Enhanced photo-luminescence of CdX (X= S, Se, Te) Q-dots embedded in ordered mesoporous silica thin films

DIEGO ONNA; MARTINEZ RICCI, MARIA LUZ; SARA ALDABE BILMES

Kyoto

Congreso; Sol Gel 2015; 2015

Photo-luminescence (PL) of Q-dots can be tuned by the particle diameter, crystallinity and density of surface states (SS). In particular, SS provide a non-radiative recombination and/or a radiative decay at low energies, far from the excitonic emission. In this work we explore the formation and the PL of Q-dots grown in ordered mesoporous oxides (OMPO) where pores act as nanoreactors leading to confined quasi-spherical nanoparticles (NPs) whose size is limited by pore diameter fixed by the molecular template.OMPO films were prepared following the conventional protocols[1], using different amphiphillic templates to tune pore radios (3-9nm). Q-dots were grown by successive impregnations in Cd2+ and X precursor solutions. Samples were characterized by UV-Vis, SEM, HRTEM, and Environmental Ellipsometric Porosimetry (EEP). Steady state PL was measured at different excitation wavelengths in order to get the maximum intensity for each system.