Ultra-efficient perfluorooctanoic acid capture enabled by a novel MOF-derived Cu/Zn bimetallic spherical porous carbon

Abstract

The efficient removal of perfluorooctanoic acid (PFOA) is challenging, as conventional monometallic MOFs and powdered activated carbons suffer from limited active sites, poor stability, or unfavorable morphologies. Herein, a novel spherical porous carbon (SPC) derived from a Cu/Zn-BTC bimetallic MOF was synthesized via glucose-assisted hydrothermal carbonization and high-temperature pyrolysis. Featuring high sphericity, uniform pore channels, and abundant bimetallic active sites, SPC exhibits enhanced PFOA adsorption performance and water stability. The optimized SPC(5-(Cu/Zn-BTC)) achieves a maximum adsorption capacity of 480 mg g⁻¹ (surpassing most reported materials), with pseudo-second-order kinetics and spontaneous exothermic adsorption behavior. The process is dominated by synergistic mechanisms, including Cu²⁺/Zn²⁺–carboxylate coordination (verified by XPS), electrostatic attraction under acidic conditions (supported by zeta potential analysis), and hydrophobic interactions. Notably, SPC retains high adsorption efficiency after five regeneration cycles due to robust structural stability. This material exhibits potential for application in the field of PFOA removal from aqueous systems.