Figure 9.

Schematic illustration of the proposed photocatalytic mechanistic pathway of charge separation and transfer in the 2% MoS₂/CeO₂ nanocomposite for solar light H₂ evolution. The energy band structure of p-MoS₂ and n-CeO₂ before coupling (a), the field direction of migration of electrons after made contact between p-MoS₂ and n-CeO₂ (b), the typical photoexcited charge transfer process at the thermodynamic equilibrium of the p–n heterojunction under visible light irradiation (c), and the internal electric field direction from n-type to p-type at the equilibrium (d).