Professor of Chemistry

Tel: 86-10-82615803;Fax:86-10-62569564;
Email: liumh@iccas.ac.cn

▪ Introduction

Born:   December, 1965.
1994.4-1997.7,   Special Postdoctoral Researcher, Institute of Physical and Chemical Research (RIKEN),
                           Wako-shi, Japan
1997.8-1998.1,   Researcher of Venture Business Laboratory, Tokyo University of Agriculture and Technology,
                           Tokyo, Japan
1998.2-1999.3,   Professor, Institute of Photographic Chemistry, Beijing, China.
1999.4- Present,   Institute of Chemistry, Professor of Chemistry,

Current Position:   Professor, Institute of Chemistry, CAS. Vice Director, Institute of Chemistry, CAS.

▪ Education

1982.9-186.7,   Department of Chemistry, Nanjing University.
1986.9-1988.9,   Master course, Nanjing University.
1988.9.   Selected as a student to study in Japan by the Ministry of Education of China.
1988.10-1994.3,  Doctor course, Saitama University, Japan
1994.3,   Ph. D in material science, March, 1994.
Advisor:  Kiyoshige FUKUDA

▪ Scientific Appointments

General Secretary, Amphiphiles at interface, 1999.5.24-5.27, Beijing, China.
Scientific secretary, the 10th International conference on the Organized Molecular films (LB10).10, October.6-10, 2003. Beijing, China
Vice Chairman, 12th international conferences on surface and Colloid and Science, Beijing, China, October 15-20, 2006.
Director, Division of organized molecular films, Chinese Chemical Society, (2002-
Member of Advisory board, Chinese Journal of Inorganic Chemistry (2002-
Member of Advisory board, ACTA PHYSICO-CHIMICA (2004-)
International Advisory board, Soft Matter. (2006-)

▪ Honors and Awards

Outstanding Youth Investigator Fund, Natural Science Foundation of China, (2000-2004)
CCS-BASF Youth Knowledge Innovation Prize (2005-2006)
First Prize of Science & Technology, China Association for Instrumental Analysis （2004）

▪ Research interest

1． Supramolecular chirality of the interfacial molecular assemblies: from achiral molecules to chiral molecular
       assemblies
2． Synthesis and Molecular assemblies based on bolaamphiphiles and gemini amphiphile
3． Low Molecular weight organogels

▪ Current research

1．Supramolecular chirality in the interfacial molecular assemblies

Chirality plays an important role in life and material sciences. While it is very important in the asymmetric synthesis to create chiral molecules, increasing attention has been drawn to the chiral supramolecular assemblies. Generally, the chirality of supramolecular systems can be generated through the assembly of chiral molecules or the combination of chiral and achiral molecules. On the supramolecular level, the spontaneous formation of chiral aggregate from achiral molecules is also important and currently has received much attention.

So far, in several systems such as inorganic crystals, liquid crystals, and dye aggregates in solutions have been found to form chiral crystal or aggregates under certain condition. Recently, our group has focus on the supramolecular chirality form a layers of achiral molecules through the assembly at the air/water interface and many of achiral molecules have been found to form optically active molecular assemblies.

1.1  Based on the π-π stacking and electrostatic interaction

                                  

TPPS and some of the positively charged long chain amphiphiles are found to form complex multilayer at the air/water interface. The assemblies showed macroscopic chirality, as verified from the CD spectra. It was suggested the cooperative stacking of the porphyrin rings played an important role in forming the supramolecular chirality. J. Phys. Chem. B, 2003, 107, 2565-2569.；ibid, 2003, 107, 12768 – 12773.

1.2  Interfacial coordination

                           

An amphiphilic compound 2-(heptadecyl) naphtha[2,3]imidazole (NpImC17) has been found that interfacial coordination between NpImC17 and Ag(I) ion occurred both in the monolayer and in the LB film. It is interesting to note that the Ag(I)-coordinated ultrathin film became chiral although the ligand itself is achiral.

It was suggested that the chirality of the Ag(I)-coordinated LB film was developed due to the formation of a helical coordination polymer through the interfacial coordination. J.Am.Chem.Soc., 2003, 125, 5051. Chem. Eur.J., 2005, 11, 4155.

