Repurposing Coriandrum sativum L. powder into bifunctional graphene oxide decorated biochar material for efficient removal of emerging pollutants and sensing of uranyl ions.

Development in industrial and agricultural sector has increased the toxicity of natural water bodies due to the upsurge in pharmaceutical and pesticide usage, thereby attracting significant attention towards wastewater treatment. In this study, a highly porous graphene oxide modified Coriandrum sativum L. powder based biochar (GOCP) composite was synthesized, exhibiting bifunctional capabilities for both adsorption and sensing of pollutants. The obtained GOCP composite, with superior surface properties, was assessed for the adsorption of drug Ciprofloxacin (CF) and pesticide Bifenthrin (BF). The results demonstrated excellent adsorptive capacities of 15.974 mg/g for CF and 15.649 mg/g for BF using 15GOCP, owing to presence of abundant surface-active sites. The adsorption mechanism involves n-π /π-π interaction, hydrophobic interactions, hydrogen bonding, pore filling and predominantly electrostatic interactions. In addition, 15GOCP was investigated for its sensing ability and exhibited efficient detection of uranyl (UO22+) ions with detection limit of 1.21 μM. More importantly, the 15GOCP biochar composite retained substantial adsorptive capacity after five cycles, validating its aptitude for repeated use. Furthermore, the composite demonstrated astonishing removal and sensing performance in real water samples, establishing promising potential of the devised GOCP composite. This work provides a dual-purpose platform for removal and detection of contaminants in polluted water.