Facile synthesis of carbon nitride quantum dots as a highly selective and sensitive fluorescent sensor for the tetracycline detection.

Ruining Bai,Heli Sun,Anzhong Peng,Jieli He,Peng Jin,Jingwei Li

doi:10.1039/d1ra04272f

Abstract

Enhanced blue fluorescent carbon nitride quantum dots (g-C3N4QDs) were synthesized by a simple solvothermal “tailoring” process from bulk g-C3N4 and analyzed by various characterization methods. The as-obtained g-C3N4QDs were successfully applied in the determination of tetracycline (TC) with a good linear relationship in the range of 0.23–202.70 μM. The proposed fluorescent sensor shows excellent stability, good repeatability, high selectivity and outstanding sensitivity to TC with a low detection limit of 0.19 μM. The fluorescence quenching mechanism of g-C3N4QDs with TC was mainly governed by static quenching and the inner filter effect. The method was successfully applied to monitor TC in tap water and milk powder samples.

Highlights

Since its re-discovery in 1990s, graphite carbon nitride (g-C3N4) as a metal-free semiconductor material has been widely explored and used in sensing,[1,2,3,4,5,6] catalysis,[7,8] uorescence imaging,[9,10] and cancer treatment[11] due to its unique electronic structure, excellent chemical and thermal stability, and good biocompatibility
transmission electron micrographs (TEM) and high resolution TEM were employed to observe the morphology of g-C3N4QDs
The diffraction peaks of g-C3N4QDs are in good agreement with those of bulk g-C3N4, indicating that they have the same basic crystal structure

Summary

Introduction

Since its re-discovery in 1990s, graphite carbon nitride (g-C3N4) as a metal-free semiconductor material has been widely explored and used in sensing,[1,2,3,4,5,6] catalysis,[7,8] uorescence imaging,[9,10] and cancer treatment[11] due to its unique electronic structure, excellent chemical and thermal stability, and good biocompatibility. Researchers have developed various types of QDs including metallic QDs,[13] nonmetallic QDs,[14] and composite QDs15 among others and applied them in electroluminescence devices, solar cells, photocatalysis, imaging and sensing based on their extraordinary optical properties: electrochemiluminescence, phosphorescence, and uorescence.[16] exploration of g-C3N4QDs may provide the promising properties and applications of g-C3N4 materials.

Objectives

Results

Conclusion