Direct Z-scheme Heterojunction CeO2@NiAl-LDHs for Photodegradation of Rhodamine B and Photocatalytic Hydrogen Evolution: Performance and Mechanism

Herein, a direct Z-scheme heterojunction CeO2@NiAl-LDHs (LDHs=layered double hydroxides) with core-shell structure was constructed. It shows high oxidative degradation of rhodamine B (36.91 mg.g(-1).h(-1)) and hydrogen production by photoreduction (14.08 mmol.g(-1).h(-1)). Density functional theory (DFT) calculation shows that there was a built-in electric field in the heterojunction, which promotes the electron transfer from LDHs to CeO2. Surface photovoltage spectroscopy (SPV) and transient photovoltage spectra (TPV) confirmed that the presence of heterojunction accelerated the number of electron transfer, and the recombination of electron and hole was obviously inhibited, so as to participate in oxidation and reduction more. Thus, it makes CeO2@NiAl-LDHs heterojunction photocatalyst have high photocatalytic activity for photodegr , adation of rhodamine B and hydrogen production from water.