Two-dimensional Ti3C2Tx anchored on three-dimensional SiC honeycomb framework for efficient and cyclic photocatalytic degradation of organic pollutants

Abstract

The excellent recyclability of SiC foam renders it an ideal catalyst in the field of photocatalytic degradation, however to further improve its photocatalytic efficiency remains a major challenge in current research. In this regard, a honeycomb-like porous SiC foam was successfully constructed through freeze-drying and polymer-to-ceramic derivation method, with two-dimensional Ti3C2Tx nanosheets anchored on its three-dimensional framework. Their photocatalytic performances were evaluated by the degradation of methylene blue (MB) under visible-light irradiation. All Ti3C2Tx/SiC hybrid foams show superior photocatalytic degradation capability compared with SiC foam, with a highest removal rate (adsorption and degradation) reaching 94.4% for TSF-4, denoting an increasement of 50.4%. Even after five cycles, the removal rate remained at 91.4% with only a slightly loss of 3%, suggesting its excellent recycling performance. These desirable results stem from the unique structural design, in which the porous structure facilitates the contact between catalyst and pollutant, while the Ti3C2Tx/SiC heterojunction promotes effective separation of photogenerated carriers. This work paves the way for the development of lightweight, efficient and easily recyclable photocatalyst for wastewater purification.