Pengaruh pH Pada Penentuan Ion Logam Fe3+ Secara Anodic Stripping Voltammetry Menggunakan Pencil Lead Electrode Modifikasi Lapisan Tipis Emas

Abstract

Fe³⁺ metal ions have been electrochemically detected using a pencil lead electrode modified with gold thin layer. The modification of the gold thin layer is carried out by sweeping-potential electrodeposition using the cyclic voltammetry method. The purpose of this study was to determine the optimum pH conditions for measuring Fe³⁺ metal ions using HNO₃ as a supporting electrolyte. The pH optimization is carried out using the Anodic Stripping Voltammetry (ASV) method. This technique involves a pre-concentration step where Fe³⁺ is reduced to Fe⁰ on the electrode surface in HNO₃, followed by a stripping step in ASV where Fe⁰ is oxidized back to Fe³⁺. The results showed that HNO₃ with pH 1 is the optimum pH for measuring Fe³⁺ metal ions using Au/PLE electrodes with a test analyte concentration of 250 μM. The anodic peak of the Fe³⁺ metal ion appears at a potential of 0.55 V.