摘要：近年来,光催化产氢与有机物氧化的偶联反应备受关注,如何设计高效双功能光催化剂实现偶联反应成为研究重点.在众多光催化剂中,ZnIn_(2)S_(4)以其优异的可见光吸收能力、本征的极化电场以及较强的氧化还原能力成为双功能催化剂的热点备选材料.然而,电子空穴分离效率低以及光生电子空穴复合率高的问题限制了ZnIn_(2)S_(4)光电转化效率的进一步提高.针对这一问题,我们采用了具有较高导电性和独特结构的金属相1T-MoS_(2)作为助催化剂与花状ZnIn_(2)S_(4)复合形成“海胆状”的1T-MoS_(2)/ZnIn_(2)S_(4)欧姆结复合材料.理论计算结合XPS数据揭示了欧姆结与内建电场的形成,一系列光谱表征表明由欧姆结所形成的强内建电场促进了ZnIn_(2)S_(4)体内光生电子快速向1T-MoS_(2)转移,同时活性测试与EPR表征证明了苯甲醇的氧化反应可以作为光生空穴的有效捕获剂.最终,1T-MoS_(2)/ZnIn_(2)S_(4)复合光催化剂实现了4.6倍光催化性能的提高,420 nm波长下表光量子效率达6.75%.本项工作通过精确调节电荷转移机制,实现了ZnIn_(2)S_(4)双功能催化剂光电效率的进一步提高,为光催化剂载流子调控设计提供了新思路.

摘要：非化学计量的氧化硅(SiO_(x),0<x<2)是一种很有前途的锂电池负极材料.然而,它的本征电导率低,体积膨胀明显.特别是,由于连续的电解液消耗,很难形成稳定的固体电解质界面.本工作将空心氧化硅微球包裹在钴碳(Co-C)骨架及其衍生的氮掺杂碳纳米管网络(N-CNTs)中.这种设计解决了电解液消耗和SEI层重复形成的问题,并实现了快速动力学.此外,所制备材料的柔性碳纳米管和坚固金属-碳框架提供力学支撑,可以适应SiO_(x)体积变化.h-SiO_(x)@Co@N-CNTs作为锂离子电池负极材料,具有优异的循环稳定性和高倍率性能.以0.2 A g^(-1)的电流密度循环370次,容量为701 mAh g^(-1),容量保持率为100%.另外,在1.0 A g^(-1)电流密度下循环500圈,容量没有衰减.结果表明,所合成的锂离子电池结构具有一定的优越性,对材料的优化也有一定的启发作用.

摘要：利用太阳能将CO_(2)光转化为化学燃料是前沿研究的热点.当前,科研的重点在于开发和优化各类光催化材料的性能.异质结构不仅用于增强无机半导体催化剂的活性,而且用于金属-有机框架(MOFs)光催化剂的构建.随着异质结技术的不断进步,新的相结概念应运而生.尽管关于无机半导体中的相结研究已取得一定进展,但是MOFs相结结构的探索尚处于起步阶段.本文中,我们成功设计并构建了一种具有卓越光催化CO_(2)还原性能的MOFs相结杂化材料.这种材料由具有高度连接性的卟啉配体(TCPP-Ni)与Zr6团簇紧密结合而成,在溶剂热反应条件下,PCN-222-Ni能够快速且均匀地成核.通过精准调控调节剂的用量,我们实现了同分异构体PCN-224-Ni在类似条件下较慢的晶体形成过程.最终制得的P@P杂化材料展现出高表面积、多孔性和卓越的结晶度.由于PCN-222-Ni和PCN-224-Ni之间的带隙匹配,光生载流子的分离和迁移得以促进,从而使P@P杂化材料展现出卓越的光还原CO_(2)性能.这一重大突破不仅标志着MOFs相结结构研究的重大进展,还拓宽了MOFs相结在CO_(2)光转化领域的应用前景.

