Calcium looping, a CO₂ capture technique, may offer a mid-term if not near-term solution to mitigate climate change, triggered by the yet increasing anthropogenic CO₂ emissions. A key requirement for the economic operation of calcium looping is the availability of highly effective CaO-based CO₂ sorbents. Here we report a facile synthesis route that yields hollow, MgO-stabilized, CaO microspheres featuring highly porous multishelled morphologies. As a thermal stabilizer, MgO minimized the sintering-induced decay of the sorbents' CO₂ capacity and ensured a stable CO₂ uptake over multiple operation cycles. Detailed electron microscopy-based analyses confirm a compositional homogeneity which is identified, together with the characteristics of its porous structure, as an essential feature to yield a high-performance sorbent. After 30 cycles of repeated CO₂ capture and sorbent regeneration, the best performing material requires as little as 11 wt.% MgO for structural stabilization and exceeds the CO₂ uptake of the limestone-derived reference material by ~500%.

中文翻译：

---

通过优化CaO的结构特性及其有效的稳定性，可以生产出高容量的CO2吸附剂。

钙循环（一种CO ₂捕获技术）可能会提供一种人为的（即使不是短期的）解决方案来缓解气候变化，这是由人为的CO ₂排放量仍在增加所触发的。钙循环经济运行的关键要求是要获得高效的基于CaO的CO ₂吸附剂。在这里，我们报告了一种容易的合成路线，该路线可产生具有高度多孔的多壳形态的MgO稳定的空心CaO微球。作为热稳定剂，MgO最小化了烧结引起的吸附剂CO ₂容量的衰减，并确保了稳定的CO ₂吸收多个操作周期。基于电子显微镜的详细分析证实了组成的均一性，以及其多孔结构的特征，这些均一性被确定为生产高性能吸附剂的基本特征。经过30个重复的CO ₂捕获和吸附剂再生循环后，性能最佳的材料需要低至11 wt。％的MgO来稳定结构，并且比石灰石衍生的参考材料的CO ₂吸收量高出〜500％。