Prussian blue analogue nanospheres immobilized on self-floating biochar for micropollutant degradation via photo-Fenton process

Fe-Co Prussian blue analogue (PBA) nanospheres were immobilized on biochar (PBA-on-biochar) to remove contaminants via photo-Fenton process. The loading weight of FeCo PBA on biochar increased with increasing PBA aging temperature and time. The PBA exhibited efficient chloroquine phosphate (CQ) degradation under both LED light and sunlight, where OH and 1O2 dominated the oxidation. The CQ degradation was slightly affected by pH value (3.5–9.5) and co-existing anions like SO42−, Cl− and NO3–. The application potential of the PBA-on-biochar was evaluated in a continuous reaction device. Theoretical calculation revealed the dominant role of Fe sites in PBA for H2O2 activation. The degradation pathway was proposed based on nine intermediate products. Also, the excellent photo-Fenton activity and good floatability enable PBA-on-biochar to be efficient in inhibiting the activity of Microcystis aeruginosa under sunlight. The results implied that PBA-on-biochar is applicable for fast micropollutant oxidation from water.