Spherical covalent organic frameworks supported black phosphorus@Au nanocatalysts for nitrophenol hydrogenation in a high efficiently flow-through process

Exfoliated black phosphorus (BP) nanosheets possessing unique electron-reservoir and electron-donor properties could fast electron transfer, promising as a cocatalyst for catalysis. However, the catalytic process was limited by the morphology of BP nanosheets because the continuous pressure deriving from the effluent would dense the channel of stacked BP nanosheets. In this work, spherical covalent organic frameworks were synthesized and used as a platform to support BP nanosheets/Au nanocatalysts. The prepared heterostructure was applied to catalytic reduction of 4-nitrophenol under a flow-through catalytic process. An optimized permeation flux of 2500 L/m- 2(- |-)h-1 (LMH) and a reduction efficiency of 99 % was achieved. Furthermore, only 0.064 wt% of Au NPs was released after testing for 24 h. Our straightforward strategy to solve the issues suffering from the continuous treatment of effluent would facilitate the application of novel nanomaterials in environmental remediation.

Automated summary

In this study, a heterostructure of BP nanosheets/Au nanocatalysts supported by spherical covalent organic frameworks was successfully synthesized. The structure showed excellent performance in a flow-through catalytic reduction reaction and solved the issues encountered during continuous treatment of effluent.