High-performance lithium-ion batteries based on polymer/graphene hybrid cathode material

Organic and carbon-based lithium-ion batteries possess abundant resources,nontoxicity,environmental friendliness,and high performance,and they have been widely studied in the past decades.However,it remains a challenge to construct such batteries with high capacity,high cycling stability,and high conductivity simultaneously.Here,we elaborately design and integrate organic polymer(p-FcPZ) with graphene network to create a hybrid material(p-FcPZ@G) for high-performance lithium-ion batteries(LIBs)....     

Manipulating interfacial stability of LiNi0.5Co0.3Mn0.2O2 cathode with sulfide electrolyte by nanosized LLTO coating to achieve high-performance all-solid-state lithium batteries

All-solid-state lithium batteries(ASSLBs) based on sulfide solid-state electrolytes and high voltage layered oxide cathode are regarded as one of the most promising candidates for energy storage systems with high energy density and high safety.However,they usually suffer poor cathode/electrolyte interfacial stability,severely limiting their practical applications.In this work,a core-shell cathode with uniformly nanosized Li0.5La0.5TiO3(LLTO) electrolyte coating on LiNi0.5Co0.3Mn0.2O2(NCM532) is designed to improve the cathode/electrolyte interface stability.Nanosized LLTO coating layer not only significantly boosts interfacial migration of lithium ions,but also efficiently alleviates space-charge layer and inhibits the electrochemical decomposition of electrolyte.As a result,the assembled ASSLBs with high mass loading(9 mg cm-2)LLTO coated NCM532(LLTO@NCM532) cathode exhibit high initial capacity(135 mAh g^-1) and excellent cycling performance with high capacity retention(80% after 200 cycles) at 0.1 C and 25℃.This nanosized LLTO coating layer design provides a facile and effective strategy for constructing high performance ASSLBs with superior interfacial stability.     

High and ultra-stable energy storage from all-carbon sodium-ion capacitor with 3D framework carbon as cathode and carbon nanosheet as anode

Sodium-ion capacitors(SICs)are extremely promising due to the combined merits of high energy-power characteristics and considerable price advantage.However,it is still difficult to achieve high energypower outputs and cycle stability in a typical configuration of the metal-based battery-type anode and activated carbon capacitor-type cathode due to the kinetic mismatching.In this work,a carbon nanosheet(PSCS-600)with large interlayer spacing of 0.41 nm derived from the bio-waste pine cone shell was prepared.Besides,the covalent triazine framework derived carbon(OPDN-CTF-A)was obtained through ionothermal synthesis strategy,exhibiting beneficial hierarchical pores(0.5-6 nm)and high heteroatoms(5.6 at%N,6.6 at%O).On this basis,the all-carbon SICs were fabricated by the integration of PSCS-600 anode and OPDN-CTF-A cathode.The device delivered high energy density 111 Wh kg^-1,high power output of 14,200 W kg^-1 and ultra-stable cycling life(~90.7%capacitance retention after 10,000 cycles).This work provides new ideas in fabricating carbon-carbon architectural SICs with high energy storage for practical application.     

Pyridinic nitrogen enriched porous carbon derived from bimetal organic frameworks for high capacity zinc ion hybrid capacitors with remarkable rate capability

Aqueous zinc ion hybrid capacitors(ZIHCs)hold great potential for large-scale energy storage applications owing to their high safety and low cost,but suffer from low capacity and energy density.Herein,pyridinic nitrogen enriched porous carbon(nPC)was successfully synthesized via the growth,subsequent annealing and acid etching of bimetal organic frameworks for high capacity and safe ZIHCs with exceptional rate capability.Benefiting from the mesopores for easy ion diffusion,high electrical conductivity enabled by in-situ grown carbon nanotubes matrix and residual metal Co nanoparticles for fast electron transfer,sufficient micropores and high N content(8.9 at%)with dominated pyridinic N(54%)for enhanced zinc ion storage,the resulting nPC cathodes for ZIHCs achieved high capacities of 302 and137 m Ah g^-1 at 1 and 18 A g^-1,outperforming most reported carbon based cathodes.Theoretical results further disclosed that pyridinic N possessed larger binding energy of-4.99 eV to chemically coordinate with Zn2+than other N species.Moreover,quasi-solid-state ZIHCs with gelatin based gel electrolytes exhibited high energy density of 157.6 Wh kg^-1 at 0.69 kW kg^-1,high safety and mechanical flexibility to withstand mechanical deformation and drilling.This strategy of developing pyridinic nitrogen enriched porous carbon will pave a new avenue to construct safe ZIHCs with high energy densities.     

