Highly active and durable chlorobenzene oxidation catalyst via porous atomic layer coating of Ru on Pt/Al2O3

Herein, we designed and fabricated a novel subnanometer Ru-coating Pt/Al2O3 catalyst (named RuPt-ALD) via atomic layer deposition (ALD), which showed an excellent capability of tuning catalysts' structure-property relationship for chlorobenzene (CB) oxidation. Subnanometer Ru clusters were separately decorated onto Pt nanoparticles, while leaving neighboring Pt surfaces exposed, which could effectively enhance the substrate-particles interaction by electron donation. RuPt-ALD provided optimal activity and selectivity, and a stable CB conversion of ∼98 % for 600 min at 200 °C in humid air, superior to bare Ru or Pt samples. Experimental verification and theoretical calculation identified that the relative lower barriers of CB adsorption and O2 dissociation on RuPt-ALD contributed to its stronger CB adsorption and appropriate oxygen activation capacity, which were the core factors for the excellent performance under humid feed. In addition, under dry feed, the desorption ability of Cl species was also a key factor affecting the performance of Pt-based catalysts.