Synthesis of solid solutions of Cd1-xZnxS nanocrystals in the channels of mesostructured silica films

In this contribution, we introduce the use of metal ion (Cd(II) and Zn(II)) modified mesostructured silica as a reaction medium, to produce a solid solution of Cd1-xZnxS nanocrystals as a thin film. With this approach, a true liquid crystalline templating (TLCT) and liquid crystalline mesophase of transition metal salt : oligo( ethylene oxide) non-ionic surfactant ((( 1 - x)[Cd(H2O)(4)](NO3)(2) + x[Zn(H2O)(6)](NO3)(2)) : CH3(CH2)(11)(OCH2CH2)(10)OH, (MLC)), systems were collectively used to synthesise mesostructured silica films. The film samples were reacted at room temperature (RT) in an H2S atmosphere to produce zinc blend Cd1-xZnxS nanocrystals in the channels of mesostructured silica. The initial Zn( II) and Cd( II) ion concentrations in the reaction media determine the final composition and band gap of the Cd1-xZnxS nanocrystals. The growth process of the Cd1-xZnxS nanocrystals in the pores is influenced by the silica walls. If the walls are rigid ( well polymerized, obtained by aging the samples before H2S treatment), then the Cd1-xZnxS nanoparticles are smaller in size and more uniform in size distribution.