Improvement of remediation ability of copper-contaminated soil by plant microbial fuel cell based on PANI-PDA anode modification

Abstract

This study investigates the enhancement of soil remediation and power generation capacity of plant microbial fuel cells (PMFCs) using a polyaniline-polydopamine (PANI-PDA) modified carbon felt (CF) anode, so as to address the low efficiency of PMFCs in treating copper-contaminated soil and generating renewable energy. An experimental PMFC system was established using potted epipremnum aureum and copper-contaminated soil. The PANI-PDA/CF anode was prepared by solution impregnation method and were characterised by scanning electron microscopy (SEM) and BET tests. The performance of the modified anode was evaluated through copper removal rates, electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV). Results showed that the PANI-PDA/CF anode significantly increased the specific surface area by 489.84 times compared to the unmodified CF anode. The copper removal rate reached 90.53 %, which was 38.1 % higher than that of the conventional CF anode. The maximum power and current density of the PMFC with a PANI-PDA/CF anode were 0.1 mW·m⁻² and 6.28 mA·m⁻², and the steady-state output voltage was 15.47 mV, representing an 837.6 % increase over the unmodified CF anode. The use of PANI-PDA composite material for anodic modification effectively enhances the soil remediation capability and power generation performance of PMFCs, offering a promising approach for the remediation of heavy metal-contaminated soils and renewable energy production.