NUS: Department of Chemistry

Associate Professor CHIN WEE SHONG

B.Sc.(Hons), 1987, National University of Singapore;
Ph.D., 1993, National University of Singapore

Contact Information

Department of Chemistry, NUS
3 Science Drive 3
Singapore 117543

Office: S7-04-15
Tel: (65)-6516-8031
Fax: (65)-6779-1691
Email: chmcws@nus.edu.sg

Nanomaterials and Spectroscopy

One of our research goals is to explore and understand the fundamental properties of materials with physical dimension in between individual molecules and the bulk. These nanometer scaled materials have physical characteristics that are derived from the bulk materials, but their electronic and optical properties can be manipulated by controlling the size, the surface and the shape of the particles.

Currently, our research focuses on the synthesis and characterization of several types of nanomaterials including: (i) semiconducting sulfide and oxide nanocrystals (ii) core/shell and doped functional nanomaterials, (iii) hybridized nanoparticles/polymer composites, (iv) nanomagnets, and (v) surface-derivatized metallic nanoparticles. We aim to optimize the properties of these nanomaterials via chemical preparation and improve their desired functions with various characteristics. Most of our projects involve multidisciplinary collaborative efforts.

By carefully controlling the preparation parameters, we have successfully prepared Ag₂S nanocrsytals in cube, faceted or rods shapes.


TEM image of CdS nanoparticles network within polymer matrix

Representative Publications

Nanomaterials:

Water-soluble CdS quantum dots prepared from a refluxing single precursor in aqueous solution, Z.H. Zhang, W. S. Chin, J.J. Vittal, J. Phys. Chem. B, 108, 18569, 2004.

Preparation of Ag₂S nanocrystals of Predictable Shape and Size, Lim W P, Zhang Z, Low H Y and Chin W S, Angew. Chem. Int. Edn, 43, 5685, 2004.

IR-luminescent PbS-polystyrene Nanocomposites Prepared from Random Ionomers in Solution, Lim W P, Low H Y and Chin W S, J. Phys. Chem. B, 108, 13093, 2004.

Three-dimensional self-assembled monolayer (3D SAM) of n-alkanethiols on copper nanoclusters, T. P. Ang, T. S. A. Wee, W. S. Chin, J. Phys. Chem. B, 108, 11001, 2004.

Excitonic Nonlinear Absorption in CdS Nanocrystals Studied Using Z-scan technique, J. He, W. Ji, G.H. Ma, S.H. Tang, H.I. Elim, W.S. Sun, Z.H. Zhang, W. S. Chin, J. Appl. Phys. 95, 6381, 2004.

Synthesis and characterization of Eu:Y2O3 nanoparticles, H Huang, GQ Xu, W S Chin, L M Gan and C H Chew, Nanotechnology, 13, 318, 2002.

Synthesis, Characterization and Nonlinear Optical Properties of Hybridized CdS-polystyrene Nanocomposites, Du H, Xu G Q, Chin W S, Huang L, Ji W, Chem. Mater. 14, 4473, 2002.

Spectroscopy:

Electronic structure of very strong neutral bases, I. Novak, X Wei, W S Chin, J. Phys. Chem. A, 105, 1783, 2001.
Dry thienylation of the silicon (111)-(7 x 7) surface, Cao Y, Yong KS, Wang ZQ, Chin WS, Lai YH, Deng JF, Xu GQ, J. Am. Chem. Soc. 122: (8) 1812-1813, 2000
A comparative ab initio and DFT study of neutral aniline oligomers, S. L. Lim, K. L. Tan, E. T. Kang, and W. S. Chin, J. Chem Phys. 112: (23) 10648-10658, 2000.
The alternative thermal decomposition mode of 2-oxetanone and 2-azetidinone: a DFT and PES study, C. C. Lim, Z. P. Xu, H. H. Huang, C. Y. Mok and W. S. Chin, Chem Phys Lett., 325: (4), 433-439, 2000.