Facile Synthesis of Functional Poly(methyltriazolylcarboxylate)s by Solvent-and Catalyst-free Butynoate-Azide Polycycloaddition

The copper-catalyzed and metal-free azide-alkyne click polymerizations have become efficient tools for polymer synthesis. However,the 1,3-dipolar polycycloadditions between internal alkynes and azides are rarely employed to construct functional polymers. Herein, the polycycloadditions of dibutynoate(1) and tetraphenylethene-containing diazides(2) were carried out at 100 °C for 12 h under solvent-and catalyst-free conditions, producing soluble poly(methyltriazolylcarboxylate)s(PMTCs) with high molecular weights in high yields. The resultant polymers were thermally stable with 5% weight loss temperatures up to 377 °C. The PMTCs showed aggregation-induced emission(AIE)properties. They could work as fluorescent sensors for detecting explosive with high sensitivity, and generate two-dimensional fluorescent photopatterns with high resolution. Furthermore, their triazolium salts could be utilized for cell-imaging applications.     

Proton Conductivity Improvement Effect of Cellulose on SPEEKK Based PEM

The proton exchange membranes(PEMs) were prepared through the solution mixing method of sulfonated poly(etlier ether ketone ketoneXsPEEKK) and cellulose. Cellulose was dissolved by 1-ally 1-3-methylimidazolium chioride(AMIMC1) and then mixed with sPEEKK solution. sPEEKK/cellulose(SC) composite membranes were prepared by solution casting. The membranes have high flexibility and transparency, which meant the compounding in molecular level. Meanwhile, the composite membranes showed excellent mechanical properties and high proton conductivity. The mechanical property reached 29 MPa, and the proton conductivity was as high as 0.32 S/cm. Thus, as a kind of biomaterials, cellulose could be ail excellent reinforcing material for poly(aryl ether ketone)(PAEK) based PEMs.     

Enhancing the Surface Stability of Ni-Rich Layered Transition Metal Oxide Cathode Materials

<正>Rechargeable Li-ion batteries have gained prominence because they offer unparalleled high energy density and high voltage capability. They are already widely used in portable electronic devices and electric vehicles. One of the most promising cathode materials, the Ni-rich LiNi_xMn_yCo_(1-x-y)O_2(x ≥ 0.6) cathode(Ni-rich NMC) has been extensively studied because its high Ni content enables high specific capacity     

MORPHOLOGY AND MECHANICAL PROPERTIES OF POLY(ETHYLENEOCTENE) COPOLYMERS OBTAINED BY DYNAMIC PACKING INJECTION MOLDING*

The morphology and mechanical properties of poly(ethylene-octene)copolymers(POE)obtained by dynamic packing injection molding were investigated by mechanical tests,differential scanning calorimetry(DSC),fourier transform infrared spectroscopy(FT-IR)and scanning electron microscopy(SEM).The mechanical tests found that only POE with low octene content and high molecular weight show apparent response for external shear field.Further investigation has been done by DSC,FT-IR,and SEM in order to make clear the reason of that phenomenon.Finally,the hypothetical mechanism of POE microstructure formation under shear field has been proposed.For POE with low octene content and high molecular weight,orientation degree and mechanical properties both increase substantially under shear field.For POE with low octene content and low molecular weight,orientation degree and crystallinity increase under shear field,but it is not dramatically benefit for the mechanical properties.For POE with high octene content and high molecular weight,the shear field has little effect on the morphology and mechanical properties.     

The preparation of supported ionic liquids (SILs) and their application in rare metals separation

This review summarizes the preparation methods of support ionic liquids (SILs) and their applications in rare metals separation. The rare metals separation includes the recovery of high value metal ions and the removal of heavy metal ions from wastewater. SILs can be used as a kind of highly efficient multifunctional separation materials. The preparation methods of SILs include chemical immobilization technique in which ILs moieties are supported on solid supports via covalent bonds and physical immobilization techniques in which ILs are immobilized on solid supports via physical method such as simple im- pregnation, sol-gel method. According to the difference of solid supports, this review summarizes the application of polymer supported ionic liquids (P-SILs), silica based material supported ionic liquids (SM-SILs) and membrane supported ionic liq- uids (M-SILs) in rare metals separation. P-SILs and SM-SILs prepared by chemical method with N-methylimidazolium group can be used as highly efficient anion exchangers with high thermal stability and good chemical stability for adsorption of Cr(VI), Re(VII), Ce(IV). P-SILs prepared via simple impregnation afforded IL functionalized solvent impregnated resins (SIRs) which showed high separation efficiency and selectivity in the separation of rare earths(III) (REs(III)). SM-SILs prepared via sol-gel method with IL doped in the support as porogens or extractant show high removal efficiencies and excellent stability for the separation of RE(III), Cr(III) and Cr(VI). M-SILs with IL as plasticizer or carrier show improved stability, high perme- ability coefficient and good selectivity for Cr(VI) transport. Different supports and different supporting methods were suffi- ciently compared. Based on the different practical application, different forms of SILs can be prepared for separation of rare metals with high separation efficiency and selectivity.     

