Switching charge transfer of C3N4/W18O49 from type-II to Z-scheme by interfacial band bending for highly efficient photocatalytic hydrogen evolution

The adsorption of triethylamine (TEOA) on C3N4 surface significantly uplifts its Femi level, inverses the continuous interfacial band bending to interrupted one, and thus switches the composite from type-II to Z-scheme, without the assistance of any electron shuttles. C3N4/W18O49 composites exhibit much better photocatalytic H2 activity compared with pure C3N4, and obtain H2 evolution rate of 8597 μmol h−1 g−1 (AQY of 39.1% at 420 nm) with Pt as cocatalyst and TEOA as hole scavenger.130