Enhanced PPCP electrooxidation in pharmaceutical wastewater by cocatalyst modification over Ti-doped α-Fe2O3 electrodes.

• A cocatalyst loading strategy is proposed for wastewater electrochemical treatment. • The cocatalyst NiOOH accelerates the charge transfer, thus promoting water oxidation. • The increased reactive oxygen species promote the electrooxidation of organics. • The electrode shows great promise for pharmaceutical wastewater treatment. Acetaminophen (APAP), a common pharmaceutical and personal care product, is highly toxic and resistant to conventional wastewater treatment. Electrochemical oxidation is a promising technique for removing pharmaceuticals and personal care products (PPCPs), and the Ti-doped α -Fe 2 O 3 electrode is a low-cost alternative to noble-metal electrocatalysts. Herein, we present a novel cocatalyst loading strategy to enhance the electrocatalytic ability of the electrodes by loading a cocatalyst, NiOOH, by electrodeposition. The cocatalyst leads to a higher potential drop (97.7%) on the Helmholtz layer than the bare one (80.5%) and accelerates the charge transfer by ten. The increased production of reactive oxygen species during water activation further facilitates the electrooxidation of APAP, resulting in a threefold increase in removal rate and a twofold increase in Faraday efficiency. Additionally, the obtained NiOOH/Ti-Fe 2 O 3 electrode shows excellent ability (100% APAP removal in 2 h) and stability (removal efficiency greater than 94% after ten cycles) for pharmaceutical wastewater treatment containing APAP. These findings provide a novel and generalized strategy for enhancing the electrocatalytic ability of Ti-doped α -Fe 2 O 3 electrodes and offer valuable guidelines for exploring efficient and economic electrocatalysts for refractory wastewater treatment. [ABSTRACT FROM AUTHOR]