Recent Advances in Mechanistic Understanding of Metal-Free Carbon Thermocatalysis and Electrocatalysis with Model Molecules

Metal-free carbon,as the most representative heterogeneous metal-free catalysts,have received considerable interests in electro-and thermo-catalytic reac-tions due to their impressive performance and sustainability.Over the past decade,well-designed carbon catalysts with tunable structures and heteroatom groups coupled with various characterization techniques have proposed numerous reaction mechanisms.However,active sites,key intermediate species,precise structure-activity relationships and dynamic evolution processes of carbon catalysts are still rife with controversies due to the monotony and limitation of used experimental methods.In this Review,we sum-marize the extensive efforts on model catalysts since the 2000s,particularly in the past decade,to overcome the influences of material and structure limitations in metal-free carbon catalysis.Using both nanomolecule model and bulk model,the real contribution of each alien species,defect and edge configuration to a series of fundamentally important reactions,such as thermocatalytic reactions,electrocatalytic reactions,were systematically studied.Combined with in situ techniques,isotope labeling and size control,the detailed reaction mechanisms,the precise 2D structure-activity relationships and the rate-determining steps were revealed at a molecular level.Furthermore,the outlook of model carbon catalysis has also been proposed in this work.

Deciphering the potassium storage phase conversion mechanism of phosphorus by combined solid-state NMR spectroscopy and density functional theory calculations

Phosphorus is the potential anode material for emerging potassium-ion batteries(PIBs)owing to the highest specific capacity and relatively low operation plateau.However,the reversible delivered capacities of phosphorus-based anodes,in reality,are far from the theoretical capacity corresponding to the formation of K3P alloy.And,their underlying potassium storage mechanisms remain poorly understood.To address this issue,for the first time,we perform high-resolution solid-state31P NMR combined with XRD measurements,and density functional theory calculations to yield a systemic quantitative understanding of(de)potassiation reaction mechanism of phosphorus anode.We explicitly reveal a previously unknown asymmetrical nanocrystalline-to-amorphous transition process via rP←→(K_(3)P_(11),K_(3)P_(7),beta-K_(4)P_(6))←→(alpha-K4P6)←→(K_(1-x)P,KP,K_(4-x)P3,K_(1+x)P)←→(amorphous K4P3,amorphous K3P)that are proceed along with the electrochemical potassiation/depotassiation processes.Additionally,the corresponding KP alloys intermediates,such as the amorphous phases of K_(4)P_(3),K_(3)P,and the nonstoichiometric phases of“K_(1-x)P”,“K_(1+x)P”,“K_(4-x)P_(3)”are experimentally detected,which indicating various complicated K-P alloy species are coexisted and evolved with the sluggish electrochemical reaction kinetics,resulting in lower capacity of phosphorus-based anodes.Our findings offer some insights into the specific multi-phase evolution mechanism of alloying anodes that may be generally involved in conversion-type electrode materials for PIBs.

Locating the cocktail and scaling-relation breaking effects of high-entropy alloy catalysts on the electrocatalytic volcano plot

High entropy alloys(HEAs)have been the star materials in electrocatalysis research in recent years.One of their key features is the greatly increased multiplicity of active sites compared to conventional catalytic materials.This increased multiplicity stimulates a cocktail effect and a scaling-relation breaking effect,and results in improved activity.However,the multiplicity of active sites in HEAs also poses new problems for mechanistic studies.One apparent problem is the inapplicability to HEA catalysts of the currently most popular mechanistic study method,which uses the electrocatalytic theoretical framework(ETF)based on the computational hydrogen electrode(CHE).The ETF uses a single adsorption energy to represent the catalyst,i.e.,a catalyst is represented by a'point'in the volcanic relationship.It naturally does not involve the multiplicity of active sites of a catalyst,and hence loses brevity in expressing the cocktail effect and scaling-relation breaking effect in HEA catalysis.This paper attempts to solve this inapplicability.Based on the fact that the adsorption energy distribution of HEAs is close to a normal distribution,the mean and variance of the adsorption energy distribution are introduced as descriptors of the ETF,replacing the original single adsorption energy.A quantitative relationship between the variance and the cocktail and scaling-relation braking effects is established.We believe the method described in this work will make the ETF more effective in mechanistic studies of HEA electrocatalysis.

