Metal-Organic Framework Co-MOF-74-Based Host-Guest Composites for Resistive Gas Sensing

摘要

Increasing demands in the field of sensing, especially for gas detection applications, require new approaches to chemical sensors. Metal organic frameworks (MOFs) can play a decisive role owing to their outstanding performances regarding gas selectivity and sensitivity. The tetrathiafulvalene (TTF)-infiltrated MOF, CoMOF-74, has been prepared following the host guest concept and evaluated in resistive gas sensing. The Co-MOF-74-TTF crystal morphology has been characterized via X-ray diffraction and scanning electron microscopy, while the successful incorporation of TTF into the MOF has been validated via X-ray photoemission spectroscopy, thermogravimetric analysis, UV/vis, infrared (IR), and Raman investigations. We demonstrate a reduced yet ample uptake of CO, in the pores of the new material by IR imaging and adsorption isotherms. The nanocomposite Co-MOF-74-TTF exhibits an increased electrical conductivity in comparison to Co-MOF-74 which can be influenced by gas adsorption from a surrounding atmosphere. This effect could be used for gas sensing.