Activated Hollow and Solid Carbon Spheres for Enhanced Removal Efficiency of Pharmaceutical Pollutants and Heavy Metals in Water

Heteroatom-doped carbons are emerging candidates for metal-free catalysis, photocatalysis, and pollutant removal. Herein, we report the synthesis of N-doped solid (CS) and hollow carbon spheres (CNB) via a modified Stöber’s method. TEM, Raman, and XPS characterization techniques demonstrated a well-constructed N-doped sp2/sp3 hybridized carbons scaffold. Both CNB and CS nanospherical carbons have shown a high surface area of 360 and 400 m2/g, respectively, making them ideal candidates for the adsorption of pharmaceutical pollutants (ciprofloxacin and ibuprofen) and heavy metals (Pb and Cr) from wastewater. These materials have good interfacial interaction with the adsorbate and generate the proper medium to facilitate fast and efficient remediation. The highest surface adsorption (96% in 30 min) was observed for ibuprofen by CS. Interestingly, CNB was more selective for heavy metals at lower concentrations, while CS showed high surface adsorption at higher concentrations. Graphical abstract: [Figure not available: see fulltext.].