Pengaruh Variasi Pencil Lead Electrode (PLE) terhadap Deteksi Ion Logam Pb (II) menggunakan Modifikasi MnO2 Metode Voltametri Siklik

This study is motivated by the limited research on modified pencil lead electrodes in electrochemical detection, despite their significant potential as simple, low-cost, and environmentally friendly heavy metal sensors. The aim of this research is to evaluate the performance of MnO₂/pencil lead electrode (MnO₂/PLE) with variations in pencil hardness—2B, B, and HB—in detecting K₃[Fe(CN)₆] and Pb²⁺ ions using cyclic voltammetry. The electrodes were modified using the drop-casting method, and voltammogram data were analyzed based on current and redox potential values. The results show that MnO₂/PLE (2B) demonstrated the best performance among the variants. This is attributed to the synergy between the electrocatalytic properties of MnO₂ and the high graphite content of the 2B pencil, which enhances conductivity and electrochemical response. MnO₂/PLE (2B) proved effective in detecting Pb²⁺ ions, making it a strong candidate for use as an electrochemical heavy metal sensor. The implications of this study contribute to the literature on modified carbon-based sensors and open opportunities for the development of portable, low-cost sensors for environmental monitoring.