Probing the active sites for water–gas shift over Pt/molybdenum carbide using multi-walled carbon nanotubes

•Pt/Mo2C/MWCNT has WGS kinetic parameters similar to those of Pt/Mo2C at 120°C.•Structure of the catalyst is Pt–Mo nanoparticles preferentially bound to Mo2C.•WGS rate per gram at 120°C increases with the fraction of the support surface covered by Pt–Mo nanoparticles.•Pt–Mo nanoparticles perform CO activation, while Mo2C performs H2O dissociation.