Review on augmentation in photocatalytic activity of CoFe2O4 via heterojunction formation for photocatalysis of organic pollutants in water

In previous years, cobalt ferrite has gained huge consideration in the field of semiconductor photocatalysis for waste water treatment. Cobalt ferrite and its derivatives own tunable magnetic properties which results in higher absorption capability in comparison with other photocatalyst semiconductors. In the current review, a brief overview of CoFe2O4 as a semiconductor photocatalyst is presented and ferromagnetic behaviour of CoFe2O4 is also discussed. Few drawbacks such as agglomeration, photocorrosion and recombination rate of electrons-holes are also discussed. For the enhancement of photocatalytic action of cobalt ferrite, the role of cobalt ferrite with type I, type II, direct Z-scheme, solid state Z-scheme heterojunctions, Schottky and p-n heterojunctions based on different heterostructures were also discussed. In conclusive outlook formation of cobalt ferrite based heterojunctions is best approach for the enhancement of photocatalytic performance. This is because heterojunction formation enhanced the rate of charge separation and thus reduced the electron–hole recombination. Herein, this review highlights the CoFe2O4 based heterojunctions for the photodegradation of noxious organic pollutants in water. Furthermore, the future expectations and challenges in exploiting CoFe2O4 nanocomposites for water treatment, also discussed in precise conclusion of this review. Keywords: Spinel ferrites, CoFe2O4, Heterogeneous photocatalysis, Heterojunction formation, Visible light, Wastewater treatment