In this section we focus on the methods and materials used for CO2 capture and separation from other gases in industrial settings. Annual volumes of related publications from 2000 to 2021 are shown in Figure where patterns are similar to that for total publications related to CO2 sequestration and utilization (Figure ). Publication numbers were low prior to 2007, increased sharply afterwards, peaked in the early 2010s, and stabilized afterwards. The publication trends for CO2 separation and capture (Figure ) are more abrupt than the overall publication trends shown in Figure