Synthesis of Metal−Semiconductor Core−Shell Nanoparticles Using Electrochemical Surface-Limited Reactions

We report the synthesis of Au/CuI and Au/CdS core−shell nanoparticle (NP) thin films using codeposition and electrochemical atomic layer deposition (EC-ALD). Au nanoparticle films were prepared on glassy carbon supports by depositing alternating layers of poly(diallyl dimethylammonium)-stabilized Au nanoparticles and CoP2W17O61 8− polyoxometallate interlayers. From there, CuI was deposited onto the surface of Au nanoparticles using electrochemical atomic layer deposition, while CdS films were grown by an atom-by-atom codeposition method. The semiconductor−Au core−shell nanoparticles were characterized by electrochemistry, photoluminescence spectroscopy, and Raman spectroscopy. Our results indicate that the semiconductors deposit onto the AuNP surface by surface limited electrochemical reactions.