Electrostatically assembling 2D hierarchical Nb2CTx and zifs-derivatives into Zn-Co-NC nanocage for the electrochemical detection of 4-nitrophenol

Construction of high-sensitive analytical platform to monitor organic pollutants in the environment is of significance. Nitrophenol is toxic organic pollutant, causing serious damage to biosphere. Herein, a simple self-assembled method was proposed to design a novel heterostructure (MXene/ZIF) composed of Nb2CTX and Zn-Co-ZIFs derived bimetallic Zn, Co embedded N-doped carbon (Zn-Co-NC) nanocage. The Nb2CTX/Zn-Co-NC composite modified electrodes were applied for the electrochemical detection of 4-nitrophenols (4-NP). SEM images revealed that the insertion of Zn-Co-NC can effectively avoid Nb2CTx from restacking. EDS and XPS demonstrated the successful synthesis of bimetallic Zn, Co embedded N-doped carbon nanocage. Excellent conductivity and large specific surface area of Nb2CTx as well as superior catalytic activity of Zn-Co-NC nanocage enhance the electrochemical performance of Nb2CTx/Zn-Co-NC sensor. Under optimal conditions, the achieved wide linear range was 1 mu M to 500 mu M. The low detection limit of 0.070 mu M with high sensitivity of 4.65 mu A mu M-1 cm(-2) was obtained. Furthermore, the Nb2CTx/Zn-Co-NC sensor holds outstanding selectivity and stability. Therefore, the innovative structure and excellent properties of MXene/ ZIF make them alternative materials for various electrochemical sensors for the detection of other toxic organic pollutants.