1.3  Based on the hydrogen bond

We found that an achiral amphiphilic barbituric acid derivative could show chirality and form spirals in the LB films. It was suggested that both the H-aggregation and the directional H-bond between the BA molecules were responsible for the supramolecular chirality as well as the spiral morphology of the LB film.  J. Am. Chem. Soc., 2004, 126, 1322-23; Langmuir, 2006，22 (9): 4110-4115

Photopolymerized organized molecular films of polydiacetylene showed chirality although the monomeric amphiphilic diacetylene was achiral. Chem. Comm. 2003, 66-67.; J.Phys.Chem.B,2005, 109, 114

1.4    Annealing-induced Amplification of Supramolecular Chirality of Langmuir-Schaefer Film Exclusively from
         Achiral Porphyrin Derivatives

Achiral porphyrin derivatives were spread onto the air/water interface and then transferred onto solid substrates by Langmuir-Schaefer (LS) method. It was found that although both of the porphyrin derivatives were achiral species, the transferred LS multilayer films showed macroscopic supramolecular chirality. Interestingly, TPPOMe LS film was annealed in high vacuum and a significant amplification of the supramolecular chirality was observed. ChemPhysChem, 2006, 7, 2419.

1.5   A Supramolecular Chiroptical Switch Exclusively from an Achiral Amphiphile

Achiral TARC18 molecule could form optically active LS films through organization at the air/water interface. A chiroptical switch based on the LS films of achiral TARC18 were realized by alternately exposing the film to HCl gas and to air. Adv. Mater., 2006, 18, 177.

2.   Synthesis and Molecular assemblies based on bolaamphiphiles and gemini amphiphile

Amphiphiles played a crucial role in the formation of various organized nano/micro structures such as monolayer, LB films, vesicles, micelles and etc. Mostly investigated amphiphiles are those containing one hydrophilic headgroup and a hydrophobic tail. Recently, our group has been focused on the design and assemblies of the bolaamphiphile, which are composed of two headgroups and one or two alkyl chains, and gemini amphiphiles. Some interesting properties and nanostrutures were observed for these amphiphiles at the air/water interface.

                                                     (a)                (b)                     (c)

                     图1. (a)  typical amphiphile； (b)  bolaamphiphile； (c)  gemini amphiphile

2.1   Bolaamphiphiles

Nanostructures for the spreading film of a bolaamphiphile dicarboxylic acid through the air/water interface. Langmuir, 2003, 19, 285, Thin Solid Films, 479 (2005) 269– 276.

An L-glutamic acid terminated bolaamphiphile was spread on water surface. A simple compression of the spreading film led to the helical nanotubes. Langmuir, 2006, 22 (16): 6727-6729

2.2  Gemini amphiphiles

The formation of complex monolayers between gemini surfactants (CsH2s-???-(CmH2m+1N+(CH3)2Br-)2, abbreviated as C12-Cs-C12, s ) 3, 4, 6, 8, 10, 12) and DNA at the air-water interface was systematically investigated. The polyion-complex monolayers formed in situ through the electrostatic attraction between the ammonium groups of gemini surfactants and the phosphate groups of DNA. The effect of surfactant spacer length on the surface properties was investigated. A turning point of the surface properties (extrapolated molecular area and collapse pressure) of the gemini surfactant/DNA complex monolayers appears when the surfactant spacer is above a certain length (s ) 6)., Langmuir, 2002, 18, 6222-6227

.

The ultrathin hybrid multilayer films were fabricated through the in situ complex formation between an oval decatungstoeuropate (EuW10) and a series of gemini-type amphiphiles with various lengths of the flexible hydrophobic spacers at the air/water interface. The photoluminescence properties of the hybrid films were investgated. A size matching between EuW10 and the gemini amphiphile with a hexamethylene spacer was observed, which showed the lowest ratio of the emission intensity of 5D0f7F2 to that of 5D0f7F1. Langmuir,
2005, 21, 11128-11135.

The adsorption and aggregation of TPPS and a selenacarbocyanine dye onto Langmuir monolayers of a series of gemini amphiphiles with different methylene spacers were investigated. The dyes formed complex films with the amphiphiles and the transferred films showed different morphologies. The spacer could affect the aggregation as well as the supramolecular chirality of the complex films. J.Phys.Chem. B 2004，108, 7180-7185.; ibid, 2006, 110, 10455-10460.

