Highly safe and ionothermal synthesis of Ti3C2 MXene with expanded interlayer spacing for enhanced lithium storage

MXene is a rising star of two-dimensional(2D)materials for energy relative applications,however,the traditional synthesis of MXene etched by hazard HF acid or LiF+HCl mixed solution is highly dangerous with the risk of splashing or pouring liquid solutions.In this work,we developed a water-free ionothermal synthesis of 2D Ti3C2 MXene via etching pristine Ti3AlC2 MAX in low-cost choline chloride and oxalic acid based deep eutectic solvents(DES)with the presence of NH4F,thus it was highly safe and convenient to operate solid precursor and product materials at room temperature.Benefited from the low vapor pressure and solvating properties of DES,the prepared Ti3C2(denoted as DES-Ti3C2)possessed a high purity up to 98% compared with 95% for HF etched Ti3C2(denoted as HF-Ti3C2).Notably,an expanded interlayer spacing of 1.35 nm could be achieved due to the intercalation of choline cations in DES-Ti3C2,larger than that of HF-Ti3C2(0.98 nm).As a result,the DES-Ti3C2 anodes exhibited enhanced lithium storage performance,such as high reversible capacity of 208 m Ah g-1at 0.5 A g-1,and long cycle life over 400 times,outperforming most reported pure MXene anodes.The ionothermal synthesis of MXene developed here may pave a new way to safely prepare other MXene for various energy relating applications.

Ionothermal Synthesis, Crystal Structure and Antibacterial Activities of a New 3d-4f Hetero-metallic Compound Containing Two Kinds of Ligands

A new 3d-4f（CuⅡ-CeⅢ） hetero-metallic compound containing two kinds of ligands, namely [CuⅡ（H2pdc）（phen）（H2O）]（HⅢ3O）2[CeⅢ（pdc）3][CuⅡ（phen）Ce（pdc）3]（1, H2 pdc = pyridine-2,6-dicarboxylic acid, phen = 1,10-phenanthroline）, has been synthesized by an ionothermal method using the ionic liquid 3-butyl-1-methylimidazolium bromide（[Bmim]Br） as solvent, and characterized by elemental analysis, energy-dispersive X-ray spectroscopy（EDS）, IR, XPS and single-crystal X-ray diffraction. The structure reveals that 1 belongs to the triclinic system, space group P1 with a = 12.044（7）, b = 14.841（8）, c = 22.305（13） A, α = 85.802（12）, β = 85.471（12）, γ = 89.174（11）°, Z = 2, V = 3964（4） A3, Dc = 1.804 g·cm-3, F（000） = 2140, μ = 1.757 mm-1, the final R = 0.0734, wR = 0.1094 and S = 1.013. The compound can be viewed as a two-dimensional layered structure composed by 3d-4f hetero-nuclear anions [Cu（phen）Ce（pdc）3]-, coordination cations [Cu（H2pdc）（phen）（H2O）]2＋, coordination anions [Ce（pdc）3]3- and protonated water molecules via hydrogen bonding interactions and π-π stacking. Moreover, the antimicrobial activities of 1 have been also investigated. The results indicated that its inhibitory activity is slightly higher than that of penicillin against Candida albicans.

Ionothermal Synthesis,Structure and Luminescent Properties of a New 2-D Bismuth(Ⅲ) Coordination Polymer with(6,5)-Connected Topological Sheet

