Multi-active sites in situ formed on Schiff-base Pd(II)/Cu(II) self-assembly monolayer supported on graphene oxide: A simple protocol to enhance the catalytic activity

•Novel organometallic Pd(II)/Cu(II) catalytic monolayer supported on GO (GO@Apimp-Pd/Cu) was fabricated by self-assembly.•The multi-active centres in situ formed on the surface of organometallic catalytic monolayer.•GO@ Apimp -Pd1/Cu6.5 had a higher catalytic activity with turn over frequency (TOF) up to 307320 h-1 due to the ensemble synergistic of multi-active centres.