Carbon-neutral conversion of methane supported by Ni-(Rh, Co) bimetallic catalysts for low-temperature proton-conducting ceramic fuel cells

Ni-(Rh, Co) bimetallic catalysts anchored on BaZr0.4Ce0.4Y0.1Yb0.1O3-delta, the anode backbone of proton-conducting ceramic fuel cells, exhibit superior activity and stability during dry reforming of methane at low temperatures below 600 degrees C. 4Ni1M (4 wt% Ni, 1 wt% Rh or Co) are synthesized at the optimum calcination temperature of 500 degrees C that is obtained by identifying the characteristics of their particle size and interaction with the support. 4Ni1M show consistent structural properties with alloy formation and interact actively with CH4 and CO2. Under all operating conditions, the order of activity and durability is 4Ni1Rh > 4Ni1Co >> 5Ni (5 wt% Ni). Post-mortem analysis after the durability test shows that 4Ni1M have a close association with carbon (formation and removal) when exposed to CH4 and CO2, improving their carbon resistance. This demonstrates that alloying Rh or Co with Ni in the anode of proton-conducting ceramic fuel cells enables their carbon-neutral operation while maintaining high activity and durability.