A new 2-D Bi（3＋） coordination polymer {Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2}n（1,C7H3NO4 = pyridine-2,6-dicarboxylate） containing（6,5）-connected topological sheet with the Schl？fli symbol of（4~4·6~3·8~4·12~4）（4~5·6~4·8） has been synthesized by an ionothermal method using the ionic liquid 1-ethyl-3-methylimidazolium bromide（[Emim]Br） as solvent,and characterized by C,H and N elemental analysis,energy-dispersive X-ray spectroscopy（EDS）,infrared spectrum（IR spectrum） and single-crystal X-ray diffraction.The results indicate that 1 belongs to the monoclinic system,space group P21/n with a = 13.766（7）,b = 4.142（2）,c = 16.439（8） ？,β = 99.099（9）°,Z = 2,V = 925.6（8） ？~3,Dc = 4.414 g·cm^（-3）,F（000） = 1064,μ = 37.985 mm-1,the final R = 0.0326,wR = 0.0727 and S = 1.022.The molecular structural units [Bi4（μ3-O）2（μ4-O）2（C7H3NO4）2] are connected to each other via bridging O atoms,extending into an interesting 2-D layered structure.These resulting layers are further assembled by weak C-H…O hydrogen bonds into a 3-D supramolecular architecture.Moreover,its thermal stability and the luminescent properties have been also studied.

Rapid Microwave-Assisted Ionothermal Dissolution of Cellulose and Its Regeneration Properties

Introduction of the strategy of anhydrous calcium carbonate protection incorporated with the drop by drop reaction,high-purity 1-butyl-3-methylimidazolium chloride([Bmim]Cl)was prepared at reaction temperature of 80°C for only 10 h.Cellulose samples from different biomass sources(with different degree of polymerization characteristic)could be rapidly(no more than 10 minutes)and completely dissolved in the[Bmim]Cl using a microwave-assisted ionothermal route.Homogeneous cellulosic regenerates with high degree of polymerization and thermal stability characteristics were obtained through a coagulation process in water.Furthermore,the dissolved celluloses were readily regenerated into solid products such as casting films and spinning fibers,which exhibited high transparency and flexibility,as well as superior mechanical properties of over 300 MPa(tensile strength)more than those of cellulose samples reported.This study therefore provides a new process for the synthesis of high-purity[Bmim]Cl for the highly efficient dissolution of cellulose to produce high performance cellulosic materials for various applications such as flexible electronic,optoelectronic,soft robots.

Ionothermal Synthesis and Characterization of a Threedimensional Anionic Zinc-5-sulfoisophthalate Framework Charge-balanced with the 1-Ethyl-3-methylimidazolium

The ionothermal reaction of Zn（NO3）2·6H2O with 5-sulfoisophthalic acid monosodium salt（NaH2SIP） and 1,2,4-triazole in 1-ethyl-3-methylimidazolium tetrafluoroborate（EMIM-BF4） ionic liquid has afforded the compound {（EMIM）[Zn（SIP）]}n（1）.The Zn（Ⅱ） ions are linked by the carboxylate groups of SIP^3- ligands to give a two-dimensional layered structure featuring the centrosymmetric dinuclear Zn2（μ2-COO）2 units.The adjacent two-dimensional layers are further linked by the Zn-0 bonds between the Zn（Ⅱ） ions and the sulfonate O atoms to generate a three-dimensional anionic[Zn（SIP）]n^n- framework featuring one-dimensional open channels propagating along the a axis.The imidazolium cations[EMIM]^＋ derived from ionic liquid act as extraframework charge-balancing species for the anionic[Zn（SIP）]n^n- framework and occupy the void space of the one-dimensional open channels.The rich ionic environments of the ionic liquid may be particularly helpful in the formation of the ionic compound 1.The roles of the ionic liquid in ionothermal synthesis and crystallization of the compound are briefly discussed.Furthermore,compound 1 displays a photoluminescent emission at 490 nm upon excitation at 406 nm.

