Copolymers nanocrystalline

Ravirajan P., Haque S. A., Durrant J. R., Poplavskyy D., Bradley D. D. C. and Nelson J. (2004), Hybrid nanocrystalline TiOi solar cells with a fluorene-thiophene copolymer as a sensitizer and hole conductor , J. Appl. Phys. 95, 1473-1480. 

Surfactant templating chemistry can be extended to many nonsilicate compositions after modifications to the synthesis route. These materials are less structurally stable than the mesoporous silicates, which is attributed to the thinness of the amorphous pore walls ( 1 to 2 nm). Stucky and coworkers [85,86] showed that this problem could be mitigated by preparing the materials with thicker walls. To prepare mesoporous WO3, they dissolved a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer and WCle salt in ethanol, and dried the resulting solution in open air. The tungsten salt reacted with moisture to undergo hydrolysis and condensation reactions. These chemical reactions caused the eventual formation of amorphous WO3 around triblock copolymer micelle-like domains, and after calcination at 400 C, a mesoporous WO3 with thick, nanocrystalline walls ( 5 nm) and surface area of 125 m /g was formed. 

Zhang, J., Gao, Y, Alvarez-Puebla, R. A., Buriak, J. M., and Fenniri, H. (2006) Synthesis and SERS properties of nanocrystalline gold octahedra generated from thermal decomposition of HAuCU in block copolymers, Adv. Mater., 18(24), 3233-3237. 

In comparison with the materials synthesized in the presence of surfactants, the surface area of the hierarchically porous zirconium oxides obtained via the self-formation phenomenon is relatively lower. Furthermore, the synthesis temperature can affect the crystallinity of the final product [124,139]. Upon increase of the hydrothermal treatment temperature to 130 °C (generally reported to be 60-80 °C), thermally stable meso-macroporous zirconias with a nanocrystalline framework were prepared by using a mixture of amphiphilic block copolymer P123 and poly(ethylene oxide) surfactant Brij 56. 

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