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Nano Research 2019年第11期12卷 2872-2880页

作者： xiaojun zhao Dan Luo Yan Wang Zhi-Hong Liu Key Laboratory for Macromolecular Science of Shaanxi Province School of Chemistry and Chemical EngineeringShaanxi Normal UniversityXi’an710062China

Rational synthesis of a hierarchical porous architecture with highly active and consecutive conductive network is very critical to achieve the high-performance of nanomaterials in electrochemical energy conversion and *** propose here a hierarchical micro-/nanostructured hybrids constructed by the dual carbon shell nanowire host containing CoP nanocrystals of several nanometers,which generates Co-based metal-organic framework on graphene oxide nanosheets in situ and followed a direct phosphorization(CoP@NC/rGO).The dual carbon shell,consisting of Co-based metal-organic framework derived porous doped carbon(NC)and reduced graphene oxide(rGO),can not only impedes CoP nanocrystals from coalescing,and renders highly exposed the electrochemically accessible active sites,but also provides the multidimensional pathways for rapid electron and ion *** importantly,the covered dual carbon shell on CoP nanocrystals plays a role as a protective layer to impede the nanocrystals’*** virtue of compositional and structural advantages,the micro-/nanostructured CoP@NC/rGO hybrids manifest outstanding energy storage properties when evaluated as anodes for lithium/sodium ion ***,it also reveals highly efficient electrocatalytic performance for hydrogen evolution reaction in acid media with low Tafel slope,overpotential and robust durability.

关键词： micro-/nanostructured metal-organic framework CoP@NC/rGO lithium/sodium ion batteries hydrogen evolution reaction

Highly active CoP-CO_(2)N confined in nanocarbon enabling efficient electrocatalytic immobilizing-conversion of polysulfide targeting high-rate lithium-sulfur batteries

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Journal of Energy Chemistry 2022年第12期75卷 250-259,I0006页

作者： xiaojun zhao Tianqi Gao Wenhao Ren Chuan zhao Zhi-Hong Liu Linbo Li School of Metallurgical Engineering Xi'an University of Architecture and TechnologyXi'an 710055ShaanxiChina School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi’an 710062ShaanxiChina School of Chemistry University of New South WalesSydneyNSW 2052Australia

Lithium-sulfur batteries suffer from poor cycling stability because of the intrinsic shuttling effect of intermediate polysulfides and sluggish reaction kinetics,especially at high rates and high sulfur ***,we report the construction of a CoP-CO_(2)N@N-doped carbon polyhedron uniformly anchored on three-dimensional carbon nanotubes/graphene(CoP-CO_(2)N@NC/CG)scaffold as a sulfur reservoir to achieve the trapping-diffusion-conversion of *** active CoP-CO_(2)N shows marvelous catalytic effects by effectively accelerating the reduction of sulfur and the oxidation of Li_(2)S during the discharging and charging process,respectively,while the conductive NC/CG network with massive mesoporous channels ensures fast and continuous long-distance electron/ion *** calculations demonstrate that the CoP-CO_(2)N with excellent intrinsic conductivity serves as job-synergistic immobilizing-conversion sites for polysulfides through the formation of P…Li/N…Li and Co…S *** a result,the S@CoP-CO_(2)N@NC/CG cathode(sulfur content 1.7 mg cm^(-2))exhibits a high capacity of988 mAh g^(-1)at 2 C after 500 cycles,which is superior to most of the electrochemical performance *** under high sulfur content(4.3 mg cm^(-2)),it also shows excellent cyclability with high capacity at 1 C.

