本发明公开了一种光响应的离子液体及其制备方法。离子液体的结构具有如下通式，该离子液体含有光响应的偶氮苯基团，在溶液和纯液态情况下均可保持良好的光 致变色(异构)性能，在光的作用下能实现离子液体的物理化学性质例如紫外可见吸收光谱、荧光发射光谱和电导率的可逆变化，可以作为一种优良的信息存储材 料、光开关分子器件、导电的光致变色(异构)材料和光敏感材料。

邓友全,张世国,张庆华. 一种光响应的离子液体及其制备方法. 200710307474.0. 2010.

Because of its sensitivity to chemical and electrostatic characteristics, nitrile group as an infrared (IR) probe to monitor the local structure, folding kinetics, and electrostatic environment of protein, or solvation of molecular solvents, has attracted increasing attention. Herein, by choosing benzonitrile and imidazolium ionic liquids (ILs) as the IR probe and model ILs, respectively, we report that the nitrile stretching vibration (νCN) could be utilized as a simple and substantial IR probe to monitor the local environment of ILs such as hydrogen bonding (H-bonding) as well as intrinsic electric field. In 1-alkyl-3-methylimidazolium-based non-hydroxyl ILs, the νCN is in a “free” state, and is less affected by the alkyl chain, while it significantly decreases with the effective anion charge. In 1-(2-hydroxyethyl)-3-methylimidazolium-based hydroxyl ILs, however, a distinct anion-dependent νCN forming H-bonding with the hydroxyl is also observed besides the “free” νCN band. The “free” component of νCN can be further employed to determine the intrinsic electric field in both non-hydroxyl (directly) and hydroxyl (indirectly by subtracting H-bonding contribution) ILs by using vibrational Stark effect. Moreover, the result suggests that benzonitrile is preferentially located in the charge domain in ILs and it could be a more suitable probe to report the ionic network rather than the nonpolar domain in ILs.

★★★☆☆ Zhang SG,Zhang Y,Ma XY,et al. Benzonitrile As A Probe Of Local Environment In Ionic Liquids[J]. J. Phys. Chem. B,2013,117:2764-2772.

Electric fields of ionic liquids (ILs) were investigated by vibrational Stark effect spectroscopy using ethyl thiocyanate as a probe molecule. It was found that the stretching vibration of C≡N in nonhydroxyl ILs originates exclusively from the intrinsic electric fields, which are on average 3.0 MV cm^-1 higher than those of molecular solvents. In contrast, in the case of hydroxyl functional ILs, hydrogen bonding as well as the electric field contribute to the IR shift of C≡N.

★★★☆☆ Zhang SG,Zhang Y,Deng YQ. Investigation Of The Intrinsic Electric Field Of Nonhydroxyl And Hydroxyl Ionic Liquids By Vibrational Stark Effect Spectroscopy[J]. Rsc Advances,2013,3:11480-11484.

★★★★☆ Zhang SG,Shi R,Ma XY,et al. Intrinsic Electric Fields In Ionic Liquids Determined By Vibrational Stark Effect Spectroscopy And Molecular Dynamics Simulation[J]. Chem. Eur. J.,2012,18:11904-11908.

Ionic liquids (ILs)-stabilized iron oxide (Fe2O3) nanoparticles were synthesized by the ultrasonic decomposition of iron carbonyl precursors in [EMIm][BF4] without any stabilizing or capping agents. The Fe2O3 nanoparticles were isolated and characterized by X-ray powder diffraction, transmission electron microscopy and susceptibility measurements. The physicochemical properties of ILs containing magnetic Fe2O3 nanoparticles (denoted as Fe2O3@[EMIm][BF4]), including surface properties, density, viscosity and stability, were investigated in detail and compared with that of [EMIm][BF4]. The Fe2O3@[EMIm][BF4] can be directly used as magnetic ionic liquid marble by coating with hydrophobic and unreactive polytetrafluoroethylene (PTFE), for which the effective surface tension was determined by the puddle height method. The resulting magnetic ionic liquid marble can be transported under external magnetic actuation, without detachment of magnetic particles from the marble surface that is usually observed in water marble.

★★★☆☆ Zhang SG,Zhang Y,Wang Y,et al. Sonochemical Formation Of Iron Oxide Nanoparticles In Ionic Liquids For Magnetic Liquid Marble[J]. Phys. Chem. Chem. Phys.,2012,14:5132-5138.

