fig6
Figure 6. Possible mechanism of round-the-clock photocatalytic hydrogen production over the S-scheme SMSED/CdS heterojunction. (A) UV-visible-light-driven catalysis; (B) Dark catalysis. IEF: Internal electric field. Path 1: Electrons in SMSED transition from the ground state to an excited state, and then to the CB and enter traps; Path 2: Photoluminescence; Path 3: The path of photo-generated electrons in SMSED. SMSED: Sr2MgSi2O7:(Eu,Dy); CB: conduction band; VB: valence band; UV: ultraviolet; NHE: normal hydrogen electrode.