关键词： CoP-CO_(2)N@NC/CG Trapping-diffusion-conversion High-rate DFT calculation Li-S battery

Revealing the Unusual Efficiency Enhancement of Organic Solar Cells with Polymer-Donor-Treated Cathode Contacts

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Chinese Journal of Polymer Science 2022年第8期40卷 937-943,I0009页

作者： Zesheng Liu Yawen Li xiaojun zhao Yufan Zhu Yuze Lin Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing100190China University of Chinese Academy of Sciences Beijing100049China

The metal oxides with low trap density of states as the electron transport layer are crucial for the high performance of the organic solar cells(OSCs).It is universally acknowledged that modifying n-type metal oxide contacts with polymer donors will harm the carrier extraction on account of the mismatched energy ***,we find that modifying interlayer consisting of the alcohol amines with some polymer donor additive can unusually enhance the performance of the *** with triethanolamine(TEA)passivated ZnO,TEA:polymer donor treated ZnO shows lower trap density and enhances electron mobility resulting in higher current density in OSC ***,we reveal that the enhanced oxygen-defect passivation ability of TEA with polymer additive is attributed to the enhanced negative electrostatic potential of TEA owing to the hydrogen bond formation between the polymer and the hydroxyl group in *** strategy that enhancing the negative electrostatic potential of the passivators for improving oxygen defect passivation can be extended to other types of organic electronic devices.

关键词： Organic solar cell Electron transport layer Trap density Passivation Hydrogen bond

Preparation of a tantalum-based MoSi_(2)–Mo coating resistant to ultra-high-temperature thermal shock by a new two-step process

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Journal of Materials Science & Technology 2021年第22期81卷 117-122页

作者： Sainan Liu Hongtai Shen Jiawei Xu xiaojun Zhou Jianfei Liu Zhenyang Cai xiaojun zhao Lairong Xiao School of Materials Science and Engineering Central South UniversityChangshaHunan410083China Center for Mineral Materials School of Minerals Processing and BioengineeringCentral South UniversityChangsha410083HunanChina Key Laboratory of Non-ferrous Metal Materials Science and Engineering Ministry of EducationCentral South UniversityChangsha410083China

To develop an ultra-high-temperature resistant coating for a reusable thermal protection system,the preparation of a tantalum-based MoSi_(2)-Mo coating by a new two-step process of multi-arc ion plating and halide activated pack cementation is *** coating has a dense structure and is well compatible with the tantalum substrate,which can be thermally shocked from room temperature to 1750℃ for 360 cycles without *** mechanism of the coating’s excellent resistance to high-temperature thermal shocks is that a strong-binding gradient interface and a dense SiO_(2) oxide scale with good oxygen resistance are formed by the high-temperature self-diffusion of Si.

关键词： Thermal shock MoSi_(2) Tantalum Multi-arc ion plating Pack cementation

Application research of a novel designed peptide as a potential carrier

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Science China Chemistry 2009年第5期52卷 632-638页

作者： RUAN LiPing ZHANG HangYu LUO HanLin zhao xiaojun Institute for Nanobiomedical Technology and Membrane Biology West China HospitalSichuan UniversityChengdu 610041China

While a great deal of research has focused on the application of full-sequence ionic complementary peptide, detection of the capability of half-sequence ionic complementary peptide such as drug carriers, is rarely reported. This paper presents that the half-sequence ionic complementary peptide P9 (AC-Pro- Ser-Phe-Asn-Phe-Lys-Phe-Glu-Pro-NH2) can successfully stabilize a model hydrophobic drug pyrene in the aqueous solution. Soybean lecithin vesicles were used to mimic plasma membranes. Fluorescence data show that the pyrene is presented in the crystalline form when stabilized by P9 solution, and molecularly migrated from its peptide encapsulations into the membrane bilayers when the suspension is mixed with lipidosome vesicles. Slower release was observed when thicker coating was applied onto pyrene, which could be to control the wall thickness coating the cargo, and consequently the release rate. The result indicated that P9, with half-sequence ionic complement, may serve as a hydrophobic compounds carrier.

关键词： peptide half-sequence ionic complement delivery pyrene fluorescence spectroscopy

Ultrathin MoS2 with expanded interlayers supported on hierarchical polypyrrole-derived amorphous N-doped carbon tubular structures for high-performance Li/Na-ion

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Nano Research 2018年第7期11卷 3603-3618页

作者： xiaojun zhao Gang Wang Xiaojie Liu Xinliang Zheng Hui Wang Key Laboratory of Synthetic and Nature Functional Molecule Chemistry (Ministry of Education) Department College of Chemistry and Materials Science Northwest University Xi'an 710127 China Department of Chemistry and Chemical Engineering Ankang University Ankang 725000 China National Key Laboratory of Photoelectric Technology and Functional Materials (Culture Base) National Photoelectric Technology and Functional Materials and Application International Cooperation Base Institute of Photonics and Photon-Technology Northwest University Xi'an 710127 China School of Physics Northwest University Xi'an 710069 China

