Composite MOF mixture as volatile organic compound sensor - A new approach to LMOF sensors

Five luminescent metal-organic frameworks (LMOFs) were synthesized solvothermally to investigate fluorescent enhancement and/or quenching effects in the solid state in the presence of a series of volatile organic compounds (VOCs). Each of the MOFs was characterized with powder X-ray diffraction directly after synthesis, activation, and with emission/excitation studies. Three of the LMOFs, LaBTB (BTB = 1,3,5-tris(4-carboxyphenyl)benzene acid), ZrPDA (PDA = 1,4-phenyldiacrylic acid), and UiO-66-NH2, were mixed and exposed to a series of VOCs to show the feasibility of solid mixtures in creating fingerprint-like spectroscopic regions for detection and identification of VOCs. This new strategy increases signal discrimination and dilutes effects of π-stacking on quantum yields.