Bifunctional hydrogen production and storage on 0D–1D heterojunction of Cd0.5Zn0.5S@Halloysites

Abstract

Development of efficient solar‐driven hydrogen (H2) evolution and H2 storage materials is challenging. Sulfide nanocatalysts show large potential for H2 production, but suffer from the drawbacks of inefficient charge separation, serious photocorrosion, and easy agglomeration. Herein, a 0D–1D satellite‐core ethylenediaminetetraacetic acid (EDTA)‐bridged Cd0.5Zn0.5S@halloysite nanotubes tertiary structure is designed via facile in situ assembly, which settles all the above‐mentioned issues and achieves exceptional and stable photocatalytic H2 evolution and storage. Significantly, EDTA grafted on halloysites as the hole (h+) traps steers the photogenerated h+ and electrons (e−) from Cd0.5Zn0.5S separately to halloysites and outer surface Pt sites, achieving efficient directional separation between h+ and e− and inhibiting the h+‐dominated photocorrosion occurring on Cd0.5Zn0.5S. Benefiting from these advantages, the hierarchy shows an unprecedented photocatalytic H2 evolution rate of 25.67 mmol g−1 h−1 with a recording apparent quantum efficiency of 32.29% at λ = 420 nm, which is seven‐fold that of Cd0.5Zn0.5S. Meanwhile, an H2 adsorption capacity of 0.042% is achieved with the room temperature of 25 °C and pressure of 2.65 MPa. This work provides a new perspective into designing hierarchical structure for H2 evolution, and proposes an integration concept for H2 evolution and storage.