摘要：An S-scheme heterojunction photocatalyst is capable of boosting photogenerated carrier separation and transfer,thus maintaining high photooxidation and photoredox ***,a 0D Ag_(3)PO_(4) nanoparticles(NPs)/1D TiO_(2) nanofibers(NFs)S-scheme heterojunction with intimate interfacial contact was designed via the the hydro-thermal *** from the abundant hydroxyl groups and size confinement effect of TiO_(2) NFs,the average diameter of the Ag_(3)PO_(4) nanoparticles decreased from 100 to 22 nm,which favored the construction of a 0D/1D geometry *** multifunctional Ag_(3)PO_(4)/TiO_(2) sample exhibited excellent photocatalytic activity and stability in photocatalytic oxygen production(726μmol/g/h)and photocatalytic degradation of various organic contaminants such as rhodamine B(100%),phenol(60%)and tetracycline hydrochloride(100%).The significant improvements in the photocatalytic performance and stability can be attributed to the intimate interfacial contacts and rich active sites of 0D/1D geometry,fast charge carrier migration,and outstanding photoredox properties induced by the S-scheme charge-transfer *** work offers a promising strategy for constructing 0D/1D S-scheme heterojunction photocatalysts for improved photocatalytic performance.

摘要：Si C nanowires are excellent high-temperature electromagnetic wave (EMW) absorbing materials. However, their polymer matrix composites are difficult to work at temperatures above 300℃, while their ceramic matrix composites must be prepared above 1000℃ in an inert atmosphere. Thus, for addressing the abovementioned problems, SiC/low-melting-point glass composites were well designed and prepared at 580℃ in an air atmosphere. Based on the X-ray diffraction results, SiC nanowires were not oxidized during air atmosphere sintering because of the low sintering temperature. Additionally, SiC nanowires were uniformly distributed in the glass matrix material. The composites exhibited good mechanical and EMW absorption properties. As the filling ratio of SiC nanowires increased from 5wt%to 20wt%, the Vickers hardness and flexural strength of the composite reached HV 564 and 213 MPa, which were improved by 27.7%and 72.8%, respectively, compared with the low-melting-point glass. Meanwhile, the dielectric loss and EMW absorption ability of SiC nanowires at 8.2–12.4 GHz were also gradually improved. The dielectric loss ability of low-melting-point glass was close to 0. However, when the filling ratio of SiC nanowires was 20wt%, the composite showed a minimum reflection loss (RL) of-20.2 dB and an effective absorption (RL≤-10 dB) bandwidth of2.3 GHz at an absorber layer thickness of 2.3 mm. The synergistic effect of polarization loss and conductivity loss in SiC nanowires was responsible for this improvement.

摘要：Aqueous hybrid supercapacitors(AHSCs)offer potential safety and eco-friendliness compared with conventional electrochemical energy storage devices that use toxic and flammable organic *** can serve as the bridge between aqueous batteries and aqueous supercapacitors by combining the advantages of high energy of the battery electrode and high power as well as long lifespan of the capacitive *** the past few decades,extensive research efforts have been devoted to developing advanced materials and fascinating device architectures for ***,further development related to the compatibilities between the battery-type electrode and capacitive electrode remains stagnant mainly due to discrepancy encountered in terms of reaction kinetics and *** review focuses on the recent progress made in the field of AHSCs via elucidating the main concepts on the design of battery and capacitive electrodes and emerging *** particular,ingenious AHSCs that possess either better flexibility toward materials selection or better device functionality such as those with“dual-ion”energy storage mechanism and non-polarity feature are also *** advances and unresolved issues in multivalent ion hybrid devices(in particular,zinc-ion AHSCs)are further ***,future research directions and challenges for AHSCs are presented,which are anticipated to deliver higher energy and demonstrate greater multifunctionalities for more breakthrough technology applications.

摘要：Efficient catalysts enable MgH2 with superior hydrogen storage ***,we successfully synthesized a catalyst composed of Ce and Ni (***_(5) alloy) with splendid catalytic action for boosting the hydrogen storage property of magnesium hydride (MgH_(2))The MgH2–5wt%CeNi_(5) composite’s initial hydrogen release temperature was reduced to 174℃ and approximately 6.4wt%H_(2) was released at 275℃ within 10 ***,the dehydrogenation enthalpy of MgH_(2) was slightly decreased by adding CeNi_(5).For hydrogenation,the fully dehydrogenated sample absorbed 4.8wt%H_(2) at a low temperature of 175℃.The hydrogenation apparent activation energy was decreased from(73.60±1.79) to (46.12±7.33) kJ/*** analysis revealed that Mg_(2)Ni/Mg_(2)NiH_(4) and CeH_(2.73) were formed during the process of hydrogen absorption and desorption,exerted combined“Gateway”and“Spillover”effects to reduce the operating temperature and improve the hydrogen storage kinetics of MgH_(2).Our work provides an example of merging“Gateway”and“Spillover”effects in one catalyst and may shed light on designing novel highly-effective catalysts for MgH_(2) in near future.

