Developing high-performance Ca-based materials that can work for long-term heat transfer and storage in concentrated solar power plants is crucial to achieve the large-scale conversion of solar photon fluxes to dispatchable electricity. This work demonstrates that a series of Mn, Zr co-doped CaCO3 nanomaterials with the 3D ordered macroporous (3DOM) skeletons are successfully prepared by a novel strategy of templated metal salt co-precipitation. The characterization results indicate that a majority of Zr and Mn are atomically dispersed into the highly-crystallized CaCO3 framework, whereas a minor amount of Mn is present in the form of CaMnO3 nanoparticles (NPs). The optimal 3DOM material made by templating with PS microspheres with a diameter of ≈350 nm, 3DOM-Ca80Mn10Zr10, shows a solar light absorptance of ≈74.1% and an initial energy storage density of 1706.4 kJ kg-1. Importantly, it gives an impressive energy storage density loss of < 6.0% and maintains above 1600 kJ kg-1 after 125 cycles. The density functional theory calculations reveal that the co-doping of Mn and Zr into the CaO crystal lattice offers a strong affinity to [Ca4O4] clusters, as a result, the anti-sintering of CaO NPs is significantly enhanced under high temperature.
Keywords: CaCO3; Ca‐looping; ordered macropores; photonic crystals; thermochemical energy storage.
© 2024 The Author(s). Advanced Science published by Wiley‐VCH GmbH.