2D Transition Metal Carbides (MXenes) for Carbon Capture

Global warming caused by burning of fossil fuels is indisputably one of mankind's greatest challenges in the 21st century. To reduce the ever-increasing CO₂ emissions released into the atmosphere, dry solid adsorbents with large surface-to-volume ratio such as carbonaceous materials, zeolites, and metal-organic frameworks have emerged as promising material candidates for capturing CO₂ . However, challenges remain because of limited CO₂ /N₂ selectivity and long-term stability. The effective adsorption of CO₂ gas (≈12 mol kg^-1 ) on individual sheets of 2D transition metal carbides (referred to as MXenes) is reported here. It is shown that exposure to N₂ gas results in no adsorption, consistent with first-principles calculations. The adsorption efficiency combined with the CO₂ /N₂ selectivity, together with a chemical and thermal stability, identifies the archetype Ti₃ C₂ MXene as a new material for carbon capture (CC) applications.