Anion Defects Engineering of Ternary Nb-Based Chalcogenide Anodes Toward High-Performance Sodium-Based Dual-Ion Batteries

Sodium-based dual-ion batteries(SDIBs) have gained tremendous attention due to their virtues of high operating voltage and low cost, yet it remains a tough challenge for the development of ideal anode material of SDIBs featuring with high kinetics and long durability. Herein, we report the design and fabrication of N-doped carbon film-modified niobium sulfur–selenium(NbSSe/NC) nanosheets architecture, which holds favorable merits for Na^(+) storage of enlarged interlayer space, improved electrical conductivity, as well as enhanced reaction reversibility, endowing it with high capacity, high-rate capability and high cycling stability. The combined electrochemical studies with density functional theory calculation reveal that the enriched defects in such nanosheets architecture can benefit for facilitating charge transfer and Na+ adsorption to speed the electrochemical kinetics. The NbSSe/NC composites are studied as the anode of a full SDIBs by pairing the expanded graphite as cathode, which shows an impressively cyclic durability with negligible capacity attenuation over 1000 cycles at 0.5 A g^(-1), as well as an outstanding energy density of 230.6 Wh kg^(-1) based on the total mass of anode and cathode.

Self-assembled Nanohybrid from Opposite Charged Sheets:Alternate Stacking of CoAl LDH and MoS2

Hybrid materials are attracting intensive attention for their applications in electronics, photoelectronics, LEDs, field-effect transistors, etc. Engineering new hybrid materials and further exploiting their new functions will be significant for future science and technique development. In this work, alternatively stacked self-assembled CoAl LDH/MoS2 nanohybrid has been successfully synthesized by an exfoliation-flocculation method from positively charged CoAl LDH nanosheets（CoAl-NS） with negatively charged MoS2 nanosheets（MoS2-NS）. The CoAl LDH/MoS2 hybrid material exhibits an enhanced catalytic performance for oxygen evolution reaction（OER） compared with original constituents of CoAl LDH nanosheets and MoS2 nanosheets. The enhanced OER catalytic performance of CoAl LDH/MoS2 is demonstrated to be due to the improved electron transfer, more exposed catalytic active sites, and accelerated oxygen evolution reaction kinetics.

Synthesis,Crystal Structure and Photoluminescence of a Dinulear Copper Complex

A binuclear cuprous complex [Cu（μ-I）（NPPh）]2（1,NPPh = 1-（2-（diphenylphosphanyl）phenyl）-3-phenyl-4,5-dihydro-1 H-pyrazole） was synthesized and characterized by elemental analysis,NMR and X-ray single-crystal structure analysis.It crystallizes in triclinic space group P2_1/n with a = 10.7520（3）,b = 18.1860（5）,c = 11.8487（3） ？,β = 91.864（2）,V = 2315.61（11） ？~3,Z = 4,Mr = 594.87,Dc = 1.706 g/cm^3,F（000） = 1176.0,μ = 12.582 mm（-1）,GOOF = 1.048,the final R = 0.0289 and wR = 0.0670 for 3787 observed reflections with I 〉 2σ（I）.The Cu atoms in the complex are four-coordinated and adopt distorted tetrahedral coordination geometry.In the solid state,the complex exhibits greenish yellow photoluminescence with a peak maximum of 533 nm,a decay time of 34 μs,and a photoluminescence quantum yield of 63.6% at room temperature,respectively.

Influence of different Fe doping strategies on modulating active sites and oxygen reduction reaction performance of Fe, N-doped carbonaceous catalysts

