Novel Pt/COF Janus micromotor with bowl-like structure as an effective catalyst in extremely acidic environments

Abstract

To effectively enhance the catalytic activity and stability of the heterogeneous catalysts in extremely acidic environments, a novel Pt/COF Janus micromotor catalyst with bowl shape (BSJP) was prepared. The as-synthesized BSJP exhibited excellent catalytic degradation efficiency against methylene blue (MB) as the model substrate, owing to self-propelling motion caused by the unique bowl shape and the concentration effect of pollutants in the bowl-shaped structure. The catalyst has excellent catalytic efficiency. At circumneutral pH, the reaction rate constant of BSJP micromotor was 3.35 times of that of non-propellant particles. At pH = 2, Pt/COF-LZU1 BSJP exhibits the best activity with a maximum removal rate of 98.61 %. Moreover, even under extreme pH conditions (pH < 2), the catalytic degradation efficiency of MB remained high, and the structure and morphology of the catalyst remained unchanged. Importantly, the catalyst exhibited remarkable stability and recyclability. The degradation rate of MB and the removal rate of TOC remained above 90 % during the four cycles. This excellent catalytic performance under extremely acidic conditions was attributed to the physical confinement of Pt nanoparticles by stable COF-LZU1. This work confirms the broad application prospects of COF-carrier materials in water purification.