TY - JOUR
T1 - Preparation of luminescent metal-organic framework films by soft-imprinting for 2,4-dinitrotoluene sensing
AU - Roales, Javier
AU - Moscoso, Francisco G.
AU - Gámez, Francisco
AU - Lopes-Costa, Tânia
AU - Sousaraei, Ahmad
AU - Casado, Santiago
AU - Castro-Smirnov, José R.
AU - Cabanillas-Gonzalez, Juan
AU - Almeida, José
AU - Queirós, Carla
AU - Cunha-Silva, Luís
AU - Silva, Ana M. G.
AU - Pedrosa, José M.
N1 - Publisher Copyright:
© 2017 by the authors. Licensee MDPI, Basel, Switzerland.
PY - 2017/8/25
Y1 - 2017/8/25
N2 - A novel technique for the creation of metal-organic framework (MOF) films based on soft-imprinting and their use as gas sensors was developed. The microporous MOF material [Zn2(bpdc)2(bpee)] (bpdc = 4,4′-biphenyldicarboxylate; bpee = 1,2-bipyridylethene) was synthesized solvothermally and activated by removing the occluded solvent molecules from its inner channels. MOF particles were characterized by powder X-ray diffraction and fluorescence spectroscopy, showing high crystallinity and intense photoluminescence. Scanning electron microscope images revealed that MOF crystals were mainly in the form of microneedles with a high surface-to-volume ratio, which together with the high porosity of the material enhances its interaction with gas molecules. MOF crystals were soft-imprinted into cellulose acetate (CA) films on quartz at different pressures. Atomic force microscope images of soft-imprinted films showed that MOF crystals were partially embedded into the CA. With this procedure, mechanically stable films were created, with crystals protruding from the CA surface and therefore available for incoming gas molecules. The sensing properties of the films were assessed by exposing them to saturated atmospheres of 2,4-dinitrotoluene, which resulted in a substantial quenching of the fluorescence after few seconds. The soft-imprinted MOF films on CA/quartz exhibit good sensing capabilities for the detection of nitroaromatics, which was attributed to the MOF sensitivity and to the novel and more efficient film processing method based on soft-imprinting.
AB - A novel technique for the creation of metal-organic framework (MOF) films based on soft-imprinting and their use as gas sensors was developed. The microporous MOF material [Zn2(bpdc)2(bpee)] (bpdc = 4,4′-biphenyldicarboxylate; bpee = 1,2-bipyridylethene) was synthesized solvothermally and activated by removing the occluded solvent molecules from its inner channels. MOF particles were characterized by powder X-ray diffraction and fluorescence spectroscopy, showing high crystallinity and intense photoluminescence. Scanning electron microscope images revealed that MOF crystals were mainly in the form of microneedles with a high surface-to-volume ratio, which together with the high porosity of the material enhances its interaction with gas molecules. MOF crystals were soft-imprinted into cellulose acetate (CA) films on quartz at different pressures. Atomic force microscope images of soft-imprinted films showed that MOF crystals were partially embedded into the CA. With this procedure, mechanically stable films were created, with crystals protruding from the CA surface and therefore available for incoming gas molecules. The sensing properties of the films were assessed by exposing them to saturated atmospheres of 2,4-dinitrotoluene, which resulted in a substantial quenching of the fluorescence after few seconds. The soft-imprinted MOF films on CA/quartz exhibit good sensing capabilities for the detection of nitroaromatics, which was attributed to the MOF sensitivity and to the novel and more efficient film processing method based on soft-imprinting.
KW - Metal-organic frameworks
KW - Gas sensors
KW - Soft-imprinting
KW - Nitroaromatics
KW - Explosive detection
UR - https://www.scopus.com/pages/publications/85028439437
U2 - 10.3390/ma10090992
DO - 10.3390/ma10090992
M3 - Article
C2 - 28841183
SN - 1996-1944
VL - 10
JO - Materials
JF - Materials
IS - 9
M1 - 922
ER -