3.   Low Molecular weight organogels

Low molecular mass organic gelators (LMOGs) are an important class of compounds that are capable of gelling organic or aqueous fluids. These gels, usually called organogels, are thermoreversible. The gelator molecules, having lower molecular weight and defined structures, can self-assemble in solvents to form various supramolecular architectures such as nanofibers, nanorods, nanotubes, helices, ribbons. Various applications in materials science and biology make this class of small organic molecules attractive. We have designed a bolaamphiphile containing L-glutamic acids in the two ends. When this compounds was dissolved in the mixed solvent of EtOH and water at a higher temperature, and cooled to room temperature. It formed a helical nanotube. Such nanotube were further used as a template to synthesis the multilayer-wall silver nanotube in a controlled manner. Chem. Commun.2005, 462-464. Langmuir, 2006, 22, 775-779.

▪ Selected publications

Supramolecular Chirality in the Interfacial assembled films

1． Peizhi Guo, Li Zhang, Minghua Liu, "A supramolecular chiroptical switch exclusively from an achiral
       amphiphile", Adv.Mater., 2006, 18 (2), 177. [View]
2． Xin Huang, Minghua Liu, "Regulation of supramolecular chirality and morphology of the LB film of achiral
       barbituric acid by amphiphilic matrix molecules", Langmuir, 2006, 22 (9): 4110-4115. [View]
3． Xin Huang, Siguang Jiang, Minghua Liu，"Metal Ion Modulated Organization and Function of the
       Langmuir-Blodgett Films of Amphiphilic Diacetylene: Photopolymerization, Thermochromism, and
       Supramolecular Chirality", J. Phys. Chem. B，2005, 109, 114-119. [View]
4． Zongxia Guo, Jing Yuan, Yong Cui, Fei Chang, Wenhua Sun, Minghua Liu, "Supramolecular Assemblies
       of a series of 2-Arylbenzimidazoles at the Air/Water Interface: In situ Coordination, Surface Architecture and
       Supramolecular Chirality", Chem.Eur. J. 2005, 11, 4155-4162. [View]
5． Peizhi Guo, Rupei Tang, Caixia Cheng, Fu Xi, Minghua Liu,I "nterfacial Organization-Induced Supramolecular
      Chirality of the Langmuir-Schaefer Films of a Series of PPV Derivatives",
      Macromolecules,  2005, 38, 4874-4879. [View]
6． Peizhi Guo, Minghua Liu, "Fabrication of Chiral Langmuir-Schaefer Films of Achiral Amphiphilic Schiff Base
       Derivatives through an Interfacial Organization", Langmuir, 2005, 21, 3410-3412. [View]
7． Xin Huang, Chao Li, Siguang Jiang, Xuesong Wang, Baowen Zhang, Minghua Liu, "Self-assembled Spiral
       nanoarchitecture and supramolecular chirality in Langmuir-Blodgett Films of an Achiral Amphliphilic Barbituric
       Acid", J. Am. Chem. Soc., 2004, 126, 1322-1323. [View]
8． Xiaodong Zhai, Li Zhang, Minghua Liu, "Supramolecular assemblies between a new series of gemini-type
       amphiphiles and TPPS at the air/water interface: Aggregation, chirality, and spacer effect", J. Phys. Chem.
       B, 2004, 108, 7180-7185. [View]
9． Li.Zhang, Qing.Lv, Minghua.Liu, "Fabrication of chiral Langmuir-Schaefer films from achiral TPPS and
      amphiphiles through the adsorption at the airwater interface",
      J. Phys. Chem. B, 2003, 107, 2565-2569. [View]
10.  Li Zhang, Jing Yuan, Minghua Liu, "Supramolecular Chirality of Achiral TPPS Complexed with Chiral
       Molecular Films", J. Phys. Chem. B, 2003，107, 12768 – 12773. [View]
11.  Jing Yuan, Minghua Liu, "Chiral molecular assemblies from a novel achiral amphiphilic 2-
       (heptadecyl)naphtha[2,3]imidazole through interfacial coordination",
       J. Am. Chem. Soc., 2003, 125, 5051-5056. [View]
12.   Xin.Huang, Minghua.Liu, "Chirality of photopolymerized organized supramolecular polydiacetylene films",
        Chem.Commun., 2003, 66-67. [View]

Design and Assembly of bolaamphiphile and gemini amphiphile

Assembly of DNA

Low Molecular weight organogels