Z-scheme heterostructure of Cu2O/Pt/NH2-MIL-125(Ti) for photocatalytic CO2 reduction

Synergistic Enhancement of Photocatalytic H2 Evolution over NH2-MIL-125 Modified with Dual Cocatalyst

“…To verify the charge transfer performances of NH 2 -MIL-125, Pt/NH 2 -MIL-125, and CDs-Pt/NH 2 -MIL-125, the related photoelectrochemical characterization including photocurrent and electrochemical impedance spectroscopy (EIS) were measured as shown in Figure a,b. The pure NH 2 -MIL-125 exhibits a lower photocurrent density caused by higher charge carriers recombination . The photocurrent density of Pt/NH 2 -MIL-125 improved when compared to NH 2 -MIL-125, suggesting that the metal/semiconductor system formed by Pt on the surface of NH 2 -MIL-125, that is, cocatalyst, can provide active sites and promote the charge transfer.…”

“…The pure NH 2 -MIL-125 exhibits a lower photocurrent density caused by higher charge carriers recombination. 65 The photocurrent density of Pt/ NH 2 -MIL-125 improved when compared to NH 2 -MIL-125, suggesting that the metal/semiconductor system formed by Pt on the surface of NH 2 -MIL-125, that is, cocatalyst, can provide active sites and promote the charge transfer. CDs-Pt/NH 2 -MIL-125 shows the strongest photocurrent density, reflecting that CDs as an electronic mediator can greatly promote the absorption of visible light, enhance the generation of charges, and effectively inhibit the recombination of charge carriers.…”

“…The absorption peak at 1382 cm −1 corresponds to the stretching vibration of C−O− C. 58,64 There is an obvious characteristic peak of the Pt/NH 2 -MIL-125 and CDs-Pt/NH 2 -MIL-125 at 3439 cm −1 , which corresponds to the stretching vibration of −NH 2 . 65 The peak at 771 cm −1 is attributed to the telescopic vibration of Ti−O− Ti 65 in NH 2 -MIL-125(Ti). The peaks at 1623 and 1256 cm −1 correspond to the bending vibration of N−H and the tensile vibration of N−C, respectively.…”

Metal–organic frameworks in photocatalytic Z-scheme heterojunctions: an emerging technology

“…Additionally, the Schottky barrier formed between the Pt nanoparticles and the MOF prevented the complexation of the photogenerated carriers and improved their lifetime. 56 Striving towards metal-free photocatalysts, there have been research studies where instead of using metal-based electron mediators, carbonaceous mediators like reduced graphene oxide (r-GO) and g-C 3 N 4 have been successfully integrated in Z-schemes. Aiming towards the same, photocatalysts such as O-defective ZnO/r-GO/NH 2 -UIO-66 and g-C 3 N 4 /NH 2 -MIL 125 (Ti)/r-GO have been developed.…”

“…Additionally, the Schottky barrier formed between the Pt nanoparticles and the MOF prevented the complexation of the photogenerated carriers and improved their lifetime. 56…”