A Novel One-Step Electrochemical Sensor Utilizing Au–Ni Nanoparticles Supported on Etched MOF Nanocomposite for Rapid and Highly Sensitive 3–Nitrophenol Detection

An electrochemical sensor utilizing Au-Ni@ etched metal-organic framework (etched MOF) on a glassy carbon electrode (GCE) was constructed for ultrasensitive detection of 3-nitrophenol (3-NP). The Au-Ni@etched MOF in situ nanocomposite was synthesized via a simple one-step process that combines the electrochemical etching of Ni-hemin MOF with the simultaneous electrodeposition of Au-Ni bimetallic nanoparticles. The etched MOF not only provides abundant active sites for adsorbing 3-NP, but also serves as a supporter for loading Au-Ni bimetallic nanoparticles. This innovative design endows the electrochemical sensor with exceptional electrocatalytic activity towards 3-NP, achieving a low detection limit of 0.015 μM over the ranges of 0.06 ∼ 10 μM and 10 ∼ 200 μM. Moreover, the electrochemical sensor also shows excellent sensitivity, repeatability, and stability in 3-NP detection. This method offers a highly sensitive electrochemical strategy for accurately assaying 3-NP in water samples and opens new avenues for the application of MOF derivatives in electrochemical platforms.