Facet Coupling Design for Bi4TaO8Cl/g‐C3N4 via Electrostatic Self‐Assembly to Enhance Photocatalytic Activity

Abstract Finely heterojunction and coupling facets design are essential to enhance photocatalytic activity. Herein, 2D/2D g‐C 3 N 4 −Bi 4 TaO 8 Cl catalysts were generated by ball‐milling‐assisted electrostatic self‐assembly strategy. The surface charge of Bi 4 TaO 8 Cl‐(001) facet can be fine altered from negative to positive by acidic solution treatment, resulting in that Bi 4 TaO 8 Cl nanoplates are parallelly coupled with g‐C 3 N 4 ‐(002) plane to form top‐top coupling facets. The facets coupling optimization, strong interfacial electric field and contact, and rapid charge transfer endow (002)g‐C 3 N 4 /(001) Bi 4 TaO 8 Cl catalysts with greatly enhanced photocatalytic activity of CO production and MO degradation relative to individual g‐C 3 N 4 , Bi 4 TaO 8 Cl and lateral‐top g‐C 3 N 4 −Bi 4 TaO 8 Cl catalyst. This present study provides inspiration to further design high‐performance heterojunction catalysts by adjusting surface charge with simple method.