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1.
Zn batteries are usually considered as safe aqueous systems that are promising for flexible batteries. On the other hand, any liquids, including water, being encapsulated in a deformable battery may result in problems. Developing completely liquid-free all-solid-state Zn batteries needs high-quality solid-state electrolytes (SSEs). Herein, we demonstrate in situ polymerized amorphous solid poly(1,3-dioxolane) electrolytes, which show high Zn ion conductivity of 19.6 mS cm−1 at room temperature, low interfacial impedance, highly reversible Zn plating/stripping over 1800 h cycles, uniform and dendrite-free Zn deposition, and non-dry properties. The in-plane interdigital-structure device with the electrolyte completely exposed to the open atmosphere can be operated stably for over 30 days almost without weight loss or electrochemical performance decay. Furthermore, the sandwich-structure device can normally operate over 40 min under exposure to fire. Meanwhile, the interfacial impedance and the capacity using in situ-formed solid polymer electrolytes (SPEs) remain almost unchanged after various bending tests, a key criterion for flexible/wearable devices. Our study demonstrates an approach for SSEs that fulfill the requirement of no liquid and mechanical robustness for practical solid-state Zn batteries.  相似文献   

2.
Lithium–sulfur (Li−S) batteries are promising due to ultrahigh theoretical energy density. However, their cycling lifespan is crucially affected by the electrode kinetics of lithium polysulfides. Herein, the polysulfide solvation structure is correlated with polysulfide electrode kinetics towards long-cycling Li−S batteries. The solvation structure derived from strong solvating power electrolyte induces fast anode kinetics and rapid anode failure, while that derived from weak solvating power electrolyte causes sluggish cathode kinetics and rapid capacity loss. By contrast, the solvation structure derived from medium solvating power electrolyte balances cathode and anode kinetics and improves the cycling performance of Li−S batteries. Li−S coin cells with ultra-thin Li anodes and high-S-loading cathodes deliver 146 cycles and a 338 Wh kg−1 pouch cell undergoes stable 30 cycles. This work clarifies the relationship between polysulfide solvation structure and electrode kinetics and inspires rational electrolyte design for long-cycling Li−S batteries.  相似文献   

3.
Formamidinium lead iodide (FAPbI3) represents an optimal absorber material in perovskite solar cells (PSCs), while the application of FAPbI3 in inverted-structured PSCs has yet to be successful, mainly owing to its inferior film-forming on hydrophobic or defective hole-transporting substrates. Herein, we report a substantial improvement of FAPbI3-based inverted PSCs, which is realized by a multifunctional amphiphilic molecular hole-transporter, (2-(4-(10H-phenothiazin-10-yl)phenyl)-1-cyanovinyl)phosphonic acid (PTZ−CPA). The phenothiazine (PTZ) based PTZ−CPA, carrying a cyanovinyl phosphonic acid (CPA) group, forms a superwetting hole-selective underlayer that enables facile deposition of high-quality FAPbI3 thin films. Compared to a previously established carbazole-based hole-selective material (2-(3,6-dimethoxy-9H-carbazol-9-yl)ethyl)phosphonic acid (MeO−2PACz), the crystallinity of FAPbI3 is enhanced and the electronic defects are passivated by the PTZ−CPA more effectively, resulting in remarkable increases in photoluminescence quantum yield (four-fold) and Shockley-Read-Hall lifetime (eight-fold). Moreover, the PTZ−CPA shows a larger molecular dipole moment and improved energy level alignment with FAPbI3, benefiting the interfacial hole-collection. Consequently, FAPbI3-based inverted PSCs achieve an unprecedented efficiency of 25.35 % under simulated air mass 1.5 (AM1.5) sunlight. The PTZ−CPA based device shows commendable long-term stability, maintaining over 90 % of its initial efficiency after continuous operation at 40 °C for 2000 hours.  相似文献   

4.
We describe an efficient method for α-functionalization of N-aryl-tetrahydroisoquinolines under visible-light-irradiation catalyzed by organic photocatalyst. This protocol provides a concise and environmental approach for the rapid allylation and benzylation of N-aryl-tetrahydroisoquinolines, and shows broad substrate scope. Stable organoboron reagents have shown their ability in the construction of challenging Csp3−Csp3 bond. The load of the photocatalyst is low and the oxidant is inexpensive and less toxic.  相似文献   

5.
We describe a catalytic cascade sequence involving directed C(sp3)−H activation followed by β-heteroatom elimination to generate a PdII(π-alkene) intermediate that then undergoes redox-neutral annulation with an ambiphilic aryl halide to access 5- and 6-membered (hetero)cycles. Various alkyl C(sp3)−oxygen, nitrogen, and sulfur bonds can be selectively activated, and the annulation proceeds with high diastereoselectivity. The method enables modification of amino acids with good retention of enantiomeric excess, as well as σ-bond ring-opening/ring-closing transfiguration of low-strain heterocycles. Despite its mechanistic complexity, the method employs simple conditions and is operationally straightforward to perform.  相似文献   

