The success of MOFs has driven their development as a new tool for sensing analytes including toxic chemicals. [19][20][21] The MOF sensors can be applied in both environmental and biological systems. [22] The MOF sensor field has been established with the development of sensors for different metal ions, anions, and molecules. [23,24] The potential application of MOF sensors to the detection of heavy metal ions, toxic anions, and other hazardous species is of great interest. [25,26] Specifically, luminescence technology has allowed the roles of various MOF sites in analyte capture to be easily studied. [27][28][29] The precise use of MOFs is potentially a good tool for analyte detection. Furthermore, MOFs have been established as potential materials for selective, fast, and portable tools for sensing toxic chemicals, with the advantage of light-emitting properties. [30,31] Interestingly, these sensing models can operate in water and are pH stable with high efficiency. [32] Furthermore, MOFs are wellknown materials for the degradation of toxic chemicals. [33,34] Several reports have been published on MOF sensors for toxicant chemicals, such as metal ions, anions, organic solvents, pesticides, nitroaromatic compounds (NACs), chemical warfare agents, [35] and others. [36][37][38] Some reviews have summarized applications of MOFs in sensing and detection probes for ions and volatile organic compounds, [39] and MOF sensors in pesticide detection and absorption with their classification. [40] Others have summarized and analyzed interactions between hazardous compound adsorbates and MOFs. [41,42] The stability and applications of MOFs have been summarized by the research groups of Ding and coworkers. [43] Pehlivan and et al. summarized the role of fluorescence resonance energy transfer in elucidating molecular interactions utilized in biosensing tools. [44,45] Besides luminescence sensing, the reviewers summarized the progress of MOFs relevance in the various area including environment and medical science. [46] Recently, Liu and coworkers summarized the progress of MOFs and discussed the remaining challenges in drug delivery, [47] Garcia and coworkers studied and compared the MOFs as photocatalysts with common inorganic photocatalysts, [48] and Manos and coworkers studied and summarized MOFs challenges and prospects for ion-exchange and sorption applications. [49] Despite these meaningful reviews, the factors responsible for signal changes, mechanisms, and limits of detection have Mechanistic studies of materials able to detect hazardous and toxic chemicals, such as common organic solvents, pesticides, and nitroaromatic compounds (NACs), are critically important owing to the threat they pose to humans and the environment. Recently, porous luminescent metal-organic frameworks (MOFs) with multifunctional sites, high surface areas, and structural tunability have emerged as sensory devices for the detection of hazardous and toxic chemicals. Herein, recent progress regarding the mechanistic behavior of MOF sensors in the det...