Enhanced adsorption and photocatalytic activity of BiOI-MWCNT composites towards organic pollutants in aqueous solution

► BiOI-MWCNT composites were synthesised via EG-assisted solvothermal process. ► BiOI-MWCNT had a higher absorption and visible-light photocatalytic activity than BiOI. ► EIS profiles showed the effective interfacial charge-transfer between BiOI and MWCNT.