Internal Electric Field Enhancement by the I‐Rich Surface of Highly Crystallized BiOI Nanosheets for Boosted Photocatalytic Degradation of Phenol

Although the internal electric field (IEF) of bismuth oxyiodide (BiOI) is acknowledged as a potent driving force for efficient charge separation, enhancing intensity IEF remains challenge. Herein, highly crystalline BiOI nanosheets with I-rich surface are employed to intensify and direct migration. In comparison I-poor nanosheets, which possess Bi−O layer termination I-defects, demonstrates 62.5-fold improvement in its well-developed high structure, direction reversed by layers. This intensified induces numerous holes (h+) migrate primary exposed (001) facets electrons (e−) lateral efficiently, resulting separation spatially. Additionally, accumulates h+ superoxide radicals acts synergy enhance photodegradation phenol. The photocatalytic activity found be approximately fivefold threefold higher than that under full spectra visible light, respectively. manipulation through bulk structure regulation discussed, expecting rationally improve performances.