A method of desorbing CO2 from a CO2-containing liquid solvent, comprising: providing a liquid solution comprising CO2; contacting the liquid to a porous anodized aluminum surface or porous anodized titanium surface while increasing the temperature or reducing the pressure of the liquid solution; and separating desorbed CO2 gas from the liquid solution. A desorption composition is provided comprising: an anodized aluminum substrate coated with a porous alumina layer and a functionalized surface and characterizable by an infrared absorption near 1712 cm−1 and a Raman band near 530 cm−1.