Ordered porous carbon nitride embedded with truncated carbon nanotubes for boosting photocatalytic degradation

Limited light absorption and low charge separation rates are the main obstacles for graphitic carbon nitride- based photocatalysts. In terms of these defects, an ordered-porous graphitic carbon nitride composites (PCN@CNT) modified with truncated carbon nanotubes (CNTs) were composited through hydrothermalcalcination method in this work. Due to their electron trapping ability, the CNTs can enhance visible light absorption, narrow the bandgap, and act as electron concentrators, achieving that spatial separation of photo- generated carriers can inhibit electron-hole pair recombination efficiently. In addition, a controllable ordered- porous structure was constructed to provide abundant active sites and mass transfer channels, shortening the carrier migration path. These two modifications acted synergistically to enhance the catalysts' performance. The top-performing sample in this work, PCN@CNT-1, showed significant improvement in photovoltaic performance and achieved a 97.7 % degradation of rhodamine B, with a photocatalytic degradation rate constant (k k-value) more than three times that of PCN. This work demonstrates the potential for modification by coupling CNTs to design carbon-nitride-based photocatalysts with excellent catalytic performance, which can be used as catalysts for wastewater purification.