In-situ encapsulation of oil soluble carbon nanoclusters in ZIF-8 and applied as bifunctional recyclable stable sensing material of nitrofurazone and lysine and fluorescent ink

Abstract

Metal-organic frameworks (MOFs) are porous materials consisting of organic ligands and metal ions/clusters through coordinate bonds, which have wide applications in the research fields such as sensing, catalysis, and adsorbents. On the other hand, as an emerging carbon nanomaterial with low toxicity and chemical inertia, carbon nanoclusters (CNCs) have received a lot of research interest. In this work, an oil soluble CNC was introduced into Zeolitic imidazolate framework-8 (ZIF-8) through in-situ encapsulation strategy to form hybrid material CNCs@ZIF-8 (1). 1 has been characterized by PXRD, FT-IR, Transmission electron microscopy (TEM) and photo-luminescent characterizations. Strong fluorescence emission at 450 nm for 1 can be observed when excited at 380 nm. Remarkably, the structure and fluorescence emission of 1 can maintain unchanged after soaking in different DMA, DMF, ethyl alcohol solvent and adding different targeted objects. Photo-luminescent studies show that 1 can be used as highly sensitive and selective “turn-off” fluorescent probe for antibiotic nitrofurazone (Ksv: 2.26 × 105 M−1 and detection limit: 0.0229 µM). On the other hand, 1 shows highly sensitive and selective “turn-on” response to lysine (KBH: 1.99 × 106 M−1 and detection limit: 0.0096 µM). Additionally 1 also exhibits good recyclable detection performance, after four numbers of detection cycles, the detection efficiency of nitrofurazone and lysine still can reach 93.86% and 88.82%, respectively. Further, in the UV-vis light excited at 365 nm, the fluorescent ink based on 1 with the addition of lysine can be observed in naked eye. As a result, 1 could be applied as a bifunctional recyclable stable sensing material for highly sensitive detection of nitrofurazone and lysine and fluorescent ink using 1 with the addition of lysine.