Pore-confined synthesis of mesoporous nanocrystalline La-Ce phosphate films for sensing applications

• Published in: Journal of materials chemistry 2012-01, Vol.22 (38), p.2498-253
• Main Authors: Marongiu, Daniela, Carboni, Davide, Malfatti, Luca, Innocenzi, Plinio
• Format: Article
• Language: English
• ISSN: 0959-9428; 1364-5501
• DOI: 10.1039/c2jm34566h

A new method for the preparation of fluorescent mesoporous La-Ce phosphate films by spin coating is reported here. The structure is obtained by a pore-confined synthesis involving an in situ growth of La 0.5 Ce 0.5 PO 4 nanoparticles inside the pores of a mesoporous silica thin film and the subsequent partial sintering. The removal of the sacrificial mesoporous silica matrix is achieved by chemical etching, which leaves on the substrate a La 0.5 Ce 0.5 PO 4 mesoporous film exhibiting good adhesion properties and high fluorescence intensity that can be quenched by a water solution containing organo-phosphate bearing nitrophenyl groups. The sensing capabilities of these materials have been tested for the detection of pesticides in water. Fluorescent mesoporous La-Ce phosphate films have been synthesized by a pore-confined strategy involving an in situ growth of La 0.5 Ce 0.5 PO 4 nanoparticles inside the pores of a sacrificial mesoporous silica film. The films exhibit high fluorescence intensity that can be exploited to detect pesticides or other organo-phosphate compounds bearing nitrophenyl groups in water.