Synthesis of hybrid organic–inorganic nanocomposite materials based on CdS nanocrystals for energy conversion applications

• Published in: Journal of nanoparticle research : an interdisciplinary forum for nanoscale science and technology Vol. 13; no. 11; pp. 5705 - 5717
• Main Authors: Laera, A. M., Resta, V., Ferrara, M. C., Schioppa, M., Piscopiello, E., Tapfer, L.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01-11-2011; Springer Nature B.V
• Subjects: Annealing; Cadmium; Cadmium sulfides; Characterization and Evaluation of Materials; Chemistry and Materials Science; Energy conversion; Inorganic Chemistry; Lasers; Materials Science; Nanocomposites; Nanocrystals; Nanomaterials; Nanoparticles; Nanostructure; Nanotechnology; Optical Devices; Optics; Photonics; Photovoltaics; Physical Chemistry; Polymers; Solar cells; Solar energy; Special Issue: Nanostructured Materials 2010; Titanium dioxide; Conjugated polymers; Nanocomposites; Semiconductor nanocrystals; In situ synthesis; Hybrid organic–inorganic; Unimolecular; Sustainable development; Photovoltaics
• ISSN: 1388-0764; 1572-896X
• DOI: 10.1007/s11051-011-0304-4

Efficient solar energy conversion is strongly related to the development of new materials with enhanced functional properties. In this context, a wide variety of inorganic, organic, or hybrid nanostructured materials have been investigated. In particular, in hybrid organic–inorganic nanocomposites are combined the convenient properties of organic polymers, such as easy manipulation and mechanical flexibility, and the unique size-dependent properties of nanocrystals (NCs). However, applications of hybrid nanocomposites in photovoltaic devices require a homogeneous and highly dense dispersion of NCs in polymer in order to guarantee not only an efficient charge separation, but also an efficient transport of the carriers to the electrodes without recombination. In previous works, we demonstrated that cadmium thiolate complexes are suitable precursors for the in situ synthesis of nanocrystalline CdS. Here, we show that the soluble [Cd(SBz)
2
]
2
·(1-methyl imidazole) complex can be efficiently annealed in a conjugated polymer obtaining a nanocomposite with a regular and compact network of NCs. The proposed synthetic strategies require annealing temperatures well below 200 °C and short time for the thermal treatment, i.e., less than 30 min. We also show that the same complex can be used to synthesize CdS NCs in mesoporous TiO
2
. The adsorption of cadmium thiolate molecule in TiO
2
matrix can be obtained by using chemical bath deposition technique and subsequent thermal annealing. The use of NCs, quantum dots, as sensitizers of TiO
2
matrices represents a very promising alternative to common dye-sensitized solar cells and an interesting solution for heterogeneous photocatalysis.