Epitaxial BiP5O14 layer on BiOI nanosheets enhancing the photocatalytic degradation of phenol via interfacial internal-electric-field

BiOI/BiP5O14 heterostructure with enhanced interfacial internal electric field for directional charge transfer and separation effectively were constructed successfully through epitaxial BiP5O14 layer on the surface of BiOI nanosheets. Dramatical enhanced internal electric field of BiOI/BiP5O14 heterostructure was established when BiP5O14 monolayer epitaxial grow on the surface of BiOI nanosheets by adding 2% of NaH2PO4. As a result, this heterostructure could boost the photodegradation and mineralization of phenol. Compared to pristine BiOI nanosheets, the photocatalytic reaction constant rates of phenol over the BiOI/BiP5O14 heterostructure were elevated over 8.5 times, and the corresponding mineralization ability was also enhanced 8.9 times due to the effective and directional charges transfer and separation. This work provides an evidential proof of rational designing heterostructure via epitaxial growth, and confirms the internal electric field drive charge transfer and separation directionally for promoted photocatalytic performances. [Display omitted] •Constructing epitaxial heterostructure of BiOI/BiP5O14 nanosheets was exploited clearly.•Significant enhanced internal electric field (IEF) of BiOI/BiP5O14 heterostructure was established by adding 2% of NaH2PO4.•Promoted IEF of BiOI/BiP5O14 heterostructure drive directional charge migration and separation effectively.•Photocatalytic activity and mineralization of phenol over the BiOI/BiP5O14 heterostructure were improved more than 8 times.