A Recyclable Metal–Organic Framework as a Dual Detector and Adsorbent for Ammonia

Recyclable materials for simultaneous detection and uptake of ammonia (NH 3 ) are of great interest due to the hazardous nature of NH 3 . The structural versatility and porous nature of metal–organic frameworks (MOFs) make them ideal candidates for NH 3 capture. Herein, the synthesis of a water‐stable and porous 3‐dimensional Cu II ‐based MOF ( SION‐10 ) displaying a ship‐in‐a‐bottle structure is reported; the pores of the host SION‐10 framework accommodate mononuclear Cu II ‐complexes. SION‐10 spontaneously uptakes NH 3 as a result of two concurrent mechanisms: chemisorption due to the presence of active Cu II sites and physisorption (bulk permanent porosity). The color of the material changes from green to blue upon NH 3 capture, with the shifts of the UV/Vis absorption bands clearly seen at NH 3 concentrations as low as 300 ppm. SION‐10 can be recovered upon immersion of SION‐10⊃NH 3 in water and can be further reused for NH 3 capture for at least three cycles.