A strong bimetal-support interaction in ethanol steam reforming

Abstract

The metal-support interaction (MSI) in heterogeneous catalysts plays a crucial role in reforming reaction to produce renewable hydrogen, but conventional objects are limited to single metal and support. Herein, we report a type of RhNi/TiO₂ catalysts with tunable RhNi-TiO₂ strong bimetal-support interaction (SBMSI) derived from structure topological transformation of RhNiTi-layered double hydroxides (RhNiTi-LDHs) precursors. The resulting 0.5RhNi/TiO₂ catalyst (with 0.5 wt.% Rh) exhibits extraordinary catalytic performance toward ethanol steam reforming (ESR) reaction with a H₂ yield of 61.7%, a H₂ production rate of 12.2 L h^-1 g_cat^-1 and a high operational stability (300 h), which is preponderant to the state-of-the-art catalysts. By virtue of synergistic catalysis of multifunctional interface structure (Rh-Ni^δ--O_v-Ti³⁺; O_v denotes oxygen vacancy), the generation of formate intermediate (the rate-determining step in ESR reaction) from steam reforming of CO and CH_x is significantly promoted on 0.5RhNi/TiO₂ catalyst, accounting for its ultra-high H₂ production.