Seminar: Soft Optical and Electronic Materials: Development of Conjugated Polymers and Supermolecular Machines

This seminar will be of interest to anyone working in photovoltaics, organic electronics, organic chemistry and supermolecular chemistry.

Friday 12th July, 1pm-2pm, Seminar Room 211, School of Electronic engineering, Dean street

Prof Masaki Horie, Department of Chemical Engineering, National Tsing-Hua University, Taiwan

Donor-acceptor alternating conjugated copolymers are of great interest as these materials show low optical band gap properties leading to the high performances as active materials in organic photovoltaics (OPVs) as well as organic field-effect transistors (OFETs). Despite the high performances of the copolymers, the synthetic scale-up of the material has not been well investigated. This is due to some problematic processes in Suzuki and Stille coupling reactions; Suzuki coupling requires unstable boronic acids; Stille coupling requires toxic tin compounds. In this presentation, we report the synthesis of materials such as PCPDTBT via palladium catalysed direct arylation between cyclopentadithiophene (CPDT) and 4,7-dibromobenzothiadiazole (Br-BT-Br). The polymerisation conditions were optimised, which to afford optimal polymer properties. The use of these polymers in bulk-hetero junction (BHJ) type OPV devices is discussed. 

The second part of this talk is focused on Organometallic supramolecular systems, which exhibit specific optical, electrochemical, and catalytic properties and have been of great interest in supramolecular chemistry. In this context, organometallic moiety in rotaxanes and pseudorotaxanes which are composed of a ring molecule and an axle molecule has been used as redox, catalytic, or photo-harvesting centers. Recently, we discovered a first-order solid-to-solid thermal transition of the pseudorotaxane crystal, which corresponds to partial structural changes of axle molecules in the crystal state.  In the presentation, we report a precise structural characterization of the phase transition of the pseudorotaxane crystal using X-ray crystallography. The change in crystal shape and optical anisotropy is also mentioned.

References

1) S.-W. Chang, H. Waters, J. Kettle, Z.-R. Kuo, C.-H. Li, C.-Y. Yu, M. Horie Macromol. Rapid Commun., 2012, 33, 1927.
2) S.-W. Chang, H. Waters, J. Kettle, M. Horie Org. Electron. 2012, 13, 2967.
3) M. Horie, T. Sassa, D. Hashizume, Y. Suzaki, K. Osakada, T. Wada, Angew. Chem. Int. Ed. 2007, 46, 4983.
4) M. Horie, Y. Suzaki, D. Hashizume, T. Abe, T. Wu, T. Sassa, T. Hosokai, K. Osakada, J. Am. Chem. Soc. 2012, 134, 17932.
5) H. Waters, J. Kettle, S.-W. Changb, C. Su, W. Wu, U. Jeng, Y. Tsai, M. Horie J. Mater. Chem. A, 2013, 1, 7370-7378

Biography

Masaki Horie obtained a PhD at Tokyo Institute of Technology working on organometallic supramolecules under the supervision of Prof. Kotaro Osakada. Masaki then moved to RIKEN (The Institute of Physical and Chemical Research) as a special postdoctoral researcher working on crystal optics of supramolecules. In May 2007, he joined The University of Manchester working with Prof. Michael Turner and Prof. Brian Saunders at the Organic Materials Innovation Centre (OMIC). Whilst there he had worked on the hybrid solar cell project using conjugated polymers and inorganic quantum dots. In February 2010, he joined Department of Chemical Engineering at National Hsing Hua University in Taiwan. His research interests are synthesis of conjugated polymers and supermolecular rotaxanes for use in organic opto-electronic devices.

Publication date: 25 June 2013