Escaping from Sabatier principle by introducing a confined environment: A case study on phenylacetylene semi-hydrogenation over nickel-based catalysts

The Sabatier principle defines the criteria for catalytic optimization with moderate binding energies between active component and support/gases; unfortunately, how the parameters within Sabatier profile determine the reaction performance is still lacking. Herein, using phenylacetylene semi-hydrogenation over nickel (Ni) as a probe, we show that styrene formation versus reaction temperature exhibits a trapezoid-shaped profile following Sabatier principle, with the inclination angle of ascending regime (αAsc.) greatly modified by Ni size (dVA, Ni; αAsc.∼[dVA, Ni]5∼0) while the declining regime (βDec.) was independent of dVA, Ni (βDec.∼[dVA, Ni]0) and was determined independently by reactant activation and product desorption. More interestingly, the length of the plateau region (l) was greatly promoted by confined environment. All these findings were determined from a systematic kinetic study of Ni-decorated NU-1000 and carbon nanotube reaction systems. This work would certainly deepen people's understanding on selective hydrogenation and pave the way for catalyst design from an atomic perspective.