Integration of optical fiber with sensitive thin films offers great potential for the realization of novel chemical sensing platforms. In this study, we present a simple design strategy and high performance of nanoporous metal–organic framework (MOF) based optical gas sensors, which enables detection of a wide range of concentrations of small molecules based upon extremely small differences in refractive indices as a function of analyte adsorption within the MOF framework. Thin and compact MOF films can be uniformly formed and tightly bound on the surface of etched optical fiber through a simple solution method which is critical for manufacturability of MOF-based sensor devices. The resulting sensors show high sensitivity/selectivity to CO2 gas relative to other small gases (H2, N2, O2, and CO) with rapid (< tens of seconds) response time and excellent reversibility, which can be well correlated to the physisorption of gases into a nanoporous MOF. We propose a refractive index based sensing mechanism for the MOF-integrated optical fiber platform which results in an amplification of inherent optical absorption present within the MOF-based sensing layer with increasing values of effective refractive index associated with adsorption of gases.
Kim, Ki-Joong, Lu, Ping, Culp, Jeffrey T., & Ohodnicki, Paul R. (2018). Metal–Organic Framework Thin Film Coated Optical Fiber Sensors: A Novel Waveguide-Based Chemical Sensing Platform. ACS Sensors, 3(2). https://doi.org/10.1021/acssensors.7b00808
@article{osti_1455424,
author = {Kim, Ki-Joong and Lu, Ping and Culp, Jeffrey T. and Ohodnicki, Paul R.},
title = {Metal–Organic Framework Thin Film Coated Optical Fiber Sensors: A Novel Waveguide-Based Chemical Sensing Platform},
annote = {Integration of optical fiber with sensitive thin films offers great potential for the realization of novel chemical sensing platforms. In this study, we present a simple design strategy and high performance of nanoporous metal–organic framework (MOF) based optical gas sensors, which enables detection of a wide range of concentrations of small molecules based upon extremely small differences in refractive indices as a function of analyte adsorption within the MOF framework. Thin and compact MOF films can be uniformly formed and tightly bound on the surface of etched optical fiber through a simple solution method which is critical for manufacturability of MOF-based sensor devices. The resulting sensors show high sensitivity/selectivity to CO2 gas relative to other small gases (H2, N2, O2, and CO) with rapid (< tens of seconds) response time and excellent reversibility, which can be well correlated to the physisorption of gases into a nanoporous MOF. We propose a refractive index based sensing mechanism for the MOF-integrated optical fiber platform which results in an amplification of inherent optical absorption present within the MOF-based sensing layer with increasing values of effective refractive index associated with adsorption of gases.},
doi = {10.1021/acssensors.7b00808},
url = {https://www.osti.gov/biblio/1455424},
journal = {ACS Sensors},
issn = {ISSN 2379-3694},
number = {2},
volume = {3},
place = {United States},
publisher = {American Chemical Society (ACS)},
year = {2018},
month = {01}}
