Copper embedded in nitrogen-doped carbon matrix derived from metal-organic frameworks for boosting peroxide production and electro-Fenton catalysis

Abstract

In this work, we demonstrated that metal-organic frameworks (MOFs) derived copper embedded in nitrogen-doped carbon composite (Cu/NC) could be applied as a high-efficient catalyst for simultaneously producing hydrogen peroxide (H2O2) and hydroxyl radical (·OH) via two-electron oxygen reduction reaction (ORR) and Fenton-like reaction, respectively. Based on the systematically physical characterization and electrochemical analysis, the copper species was encapsulated by the nitrogen-doped carbon layer to form a MOFs-derived Cu/NC catalyst, which presents superior two-electron ORR performance and long-term durability. In particular, the presence of nitrogen-doped carbon and the unique structure of the Cu/NC catalyst could provide active sites and accelerate the electron transfer during the ORR process. The boosting two-electron ORR properties of Cu/NC owning to the synergetic effect between dispersed copper and nitrogen groups. The oxidative degradation and electron paramagnetic resonance (EPR) spectra demonstrated that ·OH is the main reactive oxygen species (ROS) during the Bisphenol A (BPA) removal. The results presented herein suggest that MOFs-derived metal-carbon composite, as an all-in-one catalyst, can activate two-electron ORR for H2O2 production and Fenton-like for ·OH generation to achieve efficient pollutant degradation, rather than a single Cu-induced Fenton-like pathway.