In situ Ionothermal Synthesis and Characterization of a Novel Cuprous Halide Complex

A new compound [mpba][Cu_2Br_3]（1, mpba = 4-（N-methylpyridin-4-yl）benzoic acid） has been ionothermally synthesized and characterized by single-crystal X-ray diffraction analysis, infrared spectrum, elemental analyses, fluorescence spectrum, and thermogravimetric analysis. In compound 1, the [mpba]＋ cation is a new organic template, which is obtained firstly in this work by in situ alkylation reaction of N-heterocycles 4-（pyridin-4-yl）benzoic acid with [Emim]Br（Emim = 1-ethyl-3-methyl imidazolium）. Hirshfeld surface analysis shows that weak interactions between the [mpba]＋ cations and 1D inorganic [Cu_2Br_3]~– are mainly C–H···Br hydrogen bonds. In addition, a pairwise O–H···O interaction is observed between the adjacent [mpba]＋cations. These different types of weak interactions make compound 1 stable up to 300 ℃. Fluorescence spectrum investigation shows 1 has a strong yellow emission at 555 nm. Theoretical calculation not only demonstrates compound 1 is a wild band semiconductor with a 3.3 e V band gap but also elucidates the fluorescence emission derives from the p-π＊ transition of electrons from [Cu_2Br_3]~– to [mpba]~＋.

Ionothermal Synthesis and Fluorescence Property of a Complex Constructed by Seven Nuclear(CH_3COO)_2Co_7(OH)_2] Clusters and 4,4＇-Oxybisbenzoic Acid Ligand

A new 3D cobalt metal-organic framework [C_7H_（13）N_2]_2[（CH_3COO）_2Co_7（oba）_5-（Hoba）_2（OH）_2]·H_2O has been synthesized under ionothermal conditions and characterized by elemental analysis, FT-IR, XRD, and TG. This complex crystallizes in monoclinic system, space group P21/c with a = 19.4499（4）, b = 10.8839（2）, c = 27.7796（5） ？, β = 104.467（2）o, V = 5694.22（19） ？~3, Z = 2, C_（116）H_（92）Co_7N_4O_（42）, M_r = 2626.45, D_c = 1.532 g/cm^3 , F（000） = 2682, μ = 1.085 mm-1, R = 0.0387 and wR = 0.1177. Its structure is characterized as a 3D open framework constructed by seven nuclear clusters [（CH_3COO）_Co_7（OH）_2] and the 4,4？-oxybisbenzoic acid ligand. The used ILs cations are located in the middle of the pore and compensate for the negative charges of framework. Furthermore, its fluorescence property has also been studied.

Ionothermal Synthesis and Phase Transformation of Organic-inorganic Hybrid Neutral Zincophosphate Cluster [Zn(HPO_4)(H_2PO_4)][C_6H_(10)N_3O_2]

Ionothermal synthesis was used to prepare a novel amino acid containing hybrid zincophosphate monomer,[Zn（HPO4）（H2PO4）][C6H10N3O2]（denoted as ZnPO-CJ58）.The inorganic framework of [Zn（HPO4）（H2PO4）]·[C6H10N3O2] consists of 4-membered rings formed by ZnO3OHis and PO2（OH）2 tetrahedra.The HPO4 and amino acid moieties hang on the Zn center.Such a framework is stabilized by extensive multipoint hydrogen bonds involving the phosphate units and histidine molecules to form a pseudo-3D supramolecular structure.It is noteworthy that ZnPO-CJ58 is the first zinc phosphate cluster with amino acid acting as the ligand.It exhibits photoluminescence excited at a wavelength of 220 nm.Interestingly,ZnPO-CJ58 can transform into a layered structure （C6H10N3O2）Zn2·（HPO4）（PO4）·H2O（ZnPO-CJ36） through further reacting with water or zinc acetate dihydrate in water at 85℃ for 1 h.This work will be helpful for the synthesis of crystalline inorganic-organic hybrid materials with biofunctional molecules.

