Fast and Long-Lasting Iron(III) Reduction by Boron Toward Green and Accelerated Fenton Chemistry

Generation of hydroxyl radicals in the Fenton system (Fe-II/H2O2) is seriously limited by the sluggish kinetics of Fe(III)reduction and fast Fe(III)precipitation. Here, boron crystals (C-Boron) remarkably accelerate the Fe-III/Fe(II)circulation in Fenton-like systems (C-Boron/Fe-III/H2O2) to produce a myriad of hydroxyl radicals with excellent efficiencies in oxidative degradation of various pollutants. The surface B-B bonds and interfacial suboxide boron in the surface B(12)icosahedra are the active sites to donate electrons to promote fast Fe(III)reduction to Fe(II)and further enhance hydroxyl radical production via Fenton chemistry. The C-Boron/Fe-III/H(2)O(2)system outperforms the benchmark Fenton (Fe-II/H2O2) and Fe-III-based sulfate radical systems. The reactivity and stability of crystalline boron is much higher than the popular molecular reducing agents, nanocarbons, and other metal/metal-free nanomaterials.