Adsorption heat pump

An adsorption heat pump that uses carbon dioxide as refrigerant,

• wherein a metal-organic framework including a metal ion and one or a plurality of organic ligands is used as an adsorbent, and
• at least one of the organic ligands is represented by
• (where R1 to R15 are each independently selected from an alkyl group, an aryl group, an alkoxyl group, an alkene, an alkyne, a phenyl group, a substituted group thereof, a sulfur-containing group, a silicon-containing group, a nitrogen-containing group, an oxygen-containing group, a halogen, a nitro, an amino, a cyano, a boron-containing group, a phosphorus-containing group, a carboxylic acid, an ester, H, NH2, CN, OH, ═O, ═S, Cl, I, F,
• (where x is 1, 2, or 3),
• R16 to R18 may be present or absent, and if present, R16 to R18 are selected from
• an alkyl group or cycloalkyl group containing 1 to 20 carbon atoms,
• an aryl group containing 1 to 5 phenyl rings,
• an alkyl amine, aryl amine, diazo, or alkyl amide containing an alkyl group or cycloalkyl group containing 1 to 20 carbon atoms or an aryl group containing 1 to 5 phenyl rings, and
• —C≡C—).