0D-2D Z-Scheme photocatalyst Cd0.5Zn0.5S@Bi2Fe4O9 for effective hydrogen evolution from water

The fabrication of Z‑Scheme photocatalytic system is of great significance to promote the development of solar-hydrogen energy conversion. Herein, we constructed a promising direct Z‑Scheme photocatalyst 0D Cd0.5Zn0.5S QDs and 2D Bi2Fe4O9 nanosheets ([email protected]) via a facile method. By controlling the thickness of Bi2Fe4O9 nanosheets, not only the carrier migration distance was reduced, but also the built-in electric field of Bi2Fe4O9 can be enhanced, which both can increase the photocatalytic activity effectively. Furthermore, the close contact and strong electronic coupling between Bi2Fe4O9 and Cd0.5Zn0.5S as well as Z-scheme charge-carrier migration pathway were confirmed. As a result of the above advantages, the efficiency of carrier separation and migration of photocatalyst was improved, leading to the enhancement of photocatalytic hydrogen production activity. The optimized performance over [email protected] hybrids exhibits an enhanced H2 evolution rate of 811.5 μmol g−1h−1 (2.85 times higher than that of pristine Cd0.5Zn0.5S) under visible-light illumination (λ ≥ 420 nm) without any cocatalyst. This study may offer a promising strategy toward designing Cd0.5Zn0.5S-based Z-scheme photocatalysts for enhancing H2 evolution.