High-Flux Solar-Driven Thermochemical Dissociation of CO_2 and H_2O Using Nonstoichiometric Ceria ud

摘要

Because solar energy is available in large excess relative to current rates of energy consumption,udeffective conversion of this renewable yet intermittent resource into a transportable anduddispatchable chemical fuel may ensure the goal of a sustainable energy future. However, lowudconversion efficiencies, particularly with CO_2 reduction, as well as utilization of preciousudmaterials have limited the practical generation of solar fuels. By using a solar cavity-receiverudreactor, we combined the oxygen uptake and release capacity of cerium oxide and facile catalysisudat elevated temperatures to thermochemically dissociate CO_2 and H_2O, yielding CO and H_2,udrespectively. Stable and rapid generation of fuel was demonstrated over 500 cycles. Solar-to-fueludefficiencies of 0.7 to 0.8% were achieved and shown to be largely limited by the system scaleudand design rather than by chemistry.ud