Application of CD and Eu3+ dual emission MOF colorimetric fluorescent probe based on neural network in Fe3+ detection

Abstract

A new highly fluorescent hybrid material (CD@Eu-MOF) was synthesized by encapsulating CD (Carbon Dots) prepared from citric acid and ethylenediamine on the basis of a metal-organic framework prepared from Eu3+ and 1,2,4-benzenetricarboxylic acid. The prepared composite not only maintains the excellent fluorescence properties of CD and Eu3+ respectively, but also forms a dual-emission fluorescence system, and the system has good stability in aqueous solution. It was further used as a novel fluorescent probe for the detection of Fe3+, which can effectively exclude the interference of other metal ions from the detection, and the intensity ratio of IEu/ICD of CD@Eu-MOF material has a good linear relationship with Fe3+ in the range of 1-200 μM. In this study, computer vision and BP (Back Propagation) neural network were used to train and fit the sample data, and it was verified that the actual fluorescence color of CD has a good linear relationship with Fe3+ concentration. In addition, the BP neural network also verified that the fluorescence spectrum data of CD@Eu-MOF also has a good linear relationship with Fe3+ concentration. This study provides a new method for the fabrication of ratio and colorimetric Fe3+ fluorescence sensors, and provides a feasible solution for the simple and visual detection of Fe3+ in the environment.