剖析液相色谱柱技术的复杂状况(英文)

 Column packings continue to evolve as the needs of users for high efficiency, high resolution and highly sensitive high performance liquid chromatographic (HPLC) analysis drive further developments. In comparing and contrasting modern HPLC columns technologies, diameters of column packings and particle materials are covered. Some products and applications of modern HPLC columns are provided. Future directions in packing developments are predicted in this introductory article.     

高效膜色谱的发展和应用

对新兴的高效膜色谱的基质材料、膜形态、分离机理以及应用进行了综述,并对其用于对映体分离作了展望。共７６篇。     

MCM-48介孔分子筛的高压合成

采用正硅酸乙酯（TEOS）作硅源,十六烷基三甲基溴化铵（CTAB）为模板剂,在高压 （约7 MPa）和373 K下合成了MCM-48介孔分子筛.用XRD、氮气吸附及29Si MAS NMR对样品 进行了表征.与常压合成的相比,高压下合成的MCM-48具有更高的热稳定性和水热稳定性.2 9Si MAS NMR结果表明,高压有利于分子筛孔壁的聚合,导致分子筛结构更加完善,从而使 其具有更高的稳定性.     

SPEEK/PES-C、SPEEK/SPES-C共混质子交换膜研究

通过在磺化聚醚醚酮(SPEEK,DS=61.68%)中分别混入酚酞型聚醚砜(PES-C)、磺化酚酞型聚醚砜(SPES-C,DS=53.7%)制备出SPEEK/PES-C、SPEEK/SPES-C共混质子交换膜.结果表明,共混的两种聚合物之间均具有较好的相容性.PES-C、SPES-C的混入能有效降低膜的溶胀及甲醇透过,且随着共混量的增加,这种作用越趋明显.纯SPEEK膜在75℃左右溶解,而SPEEK/PES-C(30 wt%)、SPEEK/SPES-C(30 wt%)共混膜在80℃时溶胀度仅为22.5%、26.32%.在室温至80℃范围内,纯SPEEK及共混膜的甲醇透过系数都在10-7 cm2·s-1数量级上,远小于Nation[R]115膜.在饱和湿度下,温度大于90℃时,SPEEK/PES-C(20 wt%)共混膜电导率超过Nation[R]115膜;温度大于110℃时,SPEEK/SPES-C(30 wt%)共混膜电导率与Nafion[R]115膜相当,达到0.11 S·cm-1.高电导率,低透醇系数以及明显提高了的可使用温度表明该类共混膜有望在DMFC中使用.     

新型双极有机小分子化合物及其Al3+配合物的合成与发光

合成了一种新的具有“双极”(bipolar)性质的有机小分子蓝色发光材料2-(5-(4-(二苯胺基)苯基)-1,3,4-噁二唑-2-)苯酚［2(5-(4-(diphenylamino)phenyl)-1,3,4-oxadiazol-2-yl)phenol, HPOT］, 并以HPOT为配体, 与铝离子配位, 合成了三(2-(5-(4-(二苯胺基)苯基) 1,3,4-噁二唑-2-)苯酚)合铝［tri(2-(5-(4-(diphenylamino)phenyl)-1,3,4-oxadiazol-2-yl)phenonate)aluminum, AlPOT］配合物. 用 1 H NMR、 HRMS和元素分析进行了表征, 并测定了两种化合物的光致发光性质和热稳定性. 结果表明: 两种新化合物的热稳定性好, 光致发光性能优良, 是制作有机电致发光器件的候选材料.     

Poly(3,4-ethylenedioxythiophen)/Poly(4-styrenesul-fonate): Thin Films and Microfibers

This Feature Article describes our recent researches on processing poly(3,4-ethylenedioxythiophene /poly(4-styrenesulfonate) (PEDOT/PSS) colloidal dispersion into thin films which exhibit high conductivity and high transparency, and into microfibers which exhibit high conductivity and high mechanical strength. The state-of-the-art thin films and microfibers are expected to utilize to sophisticated touch screens and wearable electronic devices as organic transparent electrodes and woven electric circuits, respectively.     

High‐efficiency organic electroluminescent devices using iridium complex emitter and arylamine‐containing polymer buffer layer

We have developed efficient organic electroluminescent (EL) devices using a phosphorescent material, tris(2‐phenylpyridine) iridium, Ir(ppy)₃, as an emitter material and a polymer buffer layer, tetraphenyldiamine‐containing poly(arylene ether sulfone) (PTPDES) doped with tris(4‐bromophenyl) aminium hexachloroantimonate (TBPAH) as an electron acceptor. In this device, a high external quantum efficiency of 21.6% and a luminous efficiency of 82 lm/W (77 cd/A) at 3.0 V were obtained. These high efficiencies can be explained by high quantum efficiency due to phosphorescent Ir(ppy)₃ and high luminous efficiency realized by the use of the polymer buffer layer. Copyright © 2002 John Wiley & Sons, Ltd.     

