Interfacial engineering Pb skin-layer at Rh surface to promote ethanol electrooxidation into CO2 in alkaline media

Rh is recently regarded as the promising electrocatalyst for ethanol oxidation into CO2 due to its high activity of splitting C–C bond, whereas the further oxidation of as-generated C1 species (CO and CHx) is pretty sluggish at Rh surface. To solve this, here the oxophile Pb skin-layer is inhabited at Rh nanoparticles to obtain the Pb@Rh core-shell structure with controllable Pb coverage (θPb), expecting to tune the surface reactivity of ethanol oxidation reaction (EOR) according to the Langmuir-Hinshelwood Mechanism as well as the strain effect. Fortunately, the as-obtained Pb@Rh/C catalysts indeed significantly enhance the catalysis performance of EOR, the optimal mass activity is ca. 1450 mA mg-1 metal when θPb is ca. 0.53 (Pb0.53@Rh), being ca. 13 times higher than pristine Rh catalyst. Meanwhile, as much as ca. 57% of the initial EOR current remains even after a 20,000-s durability measurement. And the apparent C1 pathway faraday efficiency (CO2 selectivity) is also estimated to be ca. 21% at Pb0.53@Rh surface. This work can provide a simple and promising protocol to tune the surface reactivity by interfacial engineering manipulation.