Construction of UiO-66/Bi4O5Br2 Type-II Heterojunction to Boost Charge Transfer for Promoting Photocatalytic CO2 Reduction Performance

Abstract

One of the basic challenges of CO2 photoreduction is to develop efficient photocatalysts, and the construction of heterostructure photocatalysts with intimate interfaces is an effective strategy to enhance interfacial charge transfer for realizing high photocatalytic activity. Herein, a novel UiO-66/Bi4O5Br2 heterostructure photocatalyst was constructed by depositing UiO-66 nanoparticles with octahedral morphology over the Bi4O5Br2 nanoflowers assembled from the Bi4O5Br2 nanosheets via an electrostatic self-assembly method. A tight contact interface and a built-in electric field were formed between the UiO-66 and the Bi4O5Br2, which was conducive to the photo-electrons transfer from the Bi4O5Br2 to the UiO-66 and the formation of a type-II heterojunction with highly efficient charge separation. As a result, the UiO-66/Bi4O5Br2 exhibited improved photocatalytic CO2 reduction performance with a CO generation rate of 8.35 μmol h−1 g−1 without using any sacrificial agents or noble co-catalysts. This work illustrates an applicable tactic to develop potent photocatalysts for clean energy conversion.

Oxygen vacancy enhanced photocatalytic activity of Cu2O/TiO2 heterojunction

“…Compared to other heterojunctions reported in the literature, the TiO 2 /Cu 2 O-0.5 sample prepared in our work exhibits excellent catalytic activity ( Figure 3 E). 8 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 When the amounts of copper acetate are 1.5 mmol and 3 mmol, the yields of CO are 7.91 μmol g −1 h −1 and 5.7 μmol g −1 h −1 , respectively. The increase of Cu and the decrease of TiO 2 is not conducive to CO 2 conversion.…”

Encapsulating Ir nanoparticles into UiO-66 for photo-thermal catalytic CO2methanation under ambient pressure

“…The observation agrees well with the fact that the work function of Ir and the electron affinity of UiO-66 are 5.1 and 4.62 eV, respectively. 35,36 In the core-level Ir 4f spectrum of Ir nanoparticles (Fig. 2d), two peaks with binding energies of 63.89 and 60.87 eV correspond to the Ir 4f 5/2 and Ir 4f 7/2 orbitals of metallic Ir.…”

Recent progress on Bi4O5Br2-based photocatalysts for environmental remediation and energy conversion

“…Li et al synthesized UiO-66/Bi 4 O 5 Br 2 type II heterojunctions by encapsulating UiO-66 nanoparticles on Bi 4 O 5 Br 2 nanoflowers using an electrical self-assembly approach for CO 2 reduction. 76 UiO-66 with a high Fermi level transferred electrons to Bi 4 O 5 Br 2 with a bottom Fermi level until equilibrium, and the positive and negative charges generated during this process created an internal electric field, which drove the transfer of holes from UiO-66 to Bi 4 O 5 -Br 2 and electrons from Bi 4 O 5 Br 2 to UiO-66 (Fig. 10a).…”