Eco-friendly approach for the removal and simultaneous detection of cyanide toxins from drinking and wastewater sources.

The consumption of drinking water and wastewater with low concentrations of toxic cyanide ions (CN-) can result in bioaccumulation, posing a significant risk to human health and leading to sudden death. Thus, sensitive detection and selective removal approaches for ultra-trace concentrations of highly toxic CN- from water sources are of particular interest to a widening cohort of water purification researchers. In this study, we fabricated 3D hierarchy and face-centered cubic (fcc) surfaces of zirconium organic frameworks (ZOFs) that are decorated tightly with organic colorant dressers, enabling the fabrication of multi-functional captor/sensor microstructures (CSMs). The CSM structures can customize a wide range of functions of naked-eye detection, removal, and recovery of extremely toxic CN- in drinking and wastewater environments in a simultaneous, one-pot process. The visual CSM function was controlled via the modification of cubic fcc surfaces of ZOFs with hydrophobic colorant receptors, leading to the formulation of multi-functional capture centers, resembling branches, onto the entire surface scaffolds. Such CSM models provide sensitive and selective capture/trapping/removal and detection of CN- in diverse water sources and environments. The CSM models demonstrated significant capabilities in the selective and sensitive detection of CN- (48 ppt, parts per trillion) in water samples within seconds (40 s). Moreover, the CSM models demonstrate a high CN-adsorption capacity of 137.17 mg/g under optimal adsorption conditions. In terms of controlling CN-environmental waste, the chemical/physical features of CSM models (i.e., large surface area-to-volume ratios, heterogeneous active sites, uniform 3D geometries, and multifaced cubic surfaces) efficiently facilitate a stable CN-recovery process without structural degradation, despite rigorous chemical treatment across numerous cycles. The effective reusability of the CSM design in a wide range of drinking and wastewater sources fosters an eco-friendly approach for CN- waste management, minimizing its harmful release into the environment.