent density of 0.54mAcm^(-2) at 1.23V *** hydrogen electrode(RHE),which is 25 times higher than that of TiO_(2)/Fe_(2)O_(3)(TF)inverse opal(0.02mAcm^(-2) at 1.23V ***).The charge transfer rate in TFF inverse opal is 2-8 times higher than that of TF in the potential range of 0.7-1.5V *** effects of the Fe_(2)TiO_(5) interfacial layer are further revealed by X-ray absorption spectroscopy and intensity-modulated photocurrent *** work offers an interfacial engineering protocol to improve charge separation and transfer for efficient solar water splitting.

摘要：With the increasing concerns to energy shortage and environmental problems in modern society,the development of cheap,clean,and sustainable energy alternatives has been attracting tremendous attention *** various strategies of renewable energy exploration,solar-driven water splitting into its compositional elements H2 and O2 is an ideal approach to convert and store renewable solar energy into chemical *** recent few decades,as an emerging new type of catalysts,polyoxometalates(POMs)have been widely utilized for water splitting due to their versatile synthetic methodology and highly tunable physicochemical and photochemical *** critical review addresses the research advances of light-driven hydrogen evolution using polyoxometalate-based catalysts,including plenary POMs,transition-metal-substituted POMs,POM@MOF composites,and POM-semiconductor hybrids,under UV,near UV and visible light *** addition,the catalytic mechanism for each reaction system has been thoroughly discussed and ***,a comprehensive outlook of this research area is also prospected.

摘要：Nanowires with anisotropic morphologies have been applied in various scientific and technological *** is also widely employed to fabricate nanowires into high-dimensional superstructures(arrays,networks etc.)to overcome the shortcomings of low-dimensional ***,typical strategies for constructing these superstructures are restricted to complicated and harsh synthetic conditions,not to mention unique 3D structures with advanced properties beyond common ***,we report an unusual network ofα-MnO_(2)nanowires with structure-induced hydrophilicity and *** the network,the nanowires are interconnected from all directions by nodes,and the 3D network structure is formed from the endless connection of nodes in a node-by-node *** unique network structure brings about high hydrophilicity and conductivity,both of which are positive factors for an efficient ***,the α-MnO_(2) network was tested for electrocatalytic water oxidation and showed significantly enhanced activity compared with isolatedα-MnO_(2)nanowires and 3Dα-MnO_(2)*** study not only provides a synthetic route toward an advanced network structure but also a new idea for the design of materials for electrochemistry with both efficient mass diffusion and charge transfer.