Facile hetero-assembly of superparamagnetic Fe3O4/BiVO4 stacked on biochar for solar photo-degradation of methyl paraben and pesticide removal from soil

Abstract Herein we report synthesis of nano-hetero assembly of superparamagnetic Fe 3 O 4 and bismuth vanadate stacked on Pinus roxburghii derived biochar. Optical studies and band structure analysis indicate the hybridization between the two semiconductors facilitating photodegradation of pollutants in presence of natural sunlight. The nano-heterojunctions have been utilized for removal of emerging micro-pollutants as methylparaben (MeP). 97.4% of MeP degradation was achieved in presence of biochar/Fe 3 O 4 /BiVO 4 in 2 h. A degradation pathway has also been proposed on basis of mass spectrometry, chemical oxygen demand analysis and effects of various scavengers. Pinus derived biochar has also been utilized to see its long term effect on soil characteristics and fertility. The biochar has also been used to remove excessive pesticide from soil for lesser bioavailability.