Electrocatalytic Oxidation of Bisphenol A at a ZIF-8/Supramolecular Carbon Nitride Nanocomposite-Modified Interface

Abstract

The design of the working electrode interface is crucial for the efficiency and stability of electrocatalytic processes, especially in energy conversion and environmental sensing applications. This study presents the development of a robust electrocatalytically active zeolitic imidazolate framework and a supramolecular self-assembled carbon nitride (ZIF-8|S-CN)-modified interface by employing a controlled electrodeposition method. This technique addresses the constraints of the traditional drop-cast method by facilitating in situ exfoliation and uniform deposition, producing a continuous, homogeneous, and crack-free catalytic layer. Critical parameters, including the ZIF-8 to S-CN ratio, scan rate, and number of deposition cycles, were methodically tuned to improve interfacial characteristics. The optimized ZIF-8|S-CN-modified electrode exhibited markedly enhanced electrochemical performance for the oxidation of Bisphenol A (BPA), a common endocrine-disrupting compound. The improved interface demonstrated a 2.65-fold increase in oxidation current and a 54 mV negative potential shift, outlining the electrocatalytic activity of ZIF-8|S-CN toward BPA oxidation. Furthermore, surface modification with ZIF-8|S-CN resulted in a 1.29-fold larger electroactive surface area than that of the bare electrode. The developed interface achieved a detection limit of 70.05 nM, highlighting its capability for oxidizing trace levels of BPA in environmental samples, which enabled highly sensitive voltammetric estimation. This study emphasizes an adaptable interface engineering methodology that offers a reproducible, reusable, and stable interface for advanced electrochemical applications.