6.
Directional organic transformation via a green, sustainable catalytic reaction has attracted a lot of attention. Herein, we report a photoelectrochemical approach for highly selective epoxidation of alkenes in a salt solution using Co2(OH)3Cl (CoOCl) as a bridge of photo-generated charge, where the lattice Cl of CoOCl can be oxidized to generate HClO by the photo-generated holes of BiVO4 photoanode and be spontaneously recovered by Cl of a salt solution, which then oxidizes the alkenes into the corresponding epoxides. As a result, a series of water-soluble alkenes, including 4-vinylbenzenesulfonic acid sodium, 2-methyl-2-propene-1-sulfonic acid sodium, and 3-methyl-3-buten-1-ol can be epoxidized with near 100 % conversion rate and selectivity. Through further inserting a MoOx protection layer between BiVO4 and CoOCl, the stability of CoOCl−MoOx/BiVO4 can be maintained for at least 120 hours. This work opens an avenue for solar-driven organic epoxidation with a possibility of on-site reaction around the abundant ocean.  相似文献   

7.
Introduction  Thesynthesisofmetal organicpolymershasundoubt edlybeenatopicofspecialinterestduetotheirhost guestinteractionswhichhavebeentailoredtoavarietyofindus trialprocessessuchascatalysis ,adsorptionandgassepa ration .1 5Sofar ,manyeffortshavebeendedicatedtotheexplorationofmetal organicframeworkmaterialsbuiltupfrommetallicclustersandrigidorganicbuildingblocks .Thisstrategy ,asreportedbythegroupsofRobson ,6Yaghi7 11andothers ,utilizesrigidorganiclinkersfordi rectlylinkingthemetalclusters…  相似文献   

8.
Synthesis and Crystal Structure of Complex of Zinc(Ⅱ)with Schiff Bas   总被引:2,自引:0,他引:2  
崔学桂  胡清萍 《结构化学》1994,13(5):340-342
  相似文献   

9.
TemplateSynthesisandStructureofDinuclearZincComplexwithThreeKindsofPyrazoleLigandsZHANGWen-Xing;MAChang-Qin;WANGXu-Ning;YUZhe...  相似文献   

10.
The brain-storm of designing low-cost and commercialized eutectic electrolytes for zinc (Zn)-based electrochemical energy storage (ZEES) remains unresolved and attractive, especially when implementing it at low temperatures. Here, we report an appealing layout of advancing chlorine-functionalized eutectic (Cl-FE) electrolytes via exploiting Cl anion-induced eutectic interaction with Zn acetate solutions. This novel eutectic liquid shows high affinity to collaborate with 1,3-dioxolane (DOL) and is prone to constitute Cl-FE/DOL-based electrolytes with a unique inner/outer eutectic solvation sheath for the better regulation of Zn-solvating neighboring and reconstruction of H-bonding. The side reactions are effectively restricted on Zn anodes and a high Coulombic efficiency of 99.5 % can be achieved over 1000 cycles at −20 °C with Zn//Cu setups. By prototyping scale-up Zn-ion pouch cells using the optimal eutectic liquid of 3ZnOAc1.2Cl1.8-DOL, we obtain improved electrochemical properties at −20 °C with a high capacitance of 203.9 F g−1 at 0.02 A g−1 in a range of 0.20–1.90 V and long-term cycling ability with 95.3 % capacitance retention at 0.2 A g−1 over 3,000 cycles. Overall, the proposal of ideal Cl-FE/DOL-based electrolytes guides the design of sub-zero and endurable aqueous ZEES devices and beyond.  相似文献   

11.
The hydrothermal reaction of ZnO with benzene‐1,4‐dicarboxylic add gave Zn·BDC·2H2O (1) and Zn‐BDC·H2O (2) (BDC = benzene‐1, 4‐dicarboxylate), respectively. Polymer 1 (C4H4O3ZH0.5) shows a one‐dimensional zigzag chain structure built up from the alternate connection of tetrahedral ZnO4 and BDC units. Polymer 2 (C4H3O2.5Zn0.5) possesses a three‐dimensional framework containing infinite zigzag Zn·Zn·Zn pseudochains generated by five‐coordinate zinc centers and a rectangular channel system including three groups of different straight channels along the [001], [010] and [60–1] directions. The two metal‐organic polymeric compounds exhibit strong photoluminescent emission bands at 402 nm (λex = 260 nm) (for 1) and at 344 nm and 385 nm (λex = 279 nm) (for 2) in the solid state at room temperature.  相似文献   

