Visible Colloidal Nanocrystal Silicon Light-Emitting Diode

We herein demonstrate visible electroluminescence from colloidal silicon in the form of a hybrid silicon quantum dot−organic light emitting diode. The silicon quantum dot emission arises from quantum confinement, and thus nanocrystal size tunable visible electroluminescence from our devices is highlighted. An external quantum efficiency of 0.7% was obtained at a drive voltage where device electroluminescence is dominated by silicon quantum dot emission. The characteristics of our devices depend strongly on the organic transport layers employed as well as on the choice of solvent from which the Si quantum dots are cast.