Highly Efficient Precursors for Direct Synthesis of Tailored CdS Nanocrystals in Organic Polymers

• Published in: Journal of physical chemistry. C Vol. 114; no. 41; pp. 17311 - 17317
• Main Authors: Resta, Vincenzo, Laera, Anna M, Piscopiello, Emanuela, Schioppa, Monica, Tapfer, Leander
• Format: Journal Article
• Language: English
• Published: American Chemical Society 21.10.2010
• Subjects: C: Nanops and Nanostructures
• ISSN: 1932-7447; 1932-7455
• DOI: 10.1021/jp104097w

An innovative unimolecular precursor structure based on cadmium-bis(benzylthiolates), Cd(SBz)2, has been devised for the preparation of polymer/CdS nanocomposite materials through a simple and inexpensive synthetic route. Cd(SBz)2 and [Cd(SBz)2]2·MI, MI being methyl imidazole, dispersed in a polymer matrix have been later thermolyzed in very mild conditions in the range of temperatures, T A, 175 °C ≤ T A ≤ 240 °C. Optical absorbance, photoluminescence spectroscopy, and X-ray diffraction show that, for both precursors, CdS nanocrystal (NC) nucleation and growth start well below the literature threshold values and that in the analyzed temperature range the NC’s size is finely tuned in quantum confinement regime conditions. Methyl imidazole added precursor shows highly efficient reactivity at lower temperatures, while the differences become smaller for higher values. Transmission electron microscopy ensures that in the entire range of temperatures, the synthesis of highly dense and homogeneous distributed CdS NCs over the whole extent of the matrix has been achieved with [Cd(SBz)2]2·MI precursor. The results show that benzylthiolates are really promising molecules as precursors for optoelectronic and/or photovoltaic nanocomposite based devices.