Multifunctional semiconductor nanoheterostructures via site-selective silica encapsulation.

Site-specific silica encapsulation of the CdSe core region of CdSe/CdS tetrapods is employed to allow for the fluorescence from the CdSe core to be preserved during the growth of secondary functional materials, which is exploited to achieve Ag2S-tipped SiO2-CdSe/CdS tetrapods with dual emission at visible and IR wavelengths and Au/FexOy-tipped SiO2-CdSe/CdS tetrapods which exhibits both fluorescence and a strong magnetic response.