Dual-functional Mo<inf>2</inf>C quantum dots enriched N-doped graphitic carbon layers in advanced oxidation processes (AOPs)

Abstract

Advanced oxidation processes (AOPs) are reckoned effective for removing persistent and recalcitrant pollutants by reactive oxygen species (ROSs), including hydroxyl radicals (•OH), sulfate radicals (SO4•-), and superoxide radicals (•O2-), as well as singlet oxygen (1O2). In this work, the Mo2C quantum dots enriched N-doped graphitic carbon layers (Mo2C QDs/NGCLs) were constructed via a facile two-step methodology. Interestingly, the Mo2C QDs/NGCLs acted as a highly efficient cocatalyst and/or catalyst simultaneously in AOPs, in particular visible-light-driven (VLD) Fenton and VLD PMS activation. In the hydroxyl radical-based AOPs (•OH-AOPs), it exhibited a remarkable removal efficiency for a range of aromatic organic pollutants, including rhodamine B (RhB) (99.9 %), phenol (90 %), benzophenone-3 (BZP) (83 %), methyl orange (MO) (58 %), methyl blue (MB) (89 %), ibuprofen (IBU) (100 %), and carbamazepine (CBZ) (50 %). Sulfate radicals-based AOPs (SR-AOPs) effectively degrade RhB (72 %), MO (83 %), IBU (70 %), and BZP (100 %). Thus, the present findings confirmed the potential of transition metal carbides for AOP applications and established a solid theoretical and technical basis for further research.