Synergetic effect of optimized β-Zn(OH)2/ZnO heterostructure towards electrochemical dopamine detection

Abstract

In this study, we have synthesized β-Zn(OH)2/ZnO heterostructures via a simple one-pot hydrothermal method followed by calcination at different temperatures under air for electrochemical dopamine (DA) detection. We found that the synergetic effect between optimized β-Zn(OH)2 and ZnO phases in β-Zn(OH)2/ZnO heterostructures boosts electrocatalytic activity. Moreover, β-Zn(OH)2/ZnO heterostructures calcined at 300 °C (i.e.,β-Zn(OH)2/ZnO300) showed enhanced electrochemical activity towards DA oxidation due to its larger electrochemical active surface area and higher adsorption capacity compared to other β-Zn(OH)2/ZnO heterostructures and ZnO. Additionally, β-Zn(OH)2/ZnO300 heterostructures demonstrated remarkable DA selectivity in the presence of over eight biomolecules, achieving rapid detection response in less than 10 seconds with a low detection limit of 0.17 nM and 1.0 nM within a linear range of (1.75–263 nM) and (263–1300 nM), respectively. Moreover, β-Zn(OH)2/ZnO300 heterostructures showed remarkable reproducibility (98.8 %), high stability (98.1 %), and real-time DA detection in human urine samples with a recovery rate ranging from 95.9 % to 103.2 %. Therefore, β-Zn(OH)2/ZnO heterostructures, especially those optimized under 300 °C, possess great potential for electrochemical applications, particularly in DA detection.