Ultrafast and energy-saving microwave-assisted conversion of inert carbon nanomaterials to highly efficient Fenton-like metal-free catalysts for pollutants degradation

Carbon-driven persulfate (PDS)-based Fenton-like reactions have been widely viewed as prospective strategies to cope with the water pollution. However, high cost, harsh condition and complex modification processes are usually required to boost the catalytic activities of carbocatalysts. Herein, we proposed an ultrafast, energy-efficient, and convenient approach to convert various low-performance carbon materials into highly efficient catalysts by microwave treatment in just 1 min without any other tedious treatment. This process only requires 57 kJ/g energy input, 5 orders of magnitude lower than the traditional calcination process. The catalytic performance of microwave-treated materials could increase by more than 380 times, which is even better than those of the single-atom catalysts. Moreover, DFT calculations and QSARs analyses reveal that the negatively charged carboxyl group is not conducive to the adsorption of PDS (S2O82−) due to electrostatic repulsion, and also increases the work function of the carbocatalysts, which hinders the electron transfer process. [Display omitted] •Superior Fenton-like catalysts can be obtained by microwave treatment in just 1 min.•This strategy requires 57 kJ/g energy input, much lower than traditional processes.•This strategy is promising for the large-scale production of efficient carbocatalysts.•The carboxyl group contents can be finely tuned with constant total oxygen contents.•The intrinsic reasons behind inhibitory effect of carboxyl groups have been revealed.