Synthesis and characterization of alkaline‐soluble triazine‐based poly(phenylene sulfide)s with high refractive index and low birefringence

High‐refractive‐index (high‐n) polymers (HRIPs) with a high optical transparency are highly needed in advanced optoelectronic devices. In this work, we report the synthesis and characterization of a series of high‐n, transparent, totally colorless, and high‐sulfur‐containing poly(phenylene sulfide)s (PPSs) bearing a triazine unit. Two new triazine monomers T1 and T2 with hydroxyl and tert‐butyl acetate side chains, respectively, were designed and synthesized to develop PPSs with high‐n and high alkaline solubility. These PPSs were prepared by the single‐phase polycondensation from T1 / T2 and commercial aromatic dithiols such as 4,4′‐thiobisbenzenethiol ( TBT ) and benzene‐1,3‐dithiol ( BDT ), achieving very high‐n up to 1.7530 at 633 nm, a high optical transparency (T% > 90% @400 nm) and low birefringence (Δn = 0.0014–0.0080), and exhibiting high potential on the application of high‐n photoresists. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 724–731     

磺化聚醚醚酮/三羧基丁烷膦酸锆复合质子交换膜的研究

通过在磺化聚醚醚酮(SPEEK)中掺杂1,2,4-三羧基丁烷-2-膦酸锆(Zr(PBTC))制备出SPEEK/Zr(PBTC)复合质子交换膜.结果表明,与纯SPEEK膜相比,Zr(PBTC)的掺杂能降低复合膜的吸液量及甲醇透过系数,且随着Zr(PBTC)含量的增加,这种作用越趋明显.在室温至80℃范围内,复合膜的甲醇透过系数在10-7cm2.s-1数量级上,远小于Nafion115膜.在饱和湿度下,当温度大于90℃时,含40wt%Zr(PBTC)的复合膜电导率超过Nafion115膜,并在160℃时达到0.36S.cm-1.使用温度的提高及在高温下的高电导率表明该复合膜适合在高温DMFC中使用.     

耐高温碳化硅纤维的制备与性能

采用聚硅碳硅烷（PSCS）与乙酰丙酮铝反应，合成出聚铝碳硅烷（PACS）陶瓷先驱体聚合物.经熔融纺丝、空气不熔化、烧成与高温烧结等工艺， 制备性能优异的耐高温碳化硅纤维SiC(Al).经29Si MAS NMR、 XRD、 Raman谱、AES与SEM等一系列分析表明，该纤维的化学组成和结构与普通碳化硅纤维显著不同，具有近化学计量比组成，氧、游离碳以及SixCyOz相的含量大大低于普通碳化硅纤维，这是其高温稳定的主要原因.在制备过程中铝作为烧结助剂起到了使纤维致密化与抑制晶粒快速增长的作用.     

A highly active neodymium chloride isopropanol complex/modified methylaluminoxane catalyst for preparing polyisoprene with high cis-1,4 stereospecificity and narrow molecular weight distribution

<正>Neodymium chloride isopropanol complex(NdCl_3·3~iPrOH) activated by modified methylaluminoxane(MMAO) was examined in isoprene polymerization in hexane,with regards to Nd compounds,aluminum(Al) compounds,[Al]/[Nd] ratio,polymerization temperature and time.NdCl_3-3~iPrOH exhibited high activity producing polymers featuring high cis-1,4 stereospecificity(96%),very high molecular weight(M_n1.0×10~6) and fairly narrow molecular weight distribution (MWD,M_w/M_n2.0) simultaneously.In comparison,neodymium isopropoxide also showed high activity providing polymers with narrow MWD(M_w/M_n = 2.07),but somewhat low cis-1,4 content(ca.92%),while neodymium chloride had no activity under present polymerization conditions.The Al compounds affected the polymer yield in the order of Al(i-Bu)_3MMAOAl(i-Bu)_2H.MMAO as cocatalyst afforded polyisoprene with high M_n over 1.0×10~6,whereas as stronger chain transfer agent than MMAO,Al(i-Bu)_3 and Al(i-Bu)_2H yielded polymers with low M_n(1.0×10~5-8.0×10~5). NdCl_3·3~iPrOH/MMAO catalyst showed a fairly good catalytic activity even at relatively low[Al]/[Nd]ratio of 30,and the produced polymer remained high cis-1,4 content of 95.8%along with high M_n over 1.0×10~6 even at elevated temperatures up to 70℃.The polymerization rate is of the first order with respect to the concentration of isoprene.The mechanism of active species formation was discussed preliminarily.