Direct methanol fuel cells (DMFCs) require efficient and economical anode catalysts to improve methanol electrooxidation reaction (MOR) performance. In order to develop a sustainable and cost-effective alternative for this process, we fabricated self-assembled monolayer (SAM) films on copper substrates utilizing bio-waste-derived clover leaf (CL, Trifolium repens L.) ethanolic extracts. The electrodes (Cu/CL-SAM) were fabricated by exposing the Cu samples to deaerated 1000 ppm CL solution (ethanol) for 24 h. The modified surfaces were examined by SEM, EDX, FTIR and contact angle analyses. Their MOR performance were evaluated using cyclic voltammetry (CV) and chronoamperometry (i–t) techniques in 0.1 M KOH solution in the presence of 1 M CH₃OH. After film formation, the contact angle increased from 63.13° to 85.18°, indicating that the organic layer altered the surface properties of copper. Electrochemical measurements showed a clear enhancement in catalytic activity. The anodic peak current density increased from 21.13 mA cm-2 on bare Cu to 34.84 mA cm-2 on the Cu/CL-SAM electrode. These results suggest that plant-derived SAM films can serve as a simple, low-cost and environmentally friendly strategy for improving Cu-based DMFC anodes.
Yüksel et al. (Sun,) studied this question.