12.
Clusters combine the advantages of organic molecules and inorganic nanomaterials, which are promising alternatives for optoelectronic applications. Nonetheless, recently emerged cluster light-emitting diodes require further excited state optimization of cluster emitters, especially to reduce population of the cluster-centered triplet quenching state (3CC). Here we report that redox-active ligands enhance reverse intersystem crossing (RISC) of Cu4I4 cluster for triplet-to-singlet conversion, and thermally activated delayed fluorescence (TADF) host can provide an external RISC channel. It indicates that the complementarity between TADF host and cluster in RISC transitions gives rise to 100 % triplet conversion efficiency and complete singlet exciton convergence, rendering 100-fold increased singlet radiation rate constant and tenfold decreased triplet non-radiation rate constant. We achieve a photoluminescence quantum yield of 99 % and a record external quantum efficiency of 29.4 %.  相似文献   

13.
The aqueous electrocatalytic reduction of NO3 into NH3 (NitrRR) presents a sustainable route applicable to NH3 production and potentially energy storage. However, the NitrRR involves a directly eight-electron transfer process generally required a large overpotential (<−0.2 V versus reversible hydrogen electrode (vs. RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]-electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO2 and NH3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs. RHE). The high efficiency for such a reduction process was further explored in a zinc-nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L−1 at 10 mA cm−2 and a power density of 14.1 mW cm−2, which is well beyond all previously reported similar concepts.  相似文献   

14.
A novel coordination polymer {[Zn(ts-gln)(bipy)]3H2O}n (ts-glnH2=N-p-toly-sulfonyl-glutamine,bipy=2,2-bipyridine) has been prepared and structurally characterized by X-ray diffraction method. It crystallizes in orthorhombic,space group P212121 with a=8.2622(5),b=16.6244(10),c=18.2807(10) ,V=2510.9(3) 3,C22H28N4O8SZn,Mr=573.91,Z=4,Dc= 1.518 g/cm3,μ(MoKa)=1.115 mm-1,F(000)=1192,the final R=0.0262 and wR=0.0662 for 5691 independent reflections with Rint=0.0240. The zinc(Ⅱ) atom is coordinated by N(3) and N(4) atoms of a bipy molecule,two carboxylate O(1) and O(2A) and amino N(1) atoms of ts-gln ligands,resulting in a square-pyramidal geometry. The title complex consists of an infinite zigzag chain of zinc(Ⅱ) ions linked by the carboxylate of N-p-tolysulfonyl-glutamine.  相似文献   

15.
Aiming at extending the tagged zinc bipyrazolate metal–organic frameworks (MOFs) family, the ligand 3,3’-diamino-4,4’-bipyrazole ( 3,3’-H2L ) has been synthesized in good yield. The reaction with zinc(II) acetate hydrate led to the related MOF Zn(3,3’-L) . The compound is isostructural with its mono(amino) analogue Zn(BPZNH2) and with Zn(3,5-L) , its isomeric parent built with 3,5-diamino-4,4’-bipyrazole. The textural analysis has unveiled its micro-/mesoporous nature, with a BET area of 463 m2 g−1. Its CO2 adsorption capacity (17.4 wt. % CO2 at pCO2 = 1 bar and T = 298 K) and isosteric heat of adsorption (Qst = 24.8 kJ mol−1) are comparable to that of Zn(3,5-L) . Both Zn(3,3’-L) and Zn(3,5-L) have been tested as heterogeneous catalysts in the reaction of CO2 with the epoxides epichlorohydrin and epibromohydrin to give the corresponding cyclic carbonates at T = 393 K and pCO2 = 5 bar under solvent- and co-catalyst-free conditions. In general, the conversions recorded are higher than those found for Zn(BPZNH2), proving that the insertion of an extra amino tag in the pores is beneficial for the epoxidation catalysis. The best catalytic match has been observed for the Zn(3,5-L) /epichlorohydrin couple, with 64 % conversion and a TOF of 5.3 mmol(carbonate) (mmolZn)−1 h−1. To gain better insights on the MOF-epoxide interaction, the crystal structure of the [epibromohydrin@ Zn(3,3’-L) ] adduct has been solved, confirming the existence of Br⋅⋅⋅(H)−N non-bonding interactions. To our knowledge, this study represents the first structural determination of a [epibromohydrin@MOF] adduct.  相似文献   

