Investigation on synthesis of Y2O3/ZrO2 co-stabilized Cu/Ca composites and their thermochemical energy storage properties
Cu/Ca-based thermochemical energy storage presents a novel hydrogen storage method that effectively addresses excess power consumption.However,the effectiveness of Cu/Ca composites in carbonation decreases significantly after multiple cycles,limiting their practical use.To address this issue,we employed a stabilizer modification method to improve the performance of Cu/Ca composites.First,Cu/Ca composites were prepared using the Pechini method and stabilized with different stabilizers,then evaluated in a triple-packed-bed reactor.Experimental results showed that composites modified with stabilizers maintained excellent oxidation properties over 10 cycles,with oxidation conversions consistently above 90%.Among the stabilizers tested,Y2O3 significantly improved the carbonation conversion of the composites compared to CeO2 and MgO.Specifically,the 5Y-Cu-Ca composite,with a Y2O3/CaO/CuO molar ratio of 5∶47.5∶47.5,displayed an initial carbonation conversion of 74.6%,which decreased to 54.1%after 10 cycles.To further improve the carbonation performance of Y2O3-stabilized Cu/Ca composites,we adopted a dual-stabilization strategy by incorporating ZrO2 as a second carrier and co-doping it with Y2O3.The most effective Y2O3/ZrO2-stabilized Cu/Ca composites,with a molar ratio of 2∶1,achieved an initial carbonation conversion of 81.6%,dropping to 70.5%after 10 cycles,retaining 86%of its initial activity.In summary,the Cu/Ca composites developed in this study hold great potential for the practical application of Cu/Ca-based thermochemical energy storage technology.
energy storagechemical reactionchemical loopingstabilizer