Layered molybdenum disulfide （MoS2） has received much attention as one of the most promising energy-storage and conversion materials for Li/Na ion batteries. Here, a simple and effective approach is proposed for the rational design and preparation of hierarchical three-d imensional （3D） amorphous N-doped carbon nanotube@MoS2 nanosheets （3D-ANCNT@MoS2） via a simple hydrothermal method, followed by an annealing process. With such a unique nanoarchitecture, ultrathin MoS2 nanosheets grown on the external surfaces of polypyrrole-derived ANCNTs are assembled to form a hierarchical 3D nanoarchitecture, where the adopted ANCNTs serve not only as the template and continuous conductive matrix, but can also prevent MoS2 from aggregating and restacking, and help to buffer the volumetric expansion of MoS2 during cycling. More importantly, when evaluated as an anode material for lithium-ion batteries, the 3D-ANCNT@MoS2 composite exhibits excellent cycling stability, superior rate performance, and reversible specific capacity as high as 893.4 mAh·g^-1 at 0.2 A·g^-1 after 200 cycles in a half battery, and 669.4 mAh·g^-1 at 0.2 A·g^-1 after 100 cycles in the 3D-ANCNT@Mo2//LiCoO2 full battery. With respect to sodium-ion batteries, the outstanding reversible capacity, excellent rate behavior, and good cycling performance of 3D-ANCNT@MoS2 composites are also achieved.

关键词： MoS2 nanosheets expanded interlayers N-doped carbon nanotubes Li/Na ion batteries

Microstructures and Key Properties of Mechanically Deposited Zn-Al Coatings

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Chinese Journal of Mechanical Engineering 2009年第4期22卷 608-613页

作者： WANG Shengmin HE Mingyi zhao xiaojun PENG Zenghua LIU Li Faculty of Mechanical and Electrical Engineering Kunming University of Science and Technology Kunming 650093 China Faculty of Chemistry and Biotechnology Yunnan Nationalities University Kunming 650031 China

Zn-Al coatings can provide protection to exposed steel parts in most environments. For this reason, the investigation of Zn-Al coatings become very popular in recent years. In order to study the microstructures and properties of mechanically deposited Zn-Al coating, zinc powders and aluminum powders were used to deposit Zn-AI coating by mechanical plating. The microstruetures, phase constitutes and compositions of the coating were observed and analyzed with optical microscopy （OM）, scanning electron microscopy（SEM）, X-ray diffraction（XRD） and X-ray energy-dispersive spectroscopy（EDS）. The results of observation show that the coating consists of almost spherically shaped zinc particles point contacting with each other; the coatings are composed of zinc particles, aluminum particles, interstice, and tin; extra fine zinc powders and some smaller interspersed inclusions are positioned in the interstices. Porosity and thickness of the coating were tested by ferroxyl test and magnetic method. The corrosion resistance of coatings was studied by neutral salt spraying test（NSS）, immersion test and electrochemical polarization. It is found that the thickness of the coating dose lacks uniformity, with an uneven thickness distribution and an average variation of approximately 2-5gm; the coating can afford cathodic protection to the steel substrate; the corrosion resistance of Zn-Al coatings is better than that of the mechanically plated zinc coatings with same thickness. These conclusions can be applied to improve anti-corrosion performance by mechanically deposit Zn-Al coatings.

关键词： mechanical plating Zn-Al coatings microstructure porosity corrosion resistance

Preparation of Novel Dechlorination Adsorbent and Study on Its Adsorption Mechanism

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China Petroleum Processing & Petrochemical Technology 2017年第4期19卷 20-26页

作者： Chen Jiqun zhao xiaojun Zou Ying Petroleum Processing Institute East China University of Science and Technology Shanghai 200237

The preparation of novel dechlorination adsorbent by using the modified 13 X molecular sieve and its adsorption mechanism were studied. XRD and SEM analyses showed that the Ag-13 X molecular sieve revealed a new crystal plane,while other molecular sieve samples more or less contained some impurities. The BET data showed that only Ag^+ ions could enlarge the pore size and the pore volume at the same time. The NH_3-TPD diagram showed that the acid sites of the adsorbent increased after its modification by metal ions and only the Ag-13 X molecular sieve generated new medium strong acid sites. According to adsorption experiments conducted at different concentration and temperature, the dechlorination adsorption mechanism of Ag-13 X molecular sieve was a combination of physical adsorption and chemical adsorption which showed the different degree of influence at different temperatures.

