Metal Organic Framework Compounds (MOFs) as Host Materials for Optically Switchable Complexes

Tracking the light-induced isomerization processes and the photostability of spiropyrans embedded in the pores of crystalline nanoporous MOFs via IR spectroscopy

“…[2] N To enable photoswitching in the solid state, metal-organic frameworks (MOFs) [7] have recently been applied as porous host materials not only for spiropyrans [8][9][10][11] but for various photochromic molecules. [12][13][14][15][16][17][18] MOFs are composed of inorganic nodes and organic linker molecules that form 3 D frameworks with potential voids. [7] These voids have been intensively exploited regarding various applicabilities.…”

Metal–Organic Frameworks as Hosts for Photochromic Guest Molecules

“…9,10 Feŕey et al investigated MOFs as hosts for drug molecule encapsulation. 11,12 In a different approach, we have started a while ago to incorporate photoswitchable complexes 13 and azo dyes 14 into different MOFs to obtain new materials with interesting optical properties. Because of its well-known photochromic behavior, that is, well-separated absorption bands in the UV/vis spectrum for the trans and cis isomers, 15 azobenzene (AZB) can act as a molecular switch, when illuminated with light.…”

“…However, the embedment of larger functional molecules is less investigated up to now. Several publications are concerned with the inclusion of precursor molecules in MOFs to obtain metal nanoparticles inside the MOF framework through decomposition of the guest molecules. , Férey et al investigated MOFs as hosts for drug molecule encapsulation. , In a different approach, we have started a while ago to incorporate photoswitchable complexes and azo dyes into different MOFs to obtain new materials with interesting optical properties. Because of its well-known photochromic behavior, that is, well-separated absorption bands in the UV/vis spectrum for the trans and cis isomers, azobenzene (AZB) can act as a molecular switch, when illuminated with light.…”

Structure and dynamics of guest molecules confined in a mesoporous silica matrix: Complementary NMR and PDF characterisation

“…[9][10][11][12] In this class of compounds the nitrosyl ligand can undergo photoinduced linkage isomerisation 13,14 resulting in changes of the colour and the refractive index of the compounds. Since the linkage isomerism is a molecular property these complexes are suitable candidates for embedding them into host materials such as silica gels 15 and metal-organic frameworks 16 or electrostatic attachment on surfaces. 17 The study of the prototype complex Na 2 [Fe(CN) 5 NO]$2H 2 O (sodiumnitroprusside, SNP) embedded in silica matrices showed that the properties of the metastable linkage isomers are independent of the pore and particle size.…”