Investigation on the Growth Mechanism of Cu MoS Nanotube, Nanoplate and its use as a Catalyst for Hydrogen Evolution in Water.

Cu MoS is a ternary transition-metal sulfide that shows great potential in the field of energy conversion and storage, namely catalytic H evolution in water and Li-, Na- or Mg-ion battery. In this work, we report on a growth mechanism of the single-crystalline Cu MoS nanotube from (NH ) MoS salt and Cu O nanoparticle. By probing the nature and morphology of solid products generated in function of reaction conditions we find that the crystalline Cu(NH )MoS nanorod is first generated at ambient conditions. The nanorod is then converted into Cu MoS nanotube under hydrothermal treatment due to the Kirkendall effect or a selective etching of the Cu MoS core. Extending the hydrothermal treatment causes a collapse of nanotube generating Cu MoS nanoplate. The catalytic activities of these sulfides are investigated. The Cu MoS shows superior catalytic activity to that of Cu(NH )MoS . Catalytic performance of the former largely depends on its morphology. The nanoplate shows superior catalytic activity to the nanotube, thanks to its higher specific electrochemical surface area.