Monolith catalysts fabricated with the immersion-pyrolysis technique suffer the uncontrollable morphology of active component, leading to low conversion and reaction rates. Herein, we propose a strategy by introducing Co3O4 nanomicrostructure on Ni foam to induce the construction of porous flower-like PdO morphology. Investigations revealed the flower structure s originally formed during the solvent evaporation after immersing Co3O4/Ni in PdCl2 solution. The nanomicrostructure also restrained the spontaneous replacement of palladium ions to nickel atoms. Benefiting from these advantages, 0.51% PdO/Co3O4/Ni declared high catalytic reaction rate up to 9.44 mmol g(Pd)(-1) s(-1) for alpha-methylstyrene (AMS) hydrogenation in a stirring tank reactor (STR) at 40 degrees C and 0.5 MPa of H-2, 29.5 times superior to that of 5.99% PdOy/Ni. In a mass-transfer-enhanced rotating packed bed reactor, the modified monolith catalyst also exhibited slightly boosted AMS conversion and reaction rate than that in STR, demonstrating the flexible applicability prospects for various reactors.