© 2019 The Royal Society of Chemistry. To be considered a good CO 2 capture material for industrial applications, alkaline ceramics have to present several properties such as fast sorption and desorption kinetics, large sorption capacities, regenerability and stability, and a wide operating temperature range. In this sense, Li 4 SiO 4 fulfills some of these features, although it has some kinetic disadvantages at temperatures lower than 500 °C and under low CO 2 partial pressures. Herein, we show an easy an efficient way to synthesize a Fe-containing Li 4 SiO 4 solid solution (Li 4+x Si 1-x Fe x O 4 , with x ≤ 0.5); by a dry ball milling synthesis, with high CO 2 capture capacities. A synergic effect, between the microstructural features given by the proposed synthesis method and the iron content, improves the CO 2 capture exhibited by the material in different ways: (1) Li 4+x Si 1-x Fe x O 4 solid solution samples are able to trap large amounts of CO 2 between 200 and 650 °C. At 200 °C, the solid solution chemisorbs 11 wt% of CO 2 , the largest amount of CO 2 captured reported so far in the literature at this temperature; (2) iron containing samples diminish the CO 2 capture dependence on temperature; (3) CO 2 capture was considerably improved under low partial pressures of CO 2 and (4) iron redox properties enhanced the CO 2 capture, by using a low partial pressure of O 2 .
Lara-García, H. A., Ovalle-Encinia, O., Ortiz-Landeros, J., Lima, E., & Pfeiffer, H. (2019). Synthesis of Li <inf>4+: X</inf> Si <inf>1- x</inf> Fe <inf>x</inf> O <inf>4</inf> solid solution by dry ball milling and its highly efficient CO <inf>2</inf> chemisorption in a wide temperature range and low CO <inf>2</inf> concentrations. Journal of Materials Chemistry A, 4153-4164. https://doi.org/10.1039/c8ta12359d