A composite of biomass porous carbon supported g-C3N4 by 2,4,6-triaminopyrimidine modification for enhancing oxytetracycline removal

Since the traditional g-C3N4 photocatalyst was severely affected by low charge transfer rates and light absorption capacity, which inevitably limited its application in environmental pollution treatment. Herein, mixing the 2,4,6-triaminopyrimidine (TAP) doped melamine and biomass porous carbon (BPC), the TAP-BPC/CN composite with desirable conductivity was synthesized by one step thermal condensation. That is, the carbon atom of TAP was used to partially replace the nitrogen atom of tri-s-triazine structure of g-C3N4, and decreased the interlayer distance of graphite lamellar structure, then improved the electrical conductivity of the materials and suppressed the recombination of photogenerated carriers. At the same time, the incorporation of BPC also contributed to increase the active sites of the material and enhance the separation efficiency of photogenerated carriers. Furthermore, the formation of p-n homojunction in TAP-BPC/CN built the construction of an internal electric field at the interface, which induced the band bending and improved charge separation and transfer effectively. As a result, the sample of TAP-BPC/CN exhibited an excellent adsorption and photocatalytic activities in the degradation of oxytetracycline (OTC). This research provides a new strategy for efficient photocatalysts with high absorption and photocatalysis in the antibiotic wastewater treatment.