One step laser-induced Fe3O4 loaded 3D graphene electrode for electrochemical sensing and supercapacitor applications

In this study, a novel one-step synthesis method is proposed for self-supported electrodes by fabricating Fe 3 O 4 loaded three-dimensional graphene through laser-induced pyrolysis (Fe 3 O 4 -LIGE). This electrode offers the advantages including high sensitivity, straightforward manufacturing process, cost-effectiveness, and environmentally benign, making it highly suitable for large-scale industrial production. Subsequently, a portable electrochemical sensor and a flexible supercapacitor were constructed based on Fe 3 O 4 -LIG as active material. The Fe 3 O 4 -LIGE demonstrated a significant increased electrochemically active area for adsorption, coupled with the reduced electron transfer resistance. This combination resulted in an increased number of active sites for the electrochemical reaction. Furthermore, the portable electrochemical sensor based on Fe 3 O 4 -LIGE can be utilized for the sensitive detection of chloramphenicol, which was further applied to the real honey and pork samples with a detection range from 10.0 nmol/L to 5.0 mmol/L and a detection limit of 3.1 n mol/L. Additionally, the flexible supercapacitors constructed from Fe 3 O 4 -LIGE exhibited an excellent reversibility and stability, achieving a specific capacitance of 12.07 mF/cm 2 at a current density of 0.05 mA/cm 2 , which was superior to the capacitance of most previously reported LIG-based devices. In summary, both the electrochemical sensors and the supercapacitors based on Fe 3 O 4 -LIGE demonstrated excellent performances. This innovate and rapid electrode preparation method may pave the way for large-scale fabrication of flexible electronics.