fullerene-containing ammonium salt, attributed to an intramolecular PET process
from the excited singlet state of Tb
3+ complex to C 60 moiety. Similarly to the above
findings, the luminescence of [2]pseudorotaxane could be reversibly switched on/off
by the alternating addition of K
+ and 18C6.
The capability to operate the structure and function of nanodevices via external
stimuli is becoming a most attractive candidate for developing multifunctional
materials. Light stimulus represents a preferred external physical and chemical tool
for manipulating the function of the materials owing to its unique advantages of
instant action, high spatial and temporal resolution, and cleanness. Photochromic
materials are known to undergo reversible transformations by light between two
states with distinct properties [40–45]. Therefore, the integration of photochromism
into various devices has endowed the materials with intriguing photoresponsive
behaviors and more sophisticated functions. Possessing the ability of excellent
thermal stability and prominent fatigue resistance, diarylethene derivatives have
been extensively introduced into many systems for constructing optically responsive
materials [46]. Our group have successfully developed a [2]pseudorotaxane via
combining an unsymmetrical diarylperfluorocyclopentene (DAE) and a Eu
3+ -
containing complex of terpyridinyldibenzo-24-crown-8 (Fig. 13) [47]. The guest
molecule could exhibit reversible and stable photochromic properties, achieving the
interconversion between the ring-opened and ring-closed forms under alternate UVvis light irradiation. Benefiting from the excellent luminescence properties of Eu
3+ ,
the assembly displayed satisfactory luminescence, while the guest molecule kept the
ring-opened form. Exposing the pseudorotaxane to 365 nm UV light, $80% of the
fluorescence intensity of Eu
3+ was quenched, revealing an initiated resonance energy
Fig. 12 Competitive bonding-driven reversible luminescent lanthanide switch with the PET-ET
processes [39]
5 Photoluminescent Crown Ether Assembly
121
from the excited singlet state of Tb
3+ complex to C 60 moiety. Similarly to the above
findings, the luminescence of [2]pseudorotaxane could be reversibly switched on/off
by the alternating addition of K
+ and 18C6.
The capability to operate the structure and function of nanodevices via external
stimuli is becoming a most attractive candidate for developing multifunctional
materials. Light stimulus represents a preferred external physical and chemical tool
for manipulating the function of the materials owing to its unique advantages of
instant action, high spatial and temporal resolution, and cleanness. Photochromic
materials are known to undergo reversible transformations by light between two
states with distinct properties [40–45]. Therefore, the integration of photochromism
into various devices has endowed the materials with intriguing photoresponsive
behaviors and more sophisticated functions. Possessing the ability of excellent
thermal stability and prominent fatigue resistance, diarylethene derivatives have
been extensively introduced into many systems for constructing optically responsive
materials [46]. Our group have successfully developed a [2]pseudorotaxane via
combining an unsymmetrical diarylperfluorocyclopentene (DAE) and a Eu
3+ -
containing complex of terpyridinyldibenzo-24-crown-8 (Fig. 13) [47]. The guest
molecule could exhibit reversible and stable photochromic properties, achieving the
interconversion between the ring-opened and ring-closed forms under alternate UVvis light irradiation. Benefiting from the excellent luminescence properties of Eu
3+ ,
the assembly displayed satisfactory luminescence, while the guest molecule kept the
ring-opened form. Exposing the pseudorotaxane to 365 nm UV light, $80% of the
fluorescence intensity of Eu
3+ was quenched, revealing an initiated resonance energy
Fig. 12 Competitive bonding-driven reversible luminescent lanthanide switch with the PET-ET
processes [39]
5 Photoluminescent Crown Ether Assembly
121