Fe/N/C catalysts,synthesized through the pyrolysis of Fe-doped metal–organic framework (MOF) precursors,have attracted extensive attention owing to their promising oxygen reduction reaction (ORR) catalytic activity in fuel cells and/or metal-air batteries.However,post-treatments (acid washing,second pyrolysis,and so on) are unavoidable to improve ORR catalytic activity and stability.The method for introducing Fe^(3+) sources (anhydrous Fe Cl_(3)) into the MOF structure,in particular,is a critical step that can avoid time-consuming post-treatments and result in more exposed Fe-N_(x) active sites.Herein,three different Fe doping strategies were systematically investigated to explore their influence on the types of active sites formed and ORR performance.Fe-NC(Zn^(2+)),synthesized by one-step pyrolysis of Fe doped ZIF-8 (Zn^(2+)) precursor which was obtained by adding the anhydrous Fe Cl_(3)source into the Zn(NO_(3))_(2)·6H_(2)O/methanol solution before mixing,possessed the highest Fe-N_(x)active sites due to the high-efficiency substitution of Zn^(2+)ions with Fe^(3+) ions during ZIF-8 growth,the strong interaction between Fe^(3+) ions and N atoms of 2-Methylimidazole (2-MIm),and ZIF-8’s micropore confinement effect.As a result,Fe-NC(Zn^(2+)) presented high ORR activity in the entire p H range (p H=1,7,and 13).At p H=13,Fe-NC(Zn^(2+)) exhibited a half-wave potential (E1/2) of 0.95 V (vs.reversible hydrogen electrode),which was 70 m V higher than that of commercial Pt/C.More importantly,Fe-NC(Zn^(2+)) showed superior ORR stability in neutral media without performance loss after 5,000 cycles.A record-high open-circuit voltage(1.9 V) was obtained when Fe-NC(Zn^(2+)) was used as a cathodic catalyst in assembled Mg-air batteries in neutral media.The assembled liquid and all-solid Mg-air batteries with high performance indicated that Fe-NC(Zn^(2+)) has enormous potential for use in flexible and wearable Mg-air batteries.

Synthesis,Crystal Structure and Photoluminescence of a Cuprous Dimer with Tetrakis(pyrazol-i-yl)borate Linker

A cuprous dimer [Cu（POP）]2（pz4B）BF4·（CH3CN）3 （1, POP = bis（2-（diphenylphosphanyl）phenyl）ether, pz4B- = tetrakis（pyrazol-i-yl）borate anion） was synthesized from the reaction of Cu（CH3CN）4BF4, POP and Kpz4B in CH3CN at room temperature. The compound was characterized by elemental analysis and X-ray single-Crystal structure analysis. It crystallizes in monoclinic, space group P21/c with a = 12.3491（2）, b = 20.8845（3）, c = 33.0657（4） A, β = 94.251（1）°, V = 8504.3（2） A3, Z = 4, Mr = 1693.21, Dc = 1.322 g/cm3, F（000） = 3496,μ = 1.843 mm-1, GOOF = 1.031, the final R = 0.0442 and wR = 0.1235 for 14397 observed reflections with 1〉 2σ（I）. 1 is an ionic compound. It is composed of a BF4- anion and a {[Cu（POP）]2（pz4B）}＋ cation. The cation contains two [Cu（POP）]＋ cationic moieties and a pz4B- anionic linker. The Cu（I） ions show a distorted tetrahedral coordination geometry defined by two nitrogen atoms from a pz4B- bridging ligand and two phosphorous atoms from a POP terminal chelating ligand. The complex emits blue luminescence with the maximum peak at 457 nm with 3% quantum yield in solid state at room temperature. The Cu（I） centers are essentially electronically separated because both HOMO and LUMO contain very little contribution from the bridging ligand. The unexpected low emission is ascribed to the intramolecular interaction of the emissive centers.

Understanding De-protonation Induced Formation of Spinel Phase in Li-rich Layered Oxides for Improved Rate Performance

Constructing layered-spinel composites is important to improve the rate performance of lithium-rich layered oxides.However,up to now,the effect of microstructure of composites on the rate performance has not been well investigated.In this study,a series of samples were prepared by a simple protonation and de-protonation for the pristine layered material(LiMnNiCoO)obtained by sol-gel method.The characterizations of XRD,Raman and oxidation-reduction potentials of charge-discharge curves demonstrated that these samples after de-protonation are layered-spinel composites.When these composites were tested as a cathode of lithium-ion batteries,the sample treated with 0.1 M of nitric acid exhibited higher discharge capacities at each current density than that of other composites.The outstanding rate performance is attributed to the high concentration of conduction electron resulting from the low average valence state(44.2%of Ni)as confirmed by its high conductivity(1.124×10??mat39800Hz)and ambient temperature magnetic susceptibility(8.40×10emu/Oe?mol).This work has a guiding significance for the synthesis of high rate performance of lithium battery cathode materials.

Synthesis, Structure and Electrocatalytic Activity of Perfluorinated Covalent Triazine-based Framework

Using the bottom-up method, we synthesized a series of perfluorinated covalent triazine-based frameworks(FCTFs) with porous structures for catalysis oxygen reduction reaction(ORR). The evolved FCTFs by high-temperature carbonization show an apparent variation in electrocatalytic activity toward the ORR dependent on the type of F. The samples synthesized at 900 ℃(FCTF-900) exhibits advantages in terms of high activity, high durability, and methanol-tolerant as an efficient electrocatalyst for ORR, manifests a comparable or even better activity as compared with the commercial Pt/C catalysts not only in alkaline media but also in acidic and neutral electrolyte.

