Giant Enhancement of Internal Electric Field Boosting Bulk Charge Separation for Photocatalysis

Incorporating carbon into Bi3O4Cl enhances its internal electric field by 126 times, which induces a bulk charge separation efficiency (ηbulk) of 80%. This ultrahigh ηbulk value presents a state‐of‐the‐art result in tuning the bulk charge separation. The generated C‐doped Bi3O4Cl has a noble‐metal‐ and electron‐scavenger‐free water‐oxidation ability under visible light, which is difficult to achieve with most existing photocatalysts.