Assembly of 2D/2D Bi2WO6/Boron-doped g-C3N4 Z-type heterojunction photocatalysts for efficient antibiotic adsorption and degradation

The photocatalytic heterojunction systems have shown remarkable development in improving the efficiency of visible-light absorption and photocarriers separation. Herein, we successfully engineered efficient 2D/2D Bi2WO6/Boron-doped g-C3N4 (BiWO/BCN) architectures as Z-type heterojunction photocatalysts with different BiWO to BCN ratios for degradation of antimicrobial drug sulfamethoxazole (SMX) under visible illumination. The SMX degradation using the optimized 40%BWO/BCN sample was obviously enhanced, and the degradation rate was 99.3 % after 120 min of irradiation. Its degradation efficiency was 6.5-, 3.2-, and 2.9-times better than that of BiWO, CN, BCN, and, respectively. The significantly boosted performance of the BiWO/BCN photocatalyst was credited to the effective separation of photo-excited electron and hole pairs. The SMX photodegradation pathways have been explained with a complete assessment of the active species, which showed the major role of •O2− and electrons. The reusability tests proved the high photostability of 40%BiWO/BCN sample throughout 5 sequential cycles (only 3.8 % reduction was witnessed). Therefore, this work presents an innovative photocatalyst combination for green degradation of SMX antibiotic.