Directional crystal facets deposition constructed BiVO4/Ag/MnO2 with plasmon resonance for enhanced photocatalytic degradation of antibiotics in water

Degradation of ciprofloxacin (CIP) and tetracycline (TC) in water through photocatalysis is an attractive route. Utilizing the anisotropy of crystal to construct an interplanar electric field is an effective method to separate the catalyst carrier. Herein, we report a modification strategy based on decahedral bismuth vanadate (BiVO4, BVO) crystal facets regulation. Employing photo-deposition method, Ag and MnO2 nanoparticles were assembled on {0 1 0} and {1 1 0} crystal facets of BVO, separately. The conversion efficiency of solar energy to chemical energy was evaluated through the CIP and TC degradation experiment (at the initial concentration of 10 mg/L) and it reached a removal efficiency of 93.6% and 93.4% in 100 min using BAM-1.5, respectively, which were 4.23 times and 3.81 times faster than BVO. Mechanism study using free radical trapping experiment and electron paramagnetic resonance (EPR) tested the main active free radicals were ascribed as ·O2- and ·OH. The enhanced catalytic performance can be attributed to the synergistic effect of local surface plasmon resonance and Z-scheme heterojunction of Ag/MnO2 on the BVO. This work provides an intriguing and feasible solution for the preparation of advanced photocatalyst and pave the way for new catalyst finding.