Tri-profit electrolysis for energy-efficient production of benzoic acid and H_(2)

Electrosynthesis has recently attracted intensive research attentions and holds great potential in implementing scalable green synthesis thanks to more and more readily accessible renewable electric energy.

Synthesis and Crystal Structure of a Cobalt(Ⅱ)Complex Based on 2,2-Bibenzimidazole and N,N-bis(phosphonomethyl)aminoacetic Acid

The title complex, [Co2（bibzim）（H2bibzim）4]·Co2（H2bibzim）2（Hbibzim）（HL）]2- 2H2O （1） （HEbibzim = 2,2＇-bibenzimidazole, H5L = N,N-bis（phosphonomethyl）aminoacetic acid （HO2CCH2N（CH2PO3H2）2））, was synthesized with hydrothermal reactions. The compound crystallizes in triclinic, space group P1 with a = 13.71020（10）, b = 14.9165（5）, c = 20.9924（5） A, a = 86.344（9）, β = 71.214（8）, γ = 73.757（7）°, C162HI24Co6N46O18P4, Mr = 3478.52, V = 3900.55（16） A3, Z = 2, Dc = 1.482 g/cm3,μ（MoKa） = 0.747 mm^-1, F（000） = 1784, the final R = 0.0777 and wR = 0.2091 for 13598 observed reflections （I 〉 2σ（I））. X-ray diffraction analysis reveals that there are three crystallographically independent Co（II） atoms in the complex. The complex consists of binuclear coordination cation, binuclear coordination anion, as well as lattice water molecules, which further aggregate into a 3D framework via hydrogen bonding as well as π-π interactions.

Synthesis of 3D Porous and Interconnected Hollow Carbon Nanospheres Array and Its Applications in Lithium-sulfur Batteries

Lithium-sulfur（Li–S） batteries are receiving much attention due to their high theoretical lithium storage capacity and energy density. However, the commercialization of Li–S batteries is mainly impeded by the inherent poor electrical conductivity of sulfur, the side shuttle behavior of polysulfides, and the volumetric change of sulfur during cycles. To solve these problems, here we report a unique 3D porous and interconnected hollow carbon nanospheres array（3D-HCNA） as sulfur host for lithium-sulfur batteries. This 3D-HCNA was synthesized through a nanocasting approach with sucrose as carbon precursors and mesoporous silica nanospheres as hard-templates. The silica nanospheres with special nanostructure were obtained by a biphase stratification approach. Owing to its unique architecture, as-prepared 3D-HCNA/S cathode with a high sulfur loading of 76 wt% exhibited excellent electrochemical performance. It showed highinitial capacity of 1318 m Ah/g at 0.05 C and good rate capability of 760 m Ah/g at 1 C. Moreover, excellent cycling performance was also observed with a capacity of 757 m Ah/g maintained after 200 cycles at 0.5 C.

Synthesis,Crystal Structure and Photophysical Property of 2-(9H-carbazol-9-yl)-3-(2-(2,4,5-tri-(9H-carbazol-9-yl)-3,6-dicyanophenoxy)phenoxy)dibenzo[b,e][1,4]dioxine-1,4-dicarbonitrile

A purely organic compound 2-（9 H-carbazol-9-yl）-3-（2-（2,4,5-tri-（9 H-carbazol-9-yl）-3,6-dicyanophenoxy）phenoxy）dibenzo[b,e][1,4]dioxine-1,4-dicarbonitrile, C76 H40 N8 O4, was synthesized and characterized by NMR, UV-Vis, photoluminescenceand X-ray single-crystal structure analysis. The compound crystallizes in monoclinic system, space group P21/n with a = 11.6537（3）, b = 34.9738（8）, c = 15.5053（3） ？, β =101.992（2）°, V = 6181.6（2）？3, Z = 4, Mr= 1129.18 g/mol, Dc =1.396 g/cm3, F（000） =2672, μ = 2.239 mm–1, GOOF = 1.019, the final R = 0.0577 and wR= 0.1559 for 11925 observed reflections with I 〉2σ（I）. The UV-vis absorption and fluorescence of the compound were discussed. The compound exhibitsyellow-green luminescence with maximum emission peak at 538 nm, and quantum yields of ф = 0.25 and 0.48 in air-equilibrated and degassed toluene at room temperature. Transient decay spectral studies show that compound 1 displays two component decay fashions with a short decay lifetime of 23 ns for the prompt fluoresce anda long decay lifetime of 3.8ms for thermally activated delayed fluorescence. In air-equilibrated toluene, only a short decay lifetime of 17 ns was observed.The experimental and computational results show thatthe emission of the compound originates from the CT excited states.

