Here, we report the development of novel, highly effective CaO-based CO2 sorbents via a well-scalable and economic synthesis technique, viz. the re-crystallization of calcium and magnesium acetates in organic solvents. We successfully synthesized a material that possessed an excellent cyclic CO2 uptake (10.71 mmol(CO2) g(sorbent)−1 after 10 cycles), even under harsh, but practically relevant, regeneration conditions. To obtain such a high cyclic CO2 uptake, it was found to be crucial to mix the active component, CaO, and the high Tammann temperature support, MgO, on the nanometer scale. The synthesis technique developed only requires 8 wt% of MgO to effectively stabilize the cyclic CO2 uptake of the material. Furthermore, we established the influence of various synthesis parameters such as the molar ratio of Ca2+ to Mg2+ and the re-crystallization media on the sorbent's morphology and, in turn, cyclic CO2 uptake. Our best material exceeded the CO2 uptake (10th cycle) of limestone by 200%.