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Perfluorooctanoic acid degradation by a metal-free Fenton-like catalyst with dual-reaction-center confinement derived from biomass waste. • Biomass derived graphene is firstly used as metal-free Fenton catalyst. • The C F bonds in PFOA becomes weaker through interaction with OG. • The 3D macroscopic structure promotes H 2 O 2 decomposition. • The formation of the dual-reaction-center enhanced PFOA degradation. A three dimensional (3D) macroscopic modified graphene-based metal-free Fenton-like catalyst (OG) was obtained from biomass wastes in the aim of degrading perfluorooctanoic acid (PFOA). Results showed that the OG could degrade 93.4 % of PFOA in 150 min with a defluorination rate of 38.3 %. Experimental and theoretical studies verified that electron density migration occurred in OG via the C O C bridge, promoting electron loss from the C F bonds in PFOA with an obvious increase in the HOMO of F from 0.95 % to 15.46 %. Due to the confinement effect associated with the 3D graphene assembly, the barrier of OG (1.10 eV) was much smaller than that of the 2D graphene state (1.60 eV), resulting in an increase of in the C O bond length and in the activity of the C atom to promote H 2 O 2 decomposition. This study implies that 3D graphene derived from biomass waste could serve as a novel metal-free Fenton-like catalyst. [ABSTRACT FROM AUTHOR]

A perovskite LaCoO 3 functionalized Ti 4 O 7 reactive electrochemical membrane (REM) was developed for electro-enhanced peroxymonosulfate (PMS) activation (E-REM-PMS), addressing limitations in wastewater treatment efficiency, reusability, and interference resistance. It achieved 100% carbamazepine (CBZ) removal at a rate constant of 39.69 min−1, 233 and 23 times of electro-REM (E-REM) system without PMS and REM-PMS system without electricity. In-situ Fourier transform infrared spectroscopy (FTIR) highlighted the promotion of electro-activation on PMS, while density functional theory (DFT) calculations elucidated mechanism differences under three adsorption configurations. 1O 2 (2.97×10−9 M), SO 4 • − (2.09×10−11 M) and •OH (7.36×10−12 M) dominated the E-REM-PMS system, consistent with sequence of reactive species by DFT results. Continuous treatment of pharmaceutical wastewater confirmed 100% CBZ removal and 60%-70% TOC mineralization at ultrahigh water flux (642.86 L/m2·h) with minimal energy consumption (0.01 kWh/m3·order). This work proposed a high-performance and anti-fouling REM, offering an efficient and economical solution for wastewater treatment. [Display omitted] • LaCoO 3 /T 4 O 7 REM achieved ultrafast CBZ removal in 10.6 s (100 %, k = 39.69 min−1). • ROS quantification and DFT calculation revealed the main role of 1O 2 , SO 4 • − and •OH. • In-situ FTIR proved synergistic effect of LaCoO 3 /T 4 O 7 REM, electric field and PMS. • This work showed high water flux (636.62 L/m2·h) with minimal energy consumption. • Long-term test in pharmaceutical wastewater clarified its practical applicability. [ABSTRACT FROM AUTHOR]