Approaching Superior Potassium Storage of Carbonaceous Anode Through a Combined Strategy of Carbon Hybridization and Sulfur Doping

Carbonaceous materials are promising anode candidates for potassium-ion batteries(PIBs)given its high conductivity,stable property,and abundant resource,while its practical implementation is still hampered by its limited capacity and inferior rate behavior.Herein,we report a superior carbonaceous anode through a combined strategy of carbon hybridization and heteroatom doping.In this composite,hollow carbon spindles(HCS)were anchored on the surface of graphene(G)followed with sulfur doping treatment,aiming to integrate the high conductivity of graphene,the good structure stability of HCS,and the S doping-induced ample active sites.As a PIB anode,the S-G@HCS composite can display high capacity(301 mAh g^(-1)at 0.1 A g^(-1)after 500 cycles)and long-term cyclability up to 1800 cycles at 2 A g^(-1).Impressively,it can deliver an outstanding rate capacity of 215 mAh g^(-1)at 10 A g^(-1),which is superior to most carbon anodes as-reported so far for PIBs.Experimental and theoretical analysis manifests that the construction of graphene/amorphous carbon interface as well as S doping enables the regulation of electronic structure and ion adsorption/transportation properties of carbonaceous material,thus accounting for the high capacity and superior rate capability of S-G@HCS composite.

Synthesis,Crystal Structure and Photoluminescence of a TADF Cuprous Complex

A four-coordinate mononuclear cuprous complex oCBP-Cu-Pym(1, oCBP =1,2-bis(diphenylphosphine)-nido-carborane, Pym = 2-methyl-6-(1 H-pyrazol-1-yl)pyridine) was synthe-sized and characterized by elemental analysis, NMR, UV-Vis and X-ray single-crystal structure analysis. It crystallizes in monoclinic space group C2/c with a = 28.4182(8), b =16.2994(4), c = 22.2708(5) ?, β = 127.219(2)°, V = 8214.8(3) ?3, Z = 8, Mr = 766.92, ρcalc = 1.24 g/cm3, F(000) = 3160, μ = 2.30 mm–1, GOOF = 1.063, the final R = 0.0700 and wR = 0.1903 for7158 observed reflections with I > 2σ(I). The Cu(I) ion adopts a highly distorted tetrahedral geometry defined by two nitrogen and two phosphorous atoms. Under UV 365 nm at room temperature, this complex exhibits green emission with maximum emission peak at 516 nm,lifetime 32.4 μs and quantum yield(ф = 0.461) in the solid state. Photophysical investigation suggests that the emission of complex 1 at room temperature was attributed to TADF, which is strongly supported by theoretic calculation.

Fabrication of WO3/TiO2 Heterostructures for Efficiently Photocatalytic Gaseous Hydrocarbons Degradation:Origin of Photoactivity and Revisit the Role of WO3 Decoration

Efficient oxidation of gaseous small molecular hydrocarbons under mild conditions remains a significant but challenging task to date. Here we report that WO3 decoration can obviously improve the performance of TiO2 （P25） toward the photocatalytic oxidation of several small molecular hydrocarbons （C2H6, C3H8 and C2H4） under simulated solar light irradiation. Among the WO3/TiO2 heterostructures, the 10wt%WO3/TiO2 nanocomposite shows the best photoactivities, which can efficiently oxidize C2H6, C3H8 and C2H4 within 15, 9 and 8 minutes, respectively under simulated sunlight with a light intensity of 200 mW/cm2. By strong contrast, a decreased photoactivity of TiO2 by coupling with WO3 is observed when investigating the performance of photocatalysts toward the degradation of methylene blue （MB） in liquid phase. The opposing effect of WO3 decoration on the performance of TiO2 is thoroughly investigated, and it is found that the improved photoactivities for gaseous hydrocarbon degradation is ascribed to the enhanced oxygen adsorption, resulting from WO3 decoration rather than efficient charge separation within the WO3/TiO2 heterostructures.

