Quaternized Graphene for High‐Performance Moisture Swing Direct Air Capture of CO <sub>2</sub>
Isabella Nicotera, Apostolos Enotiadis, Cataldo Simari
Abstract
Abstract Nowadays, moisture‐swing adsorption technology still relies on quaternary ammonium resins with limited CO 2 capacity under ambient air conditions. In this work, a groundbreaking moisture‐driven sorbent is developed starting from commercial graphene flakes and using glycidyltrimethylammonium chloride for incorporation of CO 2 ‐sensitive quaternary ammonium functional groups. Boasting an outstanding CO 2 capture performance under ultra‐diluted conditions (namely, 3.24 mmol g −1 at CO 2 400 ppm and 20% RH), the functionalized sorbent ( f GO) features clear competitive advantages over current technologies for direct air capture. Notably, f GO demonstrated unprecedented moisture‐swing capacity, ease of regenerability, versatility, selectivity, and longevity. These distinctive features position the f GO as an advanced and promising solution, showcasing its potential to outperform existing methods for moisture‐swing direct air capture of CO 2 .