Sorbing materials, also known as sorbents, are materials used to absorb or adsorb liquids or gases. The process of sorption includes both: - **absorption**, where the substance is **taken up into the interior** of the sorbent, - **adsorption**, where the substance is **attracted to the surface** of the sorbent Sorbent materials used for [[Carbon Capture Use & Storage (CCUS) MOC]] are crucial in mitigating the effects of climate change. These materials work by absorbing CO2 from the atmosphere and then releasing it when needed, often through a process known as a **moisture swing**, where the material absorbs CO2 when dry and releases it when wet These materials are used in various CO2 capture technologies, including post-combustion capture, pre-combustion capture, oxy-fuel combustion, and direct air capture. The choice of sorbent material depends on the specific application and the conditions under which the capture process is carried out. 1. **[[Metal-Organic Frameworks - MOFs]] **: These are porous materials that have a high surface area and can selectively capture CO2. They are made up of metal ions or clusters coordinated to organic ligands. MOFs can be engineered to have specific properties, making them suitable for CO2 capture [[10](https://pubs.acs.org/doi/10.1021/acs.chemrev.7b00659)]. 2. **Amine-functionalized materials**: These materials have been widely studied for CO2 capture. The amine groups in these materials react with CO2 to form carbamates, which can then be decomposed to release the captured CO2 [[11](https://pubs.acs.org/doi/10.1021/acs.chemrev.7b00659)]. 3. **Carbon-based materials**: These include activated carbon, carbon nanotubes, and graphene-based materials. These materials have a high surface area and can be modified to enhance their CO2 capture capacity [[12](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 4. **Zeolites**: These are microporous, aluminosilicate minerals that have a high thermal stability and can selectively capture CO2 [[13](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 5. **Calcium oxide (CaO) and magnesium oxide (MgO)**: These materials can react with CO2 to form carbonates, which can then be decomposed to release the captured CO2. However, these materials suffer from a decrease in capture capacity over multiple cycles of capture and release [[14](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 6. **Polymeric materials**: These include polyamines and polyethyleneimine, which can be impregnated onto a support material to capture CO2 [[15](https://pubs.acs.org/doi/10.1021/acs.chemrev.7b00659)]. 7. **Ionic liquids**: These are salts in a liquid state that have a low vapor pressure, making them suitable for CO2 capture. They can be designed to have a high CO2 solubility and selectivity [[16](https://pubs.acs.org/doi/10.1021/acs.chemrev.7b00659)]. 2. **Hydrotalcite-like compounds (HTLcs)**: These are layered double hydroxides that can capture CO2 through a carbonation reaction. They have a high thermal stability and can be regenerated by heating [[17](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 3. **Silica-supported amines**: These materials have been shown to have a high CO2 capture capacity and can be regenerated by heating [[18](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 4. **Layered double hydroxides (LDHs)**: These are a type of ionic solids with a layered structure. They can capture CO2 through a carbonation reaction and can be regenerated by heating [[20](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 12. **Alkali metal carbonates**: These materials can react with CO2 to form bicarbonates. However, they require high temperatures to regenerate the captured CO2 [[21](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 13. **Alkali metal hydroxides**: These materials can react with CO2 to form carbonates. They also require high temperatures to regenerate the captured CO2 [[22](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 14. **Alkali metal oxides**: These materials can react with CO2 to form carbonates. They can be regenerated by heating but suffer from a decrease in capture capacity over multiple cycles of capture and release [[23](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 15. **Alkaline earth metal oxides**: These materials can react with CO2 to form carbonates. They can be regenerated by heating but also suffer from a decrease in capture capacity over multiple cycles of capture and release [[24](https://www.sciencedirect.com/science/article/pii/S2213343717303319)]. 16. **Transition metal oxides**: These materials can react with CO2 to form carbonates. They can be regenerated by heating but also suffer from a decrease in capture capacity over multiple cycles of capture and release [[25](https://www.sciencedirect.com/science/article/pii/S2213343717303319)].