Facile synthesis of hierarchical microsphere-like layered double hydroxide for non-enzymatic selective detection of dopamine

Abstract

Layered double hydroxides (LDHs) are layered materials belonging to anionic clay family, have attracted attention for surface modification of electrodes for the electrochemical applications. Herein, we synthesized stable microsphere-like hierarchical structures of Mg-Al LDH using one-step surfactant free solvothermal method. The XRD pattern confirms the hydrotalcite-like LDH structure. The SEM images showed the 3D microspheres with flower-like structures with highly porous features visible at higher magnification. TEM images also confirmed the network of nanosheets interconnected with each other. Electrochemical studies showed that the microsphere like LDH material modified electrode exhibited enhanced electrochemical performance towards electrooxidation of dopamine with a linear response range from 2-100 μM and high sensitivity with low detection limit of 0.216 μM. The better results are due to its peculiar hierarchical structures with more exposure of active sites and fast electron transfer pathway. Therefore, this work provides a simple and feasible method for synthesizing Mg-Al LDH structures as a material for modifying electrodes for the electrochemical sensing application.