Fe/Mo2C loaded on reed straw cellulose biochar as a Fenton-like catalyst for the degradation of acetaminophen over a wide pH range

The Fenton reaction is renowned for its high efficiency and well-established operational framework in medicinal chemistry, and environmental remediation. In this study, a novel pH-adaptive Fenton-like catalyst was developed by anchoring Fe-doped molybdenum carbide (Mo 2 C) nanoparticles onto reed straw cellulose biochar via a two-step calcination process, yielding a series of composites designated as Fe x @Mo 2 C/BC (x = 1, 2, 3). Among these, the Fe 1 @Mo 2 C/BC catalyst demonstrated exceptional performance in the presence of H 2 O 2 , achieving complete degradation (100 %) of 20 mg/L acetaminophen (ACE) within 30 min. Notably, the catalyst maintained high degradation efficiency across a wide pH range (pH 2–10), retaining 74.27 % activity after four reuse cycles, underscoring its robustness and adaptability. Mechanistic investigations revealed that Mo 2 C played a pivotal role in promoting the reduction of Fe 3+ to Fe 2+ , thereby sustaining the Fenton-like catalytic cycle. Simultaneously, the in situ generation of H + helped preserve an acidic microenvironment, effectively suppressing the precipitation of inactive Fe(OH) 3 species. The integration of biochar further enhanced the structural stability of the catalyst and significantly reduced iron ion leaching. The Quenching experiments identified superoxide radicals (O 2 •- ) as the primary reactive oxygen species responsible for ACE degradation. Additionally, the active sites and degradation pathways of ACE were elucidated through density functional theory (DFT) calculations and high-performance liquid chromatography-mass spectrometry (LC-MS) analysis. Overall, this work presents a compelling strategy for designing high-efficiency, pH-tolerant Fenton-like catalysts, offering both theoretical insights and practical solutions for wastewater treatment and the valorization of agricultural biomass.