In Situ Self-Assembled ZIF-67/MIL-125-Derived Co₃O₄/TiO₂ p–n Heterojunctions for Enhanced Photocatalytic CO₂ Reduction

Abstract

Photocatalytic CO2 reduction to carbon fuels is regarded as an ideal and sustainable way to provide clean energy and solve environmental crisis. Herein, a p–n Co3O4/TiO2 heterojunction photocatalyst was synthesized by one-step pyrolysis of self-assembly ZIF-67/MIL-125, which was used in photocatalytic CO2 reduction for the first time. Co3O4 nanocages were highly dispersed on the surface of TiO2 nanoplates with an intimate contact. The optimal Co3O4/TiO2 exhibited a significantly enhanced CO evolution rate of 1256 μmol g–1 h–1 under simulated solar light, which was 2.4 times higher than that of pure Co3O4. The high photocatalytic performance of Co3O4/TiO2 was attributed to its enriched active sites and formed p–n heterojunctions. According to the electrocatalytic measurements, the possible mechanism and photoinduced charge transfer process were discussed in detail. We believe that this research provides a facile and efficient approach to fabricate MOF-derived heterojunction photocatalysts for CO2 reduction.

3D/2D Heterojunction Fabricated from RuS2 Nanospheres Encapsulated in Polymeric Carbon Nitride Nanosheets for Selective Photocatalytic CO2 Reduction to CO

“…The conversion of CO 2 into high value-added chemicals is one of the most desirable paths for carbon emission reduction because excessive CO 2 emission has destroyed the natural carbon cycle process and exacerbated global warming. − Photocatalytic reduction driven by renewable solar energy is considered as a promising CO 2 conversion technique to tackle energy depletion and environment deterioration problems, − which can effectively conquer the thermodynamic limitations of breaking CO bonds owing to the high dissociation energy (about 750 kJ/mol) . However, for most photocatalysts reported, the low conversion efficiency and poor selectivity remain the unsolved challenging issues in the photocatalytic reduction of CO 2 into CO, CH 3 OH, CH 4 , etc. − Therefore, exploiting a new efficient alternative or structure modification strategy is much desired for photocatalysts.…”

Removal of carbon dioxide using zeolitic imidazolate frameworks: Adsorption and conversion via catalysis

“…ZIF materials were also used as precursor for the synthesis of metal oxide embedded into carbon such as ZIF‐67/MIL‐125‐derived Co 3 O 4 /TiO 2 (Figure 17). [ 215,343 ]. Photocatalytic reduction of CO 2 leads to formation of methanol, [ 337 ] CO, [ 334 ] or CH 4 .…”

A Review on Removal of Carbon Dioxide (CO2) using Zeolitic Imidazolate Frameworks: Adsorption and Conversion via Catalysis

“…Schematic illustration of charge transfer over Co3O4/TiO2 under simulated solar light. [342] Ru-dye/ZIF-67 was reported for photocatalytic CO2 reduction under mild conditions [326] . The The catalyst can be recyclable with good stability [326] .…”