Synthesis and Characterization of a Water-stable Metal-organic Framework Based on Mixed Ligands

A new water-stable metal-organic framework,[Cu_2（bdc）_2（tpt）_3]·2H_2O（1,H_2 bdc = terephthalic acid,tpt = 2,4,6-tri（4-pyridinyl）-1,3,5-triazine）,has been synthesized and characterized by elemental analysis,infrared（IR） spectrum,thermogravimetric analysis（TGA）,powder X-ray diffraction（PXRD） and single-crystal X-ray diffraction. Compund 1 crystalizes in monoclinic,space group C2/c with a = 30.147（5）,b = 11.0548（17）,c = 20.867（4） ？,β = 115.035（2）o,C_（70）H_（48）Cu_2N_（18）O_（10）,Mr = 1428.34,V = 6301.0（18） ？~3,Z = 8,D_c = 1.506 g/cm^3,μ = 0.754 mm^（–1）,F（000） = 2928,GOOF = 1.058,λ（MoK α） = 0.71073 ？,the final R = 0.0387 and wR = 0.1091 for 6230 observed reflections with I 〉 2σ（I）. In compound 1,the half metallacycles [Cu_2（tpt）_3] are linked by the bdc2-ligands to form a 1D bent ladder-like chain featured with a nano-sized channel,and these chains link each other via intermolecular hydrogen bonds and π-π stacking interactions to form a 3D supramolecular architecture with the voids filled with free water molecules. In addition,the water stability of 1 was investigated by PXRD patterns,which indicate that compound 1 keeps its structural integrity in boiling water for at least three days.

Synthesis,Crystal Structure,and Photo-and Electro-luminescence of a TADF Cu(Ⅰ)Complex

A four-coordinate mononuclear cuprous complex [Cu（ac1m）POP]BF4·0.5（C6H14）· 0.5（C2H5OH）（1, ac1 m = 2-（2-ethoxyphenyl）-1-phenyl-1H-imidazo[4,5-f][1,10]phenanthroline, POP = bis[2-（dipenylphosphino）phenyl]ether） was synthesized and characterized by elemental analysis, NMR, UV-vis, cyclic voltammetry and X-ray single-crystal structure analysis. It crystallizes in monoclinic space group P21/c with a = 17.0546（19）, b = 15.4650（17）, c = 23.685（2） A, β = 104.007（11）°, V = 6061.1（12）A^3, Z = 4, Mr = 1171.46, Dc = 1.284 g/cm^3, F（000） = 2432, μ = 1.50 mm^–1, GOOF = 1.070, the final R = 0.059 and wR = 0.1640 for 8952 observed reflections with I 〉 2σ（Ⅰ）. Compound 1 is composed of a BF4-anion and a [Cu（ac1m）POP]^＋ cation. The Cu（Ⅰ） ion adopts a tetrahedral coordination geometry defined by two nitrogen and two phosphorous atoms. The complex exhibits yellow luminescence with maximum emission peaks at 546 nm, lifetimes 15.1 μs and quantum yields（ф = 0.130） at room temperature. The complex displays thermally activated delayed fluorescence（TADF） at room temperature, which is proved experimentally and theoretically. And the organic light-emitting diode（OLED） with 1 as the light emitting material has the maximum current efficiency of 5.86 cd/A and the highest brightness of 3215 cd/m^2.

Synthesis and Characterization of a Novel Coordination Complex Based on Fluorescein

A novel coordination complex,{[Cd）2（C（20）H（10）O5）2（H2O）4]·10H2O}n,has been synthesized based on fluorescein（2-（6-hydroxy-3-oxo-3 H-xanthen-9-yl） benzoic acid） and systematically characterized by elemental analysis,infrared（IR） spectrum,thermo gravimetric analysis（TGA）,powder X-ray diffraction（PXRD） and single-crystal X-ray diffraction.Compound 1 crystallizes in monoclinic,space group P2/n with a = 20.428（5）,b = 8.084（2）,c = 21.689（5）A,β = 96.360（5）°,Mr = 993.46,V = 3559.7（15）A^3,Z = 4,Dx = 1.845 g/cm^3,μ = 1.276 mm^-1,F（000） = 1974,GOOF = 1.044,λ（Mo Kα） = 0.71073 ？,the final R = 0.0553 and wR = 0.1720 for 7245 observed reflections with I 〉 2σ（I）.