Synthesis of an Environmentally Friendly Boron Nitride/Dye Composite Photocatalytic Material and Study on Degradation Mechanism of Tetracycline Wastewater

Abstract

AbstractHerein, a boron nitride‐dye composite photocatalytic material is synthesized by a simple and environmentally friendly method. In this method, boron nitride (BN) is added to Methylene blue (MB), Congo red (CR), Rhodamine B (RhB), methyl orange (MO) solution respectively, the formed composites (BN‐RhB, BN‐MB, BN‐MO and BN‐CR) can further work as photocatalyst to degrade tetracycline (TC) under visible light irradiation. The degradation rate of TC are 278.5, 303.3, 89 and 115.5 times by BN‐RhB, BN‐MB, BN‐MO and BN‐CR higher than that of BN. This is from the sensitization of dyes for BN and these dyes have different absorption ranges for visible light. After the adsorption of BN for RhB‐MO, RhB‐CR, MB‐MO and MB‐CR mixed solutions, BN‐RhB‐MO, BN‐RhB‐CR, BN‐MB‐MO and BN‐MB‐CR composites are formed. Compared with BN, their photodegradation rate for TC are improved by about 102.75, 118, 388 and 460.75 times, respectively. The photodegradation rate of BN‐MB‐CR (k=0.01843) is better than that of BN‐MB (k=0.01213), being from that binary dyes are more conducive to improve the electron transfer efficiency than single dyes. The involved photo‐active species during photodegradation process and the photodegradation intermediate products of TC have detected as well. The photodegradation rate (k=0.01213) of BN‐MB for TC is also higher than that of g‐C3N4 (k=0.00599), g‐C3N4‐MB (k=0.01027), TiO2 (k=0.01061) and TiO2‐MB (k=0.01163). This work is helpful to develop an environment‐friendly water treatment material.