Construction of Fe9S10@Fe2O3@Fe3S4 conductor-semiconductor type heterojunction as photoactivator of peroxymonosulfate toward the degradation of Malachite Green

Abstract An efficient Fe9S10@Fe2O3@Fe3S4 conductor-semiconductor type heterojunction was synthesized by hydrothermal route. The obtained composite exhibits a snowflakes-like structure, and displays excellent photocatalytic activity for Malachite Green (MG), which reached 98.94% by peroxymonosulfate (PMS) activation under 80 min visible light irradiation. This enhanced photocatalytic performance is mainly attributed to the strong internal electric field (E-field) constructed at hetero-interface, accelerating charge carriers transport. Meanwhile, the external addition of electron acceptor, PMS, could greatly promote the separation of charge carriers. In general, this work may provide a route to design efficient photocatalysts for practical application in the field of water purification.