关键词： organic chlorine adsorption 13X molecular sieve metal modification Ag

Atomic-scale investigation of precipitate phases in QE22 Mg alloy

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Journal of Materials Science & Technology 2024年第10期177卷 114-127页

作者： xiaojun zhao Zhiqiao Li Aiping Zhang Longlong Hao Houwen Chen Jian-Feng Nie Key Laboratory of Advanced Technologies of Materials Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China International Joint Laboratory for Light Alloys(MOE) College of Materials Science and EngineeringChongqing UniversityChongqing 400044China Department of Materials Science and Engineering Monash UniversityVictoria 3800Australia

Precipitation-hardenable commercial Mg alloy QE22(***-0.7Zr,wt.%)has excellent mechan-ical properties,but precipitates in this alloy have not been well *** this work,precipitate phasesγ",γ,andδformed during the isothermal ageing process at 150,200,250,and 300℃have been characterized using atomic-resolution high-angle annular dark-field scanning transmission electron mi-croscopy and atomic-scale energy-dispersive X-ray *** morphology,crystal structure,and orientation relationship of these precipitate phases have been *** boundaries usually exist in a singleγparticle,which can be characterized by a separation vector of[1(1)01]_(α).Theδphase forms in situ from its precursorγphase,consequently leading to the formation of three different variants within a single 8 *** nucleation of theδphase is strongly related to the domain boundaries of the y *** formation of theγphase may be promoted by its precursorγ"*** similarities in atomic structures of theγ",γ,andδphases are described and discussed,indicating that transfor-mations between these precipitate phases can be accomplished through the diffusion of added alloying elements.

关键词： Magnesium alloy Precipitation Phase identification Phase transformation Electron microscopy

A superior strength-ductility synergy of Al_(0.1)CrFeCoNi high-entropy alloy with fully recrystallized ultrafine grains and annealing twins

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Journal of Materials Science & Technology 2022年第36期131卷 185-194页

作者： Jiahao Li Kejie Lu xiaojun zhao Xinkai Ma Fuguo Li Hongbo Pan Jieming Chen Key Laboratory of Advanced Technologies of Materials Ministry of EducationSchool of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China Shenzhen Institute of Southwest Jiaotong University Shenzhen 518000China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Anhui Province Key Laboratory of Metallurgical Engineering&Resources Recycling(Anhui University of Technology) 243002 MaanshanChina Luoyang Ship Material Research Institute Luoyang 471023China

Grain refinement usually makes the materials stronger,while ductility has a dramatic ***,a superior tensile strength–ductility synergy in a fully recrystallized ultrafine-grained(UFG)Al_(0.1)CrFeCoNi with abundant annealing twins was achieved by cold rolling at room temperature and short-time *** microstructure characterization using electron backscattered scattering diffraction demonstrates that abundant geometrically necessary dislocations(GNDs)gather around the grain boundaries and twin boundaries after tensile *** coarse-grained(CG)samples undergo a larger plastic deformation than UFG samples,the GND density decreases with grain size ranging from UFG to *** electron microscopy results reveal that the annealing twin boundary,which effectively hinders the dislocation slip and stores dislocation in grain interior,and the activation of multiple deformation twins are responsible for the superior strength–ductility synergy and work hardening *** addition,the yield strength of fully recrystallized Al_(0.1)CrFeCoNi follows a Hall–Petch relationship(σ_y=24+676d^(–1/2)),where d takes into account both grain boundaries and annealing twin *** strengthening effects of grain boundaries and annealing twin boundaries were also evaluated separately.

关键词： High-entropy alloy Ultrafine grains Annealing twins Strength Ductility