Abstract

This work describes the construction of layered Langmuir-Blodgett (LB) films of a calixarene and the use of these as matrices for the synthesis of a range of metal sulfide nanoparticles. CuS, CdS, HgS, and PbS nano-clusters were formed within LB films of an octa-tertbutyl-calix(8)arene substituted with carboxylic acid groups deposited on different substrates (glass, quartz, and silicon) from either: (i) aqueous sub-phases containing 0.5 mM of the respective metal chloride salt (e.g. CuCl2, CdCl2, HgCl2, PbCl2), or (ii) by soaking the LB films in 10 mM solutions of the above salts for 1 h. The formation of metal-sulfide (MeS) nanoparticles was then achieved by exposing samples to H2S gas for 10–12 h.Deposition from salt containing subphases was more reliable and resulted in stoichiometric metal sulfides (CdS, HgS, PbS) being formed within LB films of the calix(8)arene carboxylic acid whereas Cu tended to form polysulfides. UV–vis absorption spectroscopy showed the presence of multiple absorption bands corresponding to electron transitions between energy levels in nanoclusters formed as result of quantum confinement of electrons and holes. The MeS clusters obtained by this process are amongst the smallest reported for LB films, being of the range 0.6–1.2 nm.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call