Aqueous synthesis of CdS and CdSe/CdS tetrapods for photocatalytic hydrogen generation

Abstract

Straightforward, easily upscalable synthesis of monodisperse CdS and CdSe/CdS nanocrystals at room temperature in water/ethylendiamine mixtures is demonstrated, resulting in the formation of high-quality tetrapod-shaped nanoparticles in aqueous environment. It offers advantages for the subsequent direct use of aqueous-based colloidal nanocrystals for photocatalytic hydrogen generation from water, as it avoids any additional phase transfer necessary for any commonly employed nanoparticles synthesized in organic medium. Being decorated with platinum as a co-catalyst, CdSe/CdS tetrapods achieve hydrogen evolution rates of up to 25 mmol/g per hour, which favorably compares to previously reported studies on CdS nanorods.