摘要：Conjugated covalent organic frameworks(COFs)hold great promise in photocatalytic hydrogen evolution owing to their high crystallinity,large surface area,and distinct ***,COFs exhibit poor charge ***,investigating highly effective COF-based photocatalysts is *** the first time,conjugated COF/perylene diimide urea polymer(PUP)all-organic heterostructure with S-scheme interfacial charge-transfer channels was successfully developed and manufactured via in situ coupling of the two-dimensional triazine-based imine-linked COF(denoted as TATF-COF)with *** optimal photocatalytic hydrogen-evolution rate of 94.5 mmol h^(-1) g^(-1) for TATF-COF/PUP is 3.5 times that of pure TATF-COF and is comparable to or even higher than that of the previously reported COF-based photocatalysts,resulting in an apparent quantum efficiency of up to 19.7%at 420 *** improved directional S-scheme charge transfer driven by the tuned built-in electric field and enhanced oxidation and reduction reaction rates of the photogenerated carriers contribute synergistically to the boosted photocatalytic H_(2) *** and theoretical studies reveal plausible H_(2) evolution and spatial S-scheme charge-separation mechanisms under visible-light *** study provides advanced methods for constructing all-organic S-scheme high-efficiency photocatalysts by the modulation of band structures.

摘要：Construction of multi-channels of photo-carrier migration in photocatalysts is favor to boost conversion efficiency of solar energy by promoting the charge separation and ***,a ternary ZnIn_(2)S_(4)/g-C_(3)N_(4)/Ti_(3)C_(2) MXene hybrid composed of S-scheme junction integrated Schottky-junction was fabricated using a simple hydrothermal *** the components(g-C_(3)N_(4),ZnIn_(2)S_(4) and Ti_(3)C_(2) MXene)demonstrated two-dimensional(2D)nanosheets structure,leading to the formation of a 2D/2D/2D sandwich-like structure with intimate large interface for carrier ***,the photogenerated carriers on the g-C_(3)N_(4) possessed dual transfer channels,including one route in S-scheme transfer mode between the g-C_(3)N_(4) and ZnIn_(2)S_(4) and the other route in Schottky-junction between g-C_(3)N_(4) and Ti_(3)C_(2) ***,a highly efficient carrier separation and transport was realized in the ZnIn_(2)S_(4)/g-C_(3)N_(4)/Ti_(3)C_(2) MXene *** ternary sample exhibited wide light response from 200 to 1400 nm and excellent photocatalytic H_(2) evolution of 2452.1μmol∙g^(–1)∙h^(–1),which was 200,3,1.5 and 1.6 times of g-C_(3)N_(4),ZnIn_(2)S_(4),ZnIn_(2)S_(4)/Ti_(3)C_(2) MXene and g-C_(3)N_(4)/ZnIn_(2)S_(4) binary *** work offers a paradigm for the rational construction of multi-electron pathways to regulate the charge separation and migration via the introduction of dual-junctions in catalytic system.

摘要：The rapid recombination of photo-generated electron-hole pairs,insufficient active sites,and strong photocorrosion have considerably restricted the practical application of Cd S in photocatalytic ***,we designed and constructed a 2D/2D/2D layered heterojunction photocatalyst with cascaded 2D coupling *** using electron spin resonance spectroscopy,ultraviolet photoelectron spectroscopy,and in-situ irradiation X-ray photoelectron spectroscopy were conducted to confirm the 2D layered CdS/WO_(3) step-scheme(S-scheme)heterojunctions and CdS/MX ohmic ***,it was found that the strong interfacial electric fields in the S-scheme heterojunction photocatalysts could effectively promote spatially directional charge separation and transport between CdS and WO_(3) *** addition,2D Ti_(3)C_(2) MXene nanosheets with a smaller work function and excellent metal conductivity when used as a co-catalyst could build ohmic junctions with Cd S nanosheets,thus providing a greater number of electron transfer pathways and hydrogen evolution *** showed that the highest visible-light hydrogen evolution rate of the optimized MX-Cd S/WO_(3) layered multi-heterostructures could reach as high as 27.5 mmol/g/h,which was 11.0 times higher than that of pure CdS ***,the apparent quantum efficiency reached 12.0% at 450 *** is hoped that this study offers a reliable approach for developing multifunctional photocatalysts by integrating S-scheme and ohmic-junction built-in electric fields and rationally designing a 2D/2D interface for efficient light-to-hydrogen fuel production.