Enhancing visible-light-based photodegradation of antibiotics over facile constructed BiVO4/S-doped g-C3N4 heterojunctions in an airlift photocatalytic reactor

The development of new and effective photocatalytic heterojunctions for green environmental remediation under visible-illumination has received great attention in recent years. Herein, we assembled BiVO 4 -decorated S-doped g-C 3 N 4 (BVO/SCN) heterojunctions with different BVO:SCN ratios (5 to 30 wt% BVO) to achieve effective photocatalytic heterojunctions for visible-light-prompted degradation of antibiotic TC in a three-phase split-plate airlift photocatalytic reactor, in which successfully reducing charge recombination rate. Obviously, BVO/SCN endorsed greater photodecomposition performance of TC under visible-light (decompose 95.7 % of TC in 60 min), which compared to SCN was approximately 5-times enhancement. The TC mineralization efficiency of BVO/SCN hybrid (84 % within only 60 min) was higher than that of the individual BVO and SCN. The efficient internal self-mixing generated in the airlift photocatalytic reactor greatly contributed to increasing the TC degradation efficiency by improving the mass transfer and the irradiation process of the mixture, in which the degradation efficiency increased from 88 % without airlift to 95.7 % in airlift reactor. On the other hand, the high degradation efficiency was credited to the extended absorbing of visible-light and great separation of photo-prompted carriers through the formation of Z-type heterojunction between BVO and SCN. As recorded by the trapping investigates, the • O 2 − and • OH radicals act as the main reactive-species in the TC photocatalytic degradation process. Moreover, High durability of the developed BVO/BCN heterojunctions was obtained, in which 89.4 % TC degradation was still recorded after five rounds.