Ionothermal Synthesis and Characterization of a New Selenidomercurate

A new selenidomercurate compound, namely(bmmim)2Hg(Se4)2(1, bmmim = 1-butyl-2,3-dimethylimidazolium), has been ionothermally synthesized by the reaction of HgSe, Sb and Se in a mixed solvent of the ionic liquid of(bmmim)Cl and methylamine aqueous solution. The(bmmim)Cl acted as an efficient structure-directing agent(SDA) and reactive solvent in the formation of 1. Single-crystal X-ray diffraction study reveals that 1 crystallizes in the monoclinic space group C2/c with a = 17.9540(10), b = 10.8863(5), c = 16.4728(9)?, β = 110.024(2)°, V = 3025.0(3) ?3, Z = 4, D-1 c = 2.500 mg·m-3, F(000) = 2088, μ = 14.729 mm, R = 0.0186 and wR = 0.0503(I > 2σ(I)). The structure of compound 1 features a bamboo dragonfly-like anion unit of [Hg(Se4)2]2-in which the Hg atom binds to two(Se4)2-groups to form two five-membered rings. The thermal stability and optical property of compound 1 were also investigated.

Ionothermal Syntheses and Crystal Structures of Two Cobalt(Ⅱ) Compounds:Co(2,2'-bpy)_2Br_2 and Co(1,10-phen)_2Br_2

Two cobalt（Ⅱ） compounds,Co（2,2-bpy） 2 Br 2 （1,2,2-bpy=2,2-bipyridyl） and Co（1,10-phen） 2 Br 2 （2,1,10-phen=1,10-phenanthroline）,have been prepared under ionothermal reactions using the 1-propyl-3-methylimidazolium bromide ionic liquid solvent.Single-crystal X-ray analyses reveal that 1 crystallizes in a monoclinic space group P2 1 /c,with a=8.5509（13）,b=14.804（2）,c=15.650（2）,β=97.119（2） o,V=1965.8（5） 3,Z=4,C 20 H 16 Br 2 N 4 Co,M r=531.12,D c=1.795 g/cm 3,μ=4.950 mm-1,F（000）=1044,the final R=0.0467 and wR=0.0736 for 2291 observed reflections with I 2σ（Ⅰ）.Complex 2 crystallizes in a monoclinic space group P2 1 /n,with a=10.4237（8）,b=16.8657（12）,c=12.4945（9）b,β=102.110（1） o,V=2147.7（3） 3,Z=4,C 24 H 16 Br 2 N 4 Co,M r=579.16,D c=1.791 g/cm 3,μ=4.540 mm-1,F（000）=1140,the final R=0.0431 and wR=0.1042 for 3470 observed reflections with I 2σ（Ⅰ）.The mononuclear molecules of 1 are linked by the C-H···Br hydrogen bonds and π-π interactions to form a three-dimensional supramolecular framework structure.The C-H···Br hydrogen bonds and π-π interactions link the mononuclear molecules of 2 to give a two-dimensional layer structure.

Ionic Liquids Mediated Ionothermal Process for the One-Step Synthesis of High Surface Area Alumina Supported Noble Metals

Aluminas supported noble metal nanoparticles have been synthesized by a new ionothermal process. The method used is easy to implement and allows obtaining catalysts in one step with high specific surface area. In addition, the metallic phase in the composites is highly dispersed and exhibits homogeneous size.

Co-templating Ionothermal Synthesis and Crystal Structure of a New Layered Aluminophosphate from a Protic Deep Eutectic Solvent

Protic deep eutectic mixtures are usually composed of organic amine hydrochloride salts and hydrogen bond donors in a specific molar ratio. Ionothermal synthesis of aluminophosphate as an example, herein, was reported for the first time from an urea-based protic eutectic mixture, consisting of diethylammonium chloride （DEACI） and 1,3-dimethyl urea （DMU）. As a result, a new two dimensional aluminophosphate with 4.8-network, [CH3NH3]2[（C2H5）2NH2]Al3（PO4）4, has been successfully synthesized by co-templating the DEA and methylamine in situ generated from the decomposition of DMU in the absence of HF. Compared to alkyl quaternary ammonium salts with more alkyl-group connected with N atom, this kind of organic amine salts are more likely as the struc- ture-directing agents to synthesize aluminophosphates in urea-based deep eutectic mixtures. It was also found that HF is crucial to the phase selectivity, a known compound with chain-like structure was obtained with the single methylamine as a structure-directing agent in the presence of HF. These materials were characterized by powder XRD, SEM, TG-DSC, 13C CP-MAS NMR and CHN analyses.