16.
A novel coordination polymer {[Zn(ts-gln)(bipy)]3H2O}n (ts-glnH2=N-p-toly-sulfonyl-glutamine,bipy=2,2-bipyridine) has been prepared and structurally characterized by X-ray diffraction method. It crystallizes in orthorhombic,space group P212121 with a=8.2622(5),b=16.6244(10),c=18.2807(10) ,V=2510.9(3) 3,C22H28N4O8SZn,Mr=573.91,Z=4,Dc= 1.518 g/cm3,μ(MoKa)=1.115 mm-1,F(000)=1192,the final R=0.0262 and wR=0.0662 for 5691 independent reflections with Rint=0.0240. The zinc(Ⅱ) atom is coordinated by N(3) and N(4) atoms of a bipy molecule,two carboxylate O(1) and O(2A) and amino N(1) atoms of ts-gln ligands,resulting in a square-pyramidal geometry. The title complex consists of an infinite zigzag chain of zinc(Ⅱ) ions linked by the carboxylate of N-p-tolysulfonyl-glutamine.  相似文献   

17.
Non-fullerene all-small-molecule organic solar cells (NFSM-OSCs) have shown potential as OSCs, owing to their high purity, easy synthesis and good reproducibility. However, challenges in the modulation of phase separation morphology have limited their development. Herein, two novel small molecular donors, BTEC-1F and BTEC-2F, derived from the small molecule DCAO3TBDTT, are synthesized. Using Y6 as the acceptor, devices based on non-fluorinated DCAO3TBDTT showed an open circuit voltage (Voc) of 0.804 V and a power conversion efficiency (PCE) of 10.64 %. Mono-fluorinated BTEC-1F showed an increased Voc of 0.870 V and a PCE of 11.33 %. The fill factor (FF) of di-fluorinated BTEC-2F-based NFSM-OSC was improved to 72.35 % resulting in a PCE of 13.34 %, which is higher than that of BTEC-1F (61.35 %) and DCAO3TBDTT (60.95 %). To our knowledge, this is the highest PCE for NFSM-OSCs. BTEC-2F had a more compact molecular stacking and a lower crystallinity which enhanced phase separation and carrier transport.  相似文献   

18.
Two novel fluorene-based copolymers (PFSD and PFMD) containing squaric acid or maleimide unit in the main chain were synthesized in good yields by Suzuki coupling reaction. The resulting polymers possess excellent thermal stability, high electron affinity and high photolurninescence (PL) quantum yields. They can fluoresce in yellow-light range due to either the charge transfer between a fluorene segment and an electron-deficient containing squaric acid/maleimide segment of the polymers or the Forrster energy transfer between different polymer chains.The results from PL measurements of the isothermally heated polymer thin films show that the commonly observed aggregate excimer formation in polyfluorenes is very effectively suppressed in these two polymers due to the nonlinear structures of maleimide and squaric acid moieties. Double-layer polymer light-emitting diodes (PLED) were fabricated using the resulting polymers as the emitting layers and Ba or Mg:Ag(V:V=10:1) as cathodes.All the devices show bright yellow emission (562-579nm) with different maximum external quantum efficiencies (0.006%-1.13%). Compared with the other devices, indium-tin oxide (ITO)/polyethylenedioxythiophene (PEDOT):polystyrene sulfonic acid (PSS)/PFMD/Mg:Ag has the higher maximum external quantum efficiency of 1.13% at 564cd/m^2 with a bias of 8.4V.  相似文献   

19.
GOU Lei  LI Dong-Lin 《结构化学》2010,29(7):1098-1102
<正>The title compound,[Zn(4-pytpy)(NO_3)_2](4-pytpy=4'-(4-pyridyl)-2,2':6',2"- terpyridine)1,has been synthesized by the solvothermal reaction of Zn(NO_3)_2·6H_2O with 4-pytpy in CH_3OH solution.It crystallizes in the triclinic system,space group P_1~-with a=8.358(6),b= 11.121(8),c=11.374(8)(?),α=74.226(11),β=74.532(11),γ=83.085(12)°,M_r=499.74,V= 979.3(12)(?)~3,Z=2,D_c=1.695 g/cm~3,F(000)=508,μ=1.309 mm~(-1),the final R=0.0547 and wR= 0.1588.X-ray crystal structure analysis revealed that the Zn~Ⅱis hexa-coordinated by two oxygen atoms from two nitrate groups and four nitrogen atoms,three of which are from the tridentate domain of one 4-pytpy and the other from the monodentate domain of another 4-pytpy.4-pytpy as a bridging ligand connects Zn~Ⅱinto a one-dimensional coordination polymer.  相似文献   

20.
Cetyl-trimethylammoniumbromide(CTMAB)isaveryusefulcationicsurfactant,sothestudyondeterminationofCTMABassumesgreatimportance.AsmallamountofCTMABisgenerallydeterminedbyspectrophotometrybasingCTMABcombineswithtriazidetoformcoloredbinaryion-associationcomplex1-3.However,thosemethodsofdeterminationofCTMABhavedisadvantagesofsmalllinearrange,needofspecialreagent,determinationinbaseenvironment,etc.Inthispaper,indirectdeterminationofCTMABwithNaClandNH4SCNbyfloatationandseparationofZn(II…  相似文献   

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