Silicon nanocrystals functionalized with photoactive units for dual-potential electrochemiluminescence

Silicon nanocrystals (SiNCs) have attracted attention due to their unique properties that render them particularly suitable for a high variety of applications, such as electrochemiluminescence (ECL) sensors. However, the electrochemiluminescence of SiNCs has not been investigated in depth so far and the research has been focused on conventional quantum dots composed of toxic or rare materials. Here, we investigate the ECL properties of heterosupramolecular systems based on organic chromophores (diphenylanthracene, DPA) linked to the SiNC's surface. The optical properties of the nanocrystal are affected by the presence of the chromophores; their ECL behaviors are independent of each other, generating hybrid systems characterized by dual-potential electrochemiluminescence. These nanoparticles can be used as single systems with tunable dual-potential emissions; ECL signals can be varied with the type of the attached chromophore.