Layer-by-layer approach for fabricating organic/inorganic hybrid multilayers based on a polyoxyethylene-substituted perylenetetracarboxylic diimide and CdS

Abstract

An amphiphilic perylenetetracarboxylic diimide derivative (APDI) is designed and synthesized. The highly ordered APDI/CdS hybrid film was obtained successfully via a novel layer-by-layer approach by using a simple H2S-vapor annealing over each layer of APDI/Cd2+ Langmuir-Shäfer film fabricated from Langmuir monolayer of APDI molecules formed on the surface of CdCl2 aqueous solution. Examination by spectroscopic methods revealed APDI molecules in the hybrid film adopt a typical H aggregation mode whereas those in pure film adopt a slipped co-facial stacking mode in an “edge-on” conformation. The wurtzite CdS nanoparticles have been incorporated successfully into APDI matrix. The film morphology changed obviously from elongated domains of ca. 70nm in length in pure APDI film to small nanoparticles of ca. 55nm in diameter in APDI/CdS hybrid film. In particular, energy transfer from CdS to APDI has been established in the hybrid film.