Octahedral Pt–Ni Alloy Nanoparticles Decorated on 3D Interconnected Porous Carbon Nanosheets for Voltammetric Determination of Dihydroxybenzene Isomers

Ultrathin three-dimensional (3D) interconnected porous carbon nanosheets (PCNs) derived from Moringa oleifera barks (commonly known as the drumstick tree) with electrochemical (EC) sensor performance was employed as the carbon precursor. In this study, we described a simple one-step pyrolysis technique to generate hierarchical PCN using a high-temperature pyrolysis and KOH activation procedure. Using the microwave-solvothermal approach, platinum–nickel bimetallic octahedral nanoparticles were decorated on ultrathin 3D PCN (referred to as Pt–Ni@PCN). The morphological, structural, and EC properties of the Pt–Ni@PCN nanocomposite were well characterized. Using cyclic voltammetry and linear sweep voltammetry, the dihydroxybenzene (DHB) isomers hydroquinone, catechol, and resorcinol were identified individually as well as simultaneously. The screen-printed carbon electrode-modified nanocomposite [Pt–Ni@PCN/screen-printed carbon electrode (SPCE)] served as an outstanding electron (e^–)-transfer mediator for DHB isomer oxidation, yielding limits of detection of 0.0093, 0.0263, and 0.0529 μM, respectively. Also, the Pt–Ni@PCN/SPCE sensor has exceptional selectivity, long-term durability, reproducibility, repeatability, and anti-interference. Furthermore, the proposed sensor can be exploited to detect simultaneously environmental pollutants in river, lake, and tap water samples with good recovery rates.