Luminescence modulation with semiconductor quantum dots and photochromic ligands

Abstract

We have attached a photochromic spiropyran to the surface of CdSe-ZnS core-shell quantum dots, relying on a dithiolane anchoring group. In the resulting assembly, the reversible interconversion of the photochromic component activates and suppresses an energy transfer pathway from the excited quantum dots to the coloured state of the ligand. As a result, the luminescence intensity decreases by 45% with the photoinduced colouration of the spiropyran and returns to the original value after the thermal reisomerization of the ligand. © CSIRO 2006.