Synthesis of photoluminescent composite based on graphene quantum dot@ZIF-11: A novel sensor for extremely efficient nano-molar detection of CN

This report proposes a simple and very high sensitive photoluminescence sensor for the detection of fatal cyanide ion using a novel composite made from graphene quantum dots (GQDs) as luminescence quantum materials which was encapsulated successfully in zeolitic imidazolate framework)ZIF-11(as a stable porous carrier. Characterization methods such as TGA, TEM, SEM, XRD and IR have been utilized to identify the species. The detection method is based on the significant PL quenching signal of GQDs@ZIF-11 composite by increasing the concentration of cyanide ion. This sensor detected the CN- with wide linear range LDR (0.15 to 30 mu M), 0.95 % RSD and excellent limit of detection (LOD) of 14.5 nM. Interference study carried out in the presence of 19 different ions with good sensitivity toward cyanide ion. Also the study was performed on two real cyanide sample solutions which were extracted from apple seeds and bitter almonds. The good selectivity, high sensitivity, stability and wide linear response range made the sensor reliable and valuable compared to other previous ones.

Automated summary

This report presents a simple and highly sensitive photoluminescence sensor for detecting fatal cyanide ions using a novel composite material made from graphene quantum dots (GQDs) encapsulated in zeolitic imidazolate framework (ZIF-11). The sensor demonstrated excellent detection capabilities with a wide linear range, low relative standard deviation, and a very low limit of detection. It also showed good sensitivity towards cyanide ions in the presence of other interfering ions. Real cyanide samples from apple seeds and bitter almonds were successfully detected using this sensor. The reliable and valuable performance of this sensor makes it a promising candidate for cyanide ion detection.