Ag/Ag sub(2)S heterodimers: tailoring the metal-semiconductor interface in a single nanoparticle

Heterodimers are conjoined particles of two inorganic materials, and they are generally synthesised in multiple steps. But, the multi-step syntheses are less effective because of the low yield, long reaction time, labour intensive process and complexity in the synthesis and thus not ideal for scale up. Herein, we have demonstrated single-step, one-pot syntheses for two different types of Ag/Ag sub(2)S heterodimers. Two types of heterodimers were obtained while varying stoichiometry in the reaction of AgNO sub(3) with sulphur in the presence of hexamethyldisilazane (HMDS) at 140 degree C. To the best of our knowledge, this was the first demonstration of single-step process to synthesise Ag/Ag sub(2)S heterodimers. Heterodimers had dumbbell shape with both metal and semiconductor domains in single particle which were constructed by spherical Ag and Ag sub(2)S nanoparticles. Ag (2 0 0) and Ag sub(2)S (0 2 2) planes associated to form heterodimers. The presence of metal-semiconductor interfaces was confirmed by HRTEM and UV analysis. Thus, we have demonstrated the HMDS-assisted synthesis as a promising method for direct synthesis of Ag/Ag sub(2)S heterodimers. [Figure not available: see fulltext.]