Engineering a highly dispersed core@shell structure for efficient photocatalysis: A case study of ternary novel BiOI@MIL-88A(Fe)@g-C 3 N 4 nanocomposite

•Novel ternary BiOI@MIL-88A(Fe)@g-C3N4 core@shell photocatalyst is reported.•Photocatalytic degradation mechanism of organic pollutants is investigated.•It is divulged that the photodegradation is increased by BiOI supporting.•Core@shell structure of MIL-88A(Fe)@g-C3N4 causes high activity.•Strong visible light absorption and electron transfer improve activity.