Ionothermal Synthesis and Structural Characterization of a Novel Open Framework Zinc Diphosphonate with Carboxylate-like Linker

A novel crystalline zinc diphosphonate, （CH3NH3）4Zn2（xbp）2·H2O, denoted as compound 1, was ionothermally synthesized from tetraethyl-p-xylylenebisphosphonate （Yexbp） and Zn（OAc）2 in a protic eutectic mixture with urea/methylamine hydrochloride. Its structure was determined by single-crystal X-ray diffraction data and had a special three-dimensional open framework with rhombic channels. Compound 1 belongs to the monoclinic system （space group C2/c）, with lattice parameters a=22.6876（19）A, b=8.7376（7）A, c=8.1673（9）A, β= 108.146（2）°, V= 1538.5（2） A^3, Z=2. Its structure is totally different from the typical organic pillared structure, only two oxygens of the phosphonate group are coordinated with zinc atoms, and the third oxygen exists in the terminal form, which is similar to the popular dicarboxylate linkers in MOFs. The organic cations [CH3NH3]^＋ of the eutectic mixture played a structure-directing role for constructing this framework and were confined in the pore channels to balance the negative charges resulting from the zinc phosphonate inorganic chains.

Ionothermal Synthesis, Structure, Thermal Properties and Magnetic Behaviors of a Novel Dinuclear Copper(Ⅱ) Coordination Compound

A novel dinuclear copper(Ⅱ)coordination compound,[CuⅡ(Hpdc)(phen)Cl][CuⅡ(pdc)(phen)]·4 H2 O(1,H2 pdc=pyridine-2,6-dicarboxylic acid,phen=1,10-phenanthroline),has been obtained by an ionothermal method using the ionic liquid 3-butyl-1-methylimidazolium bromide([Bmim]Br)as solvent,and fully characterized by elemental analyses,energy-dispersive X-ray spectroscopy(EDX),IR and single-crystal X-ray diffraction.1 belongs to the triclinic system,space group■with a=11.406(4),b=11.801(5),c=16.093(6)?,α=106.124(6)°,β=113.480(7)°,γ=93.853(7)°,Z=2,V=1942.3(13)?3,Dc=1.570 g·cm-3,F(000)=928,μ=1.235 mm-1,the final R=0.0588,wR=0.1369 and S=1.013.The compound exhibits a two-dimensional layered structure constructed by[CuⅡ(Hpdc)(phen)Cl]and[CuⅡ(pdc)(phen)]fragments via the hydrogen bonds andπ-πstacking interactions.In addition,its thermal properties and magnetic behaviors were also studied in detail.The magnetic properties revealed that there is a ferromagnetic interaction between Cu…Cu in 1.

Ionothermal Synthesis and Characterization of Two Polyoxometalate-based Supramolecules

Two novel 3D supramolecular architectures with hexamolybdate and phosphotungstate anions were syn- thesized under ionothermal conditions. The structures were named as [Cut（L1）2]2L2[Mo6O19]（1） and [Cur（L3）2]2.5· H0.5[PW12O40].H2O（2）（L1=2,2＇-bipyridine, L2=4,4＇-bipyridine, L3=2,2＇-biimidazole） and characterized via Fourier transform infrared spectroscopy（FTIR） and FT-Raman spectroscopy analyses. Single-crystal X-ray diffraction analysis revealed that the two compounds crystallized in the space group P1 and were constructed through hydrogen bonding.