The polarity of ionic liquids (ILs), usually denoted as ET(30) by the solvatochromic probe Reichardt’s dye, is one of the most fundamental properties that remarkably affect the solvation and chemical reaction in ILs. It was generally accepted that the ET(30) of ILs was dominated by the nature of the cation. However, in this work, it was found that the common ammonium-based ILs showed strongly anion-dependent ET(30). For example, the ET(30) value for [N1124][DCA] and [N1124][NTf2] is 49.0 and 59.0 kcal mol 1, respectively, while the corresponding imidazolium ILs bearing the same anions possess nearly identical ET(30), the ET(30) value for [BMIm][DCA] and [BMIm][NTf2] is 51.4 and 51.6 kcal mol 1, respectively. Moreover, introduction of an ether group was found to increase the ET(30) of imidazolium ILs while having no obvious effect on that of ammonium-based ILs. The Kamlet–Taft parameters and density functional theory (DFT) calculations indicated that the distinct result is related to different stabilization of the ground state of Reichardt’s dye 30. In imidazolium ILs, the main interactions between ILs and zwitterionic dye involve both coulombic interaction (between the cation and the phenolate oxygen atom) and H-bonding interaction (between the acidic hydrogen on imidazolium ring and the phenolate oxygen atom). However, with the ammonium ILs lack of active hydrogen, the dye is only stabilized by the coulombic interaction between the cation and the phenolate oxygen atom. Interestingly, in both imidazolium and ammonium-based ILs, the spiropyran–merocyanine equilibrium exhibit obvious anion-dependent photochromism, solvatochromism, and thermal relaxation.

★★★☆☆ Zhang SG,Chen ZJ,Qi XJ,et al. Distinct Influence Of The Anion And Ether Group On The Polarity Of Ammonium And Imidazolium Ionic Liquids[J]. New J. Chem.,2012,36:1043-1050.

★★★☆☆ Zhang SG,Liu SM,Zhang Y,et al. Photoinduced Isothermal Phase Transition Of Ionic Liquid Crystals[J]. Chemistry – An Asian Journal,2012,7(9):2004-2007.

Gas-phase structure, hydrogen bonding, and cation–anion interactions of a series of 1-(2-hydroxyethyl)-3- methylimidazolium ([HOEMIm]+)-based ionic liquids (hereafter called hydroxyl ILs) with different anions (X=[NTf2]–, [PF6]–, [ClO4]–, [BF4]–, [DCA]–, [NO3]–, [AC]– and [Cl]–), as well as 1-ethyl-3-methylimizolium ([EMIm]+)-based ionic liquids (hereafter called nonhydroxyl ILs), were investigated by density functional theory calculations and experiments. Electrostatic potential surfaces and optimized structures of isolated ions, and ion pairs of all ILs have been obtained through calculations at the Becke, three-parameter, Lee–Yang–Parr/6-31+G(d,p) level and their hydrogen bonding behavior was further studied by the polarity and Kamlet–Taft Parameters, and 1H-NMR analysis. In [EMIm]+-based nonhydroxyl ILs, hydrogen bonding preferred to be formed between anions and C2–H on the imidazolium ring, while in [HOEMIm]+-based hydroxyl ILs, it was replaced by a much stronger one that preferably formed between anions and OH. The O–H___X hydrogen bonding is much more anion-dependent than the C2–H___X, and it is weakened when the anion is changed from [AC]– to [NTf2]–. The different interaction between [HOEMIm]+ and variable anion involving O–H___X hydrogen bonding resulted in significant effect on their bulk phase properties such as 1H-NMR shift, polarity and hydrogen-bond donor ability (acidity, a).

Keywords: calculation; cation–anion interaction; hydrogen bonding; hydroxyl; ionic liquids; polarity

★★★☆☆  Zhang SG,Qi XJ,Ma XY,et al. Investigation Of Cation–anion Interaction In 1-(2-hydroxyethyl)-3-methylimidazolium-based Ion Pairs By Density Functional Theory Calculations And Experiments[J]. J. Phys. Org. Chem.,2011,25(3):248-257.

A new class of azobenzene-based photoresponsive ionic liquids was prepared and showed reversible modulation of ionic conductivity in specific solvents under alternative UV/visible light irradiation.

★★★★☆ Zhang SG,Liu SM,Zhang QH,et al. Solvent-dependent Photoresponsive Conductivity Of Azobenzene-appended Ionic Liquids[J]. Chem. Commun.,2011,47:6641-6643.

★★★☆☆ Zhang SG,Hu XD,Qu C,et al. Enhanced And Reversible Contact Angle Modulation Of Ionic Liquids In Oil And Under Ac Electric Field[J]. Chemphyschem,2010,11:2327-2331.