Disposable nanodiamond/graphene-based electrochemical sensor for determination of rhodium and platinum in electroplating process

Abstract

This study introduces a novel disposable sensor platform for the first time by utilizing a nanodiamond-modified screen-printed graphene electrode (ND/SPGE) to achieve highly sensitive and selective determination of rhodium (Rh^II) and platinum (Pt^II) ions in industrial electroplating solutions. The ND/SPGE synergistically enhances electron transfer and surface interaction with target ions, allowing differential pulse anodic stripping voltammetry (DPASV) to obtain detection limits (LOD = 3S/N) of 0.35 ppm for Rh^IIand 0.52 ppm for Pt^IIwith linear responses in the ranges of 7.5–75 ppm for Rh^IIand 12.5–85 ppm for Pt^II. The sensor exhibits excellent selectivity in the presence of common interfering ions and demonstrates high accuracy with acceptable recovery (95 % and 105 %) and reproducibility (RSD < 5 %). These results highlight the potential of employing a ND/SPGE sensor as a reliable device for real-time monitoring and quality control of Rh^IIand Pt^IIconcentrations in industrial electroplating processes. Therefore, this work offers a practical, cost-effective sensing platform for in-situ monitoring of precious metals in plating operations, aligning with the need for sustainable and efficient process control in metal finishing industries.