A facile sonochemical route for the synthesis of MoS2/Pd composites for highly efficient oxygen reduction reaction.

For the alkaline fuel cell cathode reaction, it is very essential to develop novel catalysts with superior catalytic properties. Here, we report the synthesis of highly active and stable MoS2/Pd composites for the oxygen reduction reaction (ORR), via a simple, eco-friendly sonochemical method. The bulk MoS2 was first transformed into single and few layers MoS2 nanosheets through ultrasonic exfoliation. Then the exfoliated MoS2 nanosheets served as supporting materials for the nucleation and further in-situ growth of Pd nanoparticles to form MoS2/Pd composites via ultrasonic irradiation. Cyclic voltammetry and rotating disk voltammetry measurements demonstrate that as-prepared MoS2/Pd composites which provides a direct four-electron pathway for the ORR, have better electrocatalytic activity, long-term operation stability than commercial Pt/C catalyst. We expect that the present work would provide a promising strategy for the development of efficient oxygen reduction electrocatalyst. In addition, this study can also be extended to the preparation of other hybrid with desirable morphologies and functions.