Ionothermal synthesis of AlPO-34 membranes on macroporous α-Al_(2)O_(3) supports without using organic template

Continuous and compact AlPO-34 molecular sieve membranes were successfully synthesized on the outer surface of macroprous tubeα-Al_(2)O_(3)supports under secondary ionothermal growth with the proposed wetting seed layer.The recyclable ionic liquids(ILs)can both act as solvent media and the structure-directing agent(SDA)of the aiming topological structure of CHA,largely reducing the wastewater.Wetting the seed layer could accelerate the diffusion of ILs to the surface of the support and further increase the binding force between the membrane and the support.Compared with the open system,the closed system led to the achievement of the high-quality AlPO-34 membrane.The H_(2)permeance of the resulting membrane was 9.74×10^(-8)mol m^(-2)s^(-1)Pa^(-1)and the ideal selectivities of H_(2)/CO_(2),H_(2)/N_(2),H_(2)/CH_(4),H_(2)/C3H8 and H_(2)/i-C4H10 were 7.48,8.54,14.67,39.25 and 65.83,respectively,which were higher than Knudsen diffusion ratios.The obtained membrane was firstly explored for the PV dehydration of isopropyl alcohol(90 wt%)/water mixtures,exhibiting good performance with the separation factor of 147 and high water flux of 1.09 kg m^(-2)h^(-1).

Ionic liquid-assisted hydrothermal synthesis of SnS nanoparticles:Electrode materials for lithium batteries,photoluminescence and photocatalytic activities

Tin mono-sulphide（Sn S） nanoparticles（Nps） have been successfully synthesised through ionic liquid assisted hydrothermal method using hydrated tin（II） chloride as a precursor, thiourea as sulphur source precursors using 2-Methoxy ethyl methyl imidazolium methane sulfonate ionic liquid as co-solvent. The Reitveld refinement on powder X-ray diffraction（PXRD） confirmed the presence of orthorhombic Sn S structure as major phase along with traces amount of Sn S2 and Sn2 S3. Diffuse reflectance spectrum studies revealed the energy band gap around 1.38 e V. TEM images confirmed the Sn S Nps with average particle size of 40 nm and HRTEM suggest good crystallinity. The electrochemical property for lithium storage behaviour shows an initial discharge capacity of 658 m Ah/g and it retains discharge capacity of 426 m Ah/g for 16 cycles, at current density 100 m A/g. The obtained results indicate that Sn S Nps to be one of the possible promising anode materials for next generation Lithium batteries. Photoluminescence study of Sn S Nps shows a strong green emission at 530 nm. Sn S Nps were also tested for the photocatalytic adsorption of methylene blue and Rhodamine B.

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.

Atomically Precise Titanium–Oxo Nanotube with Selective Water Adsorption and Semiconductive Behaviors

We report the first example of carbon nanotube(CNT)-like assembly of the titanium(Ti)framework,Ti oxo inorganic cluster(Ti6O6)hexagonal rings into a titanium oxide(Ti–O)nanotube,prepared by ionothermal synthesis.As determined by single-crystal X-ray diffraction analysis,the Ti–O nanotube arrays,stabilized by sulfate ligands,assumed proper parallel alignment with each other and were separated by supramolecular interactions with surrounding EMIm(1-Ethyl-3-methylimidazolium)counter cations.Our stability studies indicated that the Ti–O nanotube obtained is indeed stable in air and various solvents.Also,it could maintain its structure upon heating to∼300°C.Moreover,inside the pores of the Ti–O nanotubes,a rare water molecules nanoconfinement behavior was observed at room temperature.Further,our current developed Ti–O nanotube arrays exhibited selective water adsorption over methanol and ethanol,showing potential applications for miscible solvents separations.Finally,these Ti–O nanotubes demonstrated typical semiconductive characteristics,with the electrical conductivity increasing four orders of magnitude,ranging from 3.15×10^(−10)–1.03×10^(−6)S/cm,as the temperature increased from 35 to 135°C.This work represents a milestone in constructing inorganic Ti–O nanotube arrays with atomically precise structural information for applications as visible-lightinduced photocatalysts,semiconductors,sensors,and optoelectronics.