Functionalization of CO2‑Derived Carbon Support as a Pathway to Enhancing the Oxygen Reduction Reaction Performance of Pt Electrocatalysts

Proton-exchange membrane fuel cells (PEMFCs) hold promise for clean energy generation, but their commercialization is partially hindered by the sluggish oxygen reduction reaction (ORR) at the cathode, which relies on costly Pt electrocatalysts supported by petroleum-derived carbon. This study investigates a CO2-derived carbon (CO2–C) material as a sustainable alternative to petroleum-derived carbon and attempts to enhance the ORR performance of Pt electrocatalyst with the CO2–C support by pretreatment with hydrogen peroxide (H2O2) and potassium hydroxide (KOH) solutions. Based on physical characterization results, both KOH and H2O2 pretreatments of CO2–C increased the Brunauer–Emmett–Teller (BET) surface area and improved the metal–support interaction compared to untreated CO2–C. Electrochemical characterization revealed superior ORR performance of Pt/H2O2–CO2–C, exhibiting higher mass activity (142.8 mA mgPt –1) compared to Pt/CO2–C (102 mA mgPt –1), while Pt/KOH–CO2–C showed the highest specific activity (1503.8 μA cmPt –2) among the studied samples. Thus, Pt electrocatalysts with pretreated CO2–C support are presented as an alternative to conventional Pt/C catalysts toward sustainable and high-performance PEMFCs.