Immobilized Molecular Catalysts for CO₂Photoreduction

Abstract

Catalytic carbon dioxide transformation to low valence carbon molecules such as carbon monoxide, formic acid, methanol and methane is a sustainable way to produce fuels and chemicals. Molecular catalysts can be designed to selectively transform CO2 at mild conditions, but a solvent medium is required. Instead, the molecular catalysts can be immobilized on solid supports to facilitate the continuous flow procedure and the separation of the products to recycle the catalytic systems for a more sustainable process. Photosensitive supports may also favor the light‐absorbing steps and electron transfer processes. In this article, the recent results obtained in the photocatalytic CO2‐reduction using catalytic systems formed by molecular compounds anchored on solids are reviewed.

Bioinspired and biomolecular catalysts for energy conversion and storage

“…Immobilizing a catalyst on an electrode is a promising approach to enhance electron transfer from the electrode to the catalyst and to facilitate analysis of electrochemical data. As noted above, immobilizing catalysts also can enhance catalyst robustness, as well as impact activity and selectivity [99][100][101][102]. This strategy has been productive for both biocatalysts and biomimetic catalysts, which may be adsorbed directly onto an electrode or incorporated into a polymer electrode coating.…”

Morphology Control of Supramolecular Assembly for Superior CO2Photoreduction

“…Light-driven utilization of CO 2 as a feedstock to synthesize value-added chemical fuels is promising from the perspective of sustainability. , Numerous catalysts including molecular metal complexes and inorganic and organic semiconductors have been developed to realize efficient CO 2 photoreduction. − In particular, molecular metal complexes play versatile roles in photocatalytic CO 2 reduction. They can be not only used as homogeneous photocatalysts but also integrated with various solid supporters to construct heterogeneous hybrid photocatalysts. ,− Moreover, transition metal complexes can be heterogenized by forming coordination polymers. − The durability, efficiency, and recyclability of photocatalysts can be improved after heterogenization of molecular catalysts. − Heterogenization is emerging as a powerful strategy to optimize photocatalytic performances of transition metal complexes in CO 2 photoreduction. , Heterogeneous photocatalysts consisting of transition metal complexes with different sizes ranging from nanometers to micrometers have been established. Knowing more about the impact of morphology on CO 2 photoreduction is beneficial to designing superior heterogeneous molecular catalysts.…”

Constructing N-Coordinated Co and Cu Single-Atomic-Pair Sites toward Boosted CO2 Photoreduction

“…Immoderate combustion of fossil fuel leads to the enrichment of greenhouse gas CO 2 in the atmosphere, which further causes a series of related environmental issues such as global warming and smoggy weather. , As a consequence, developing an effective strategy for CO 2 reduction is highly desirable for achieving the carbon-neutral cycle. , The visible-light-driven photoreduction of CO 2 into value-added chemicals has attracted tremendous interest as an ideal route to simultaneously relieve both CO 2 emission and energy crisis. − Among a variety of photocatalytic CO 2 reduction reaction products, carbon monoxide (CO) is a specially desirable product due to its broad industrial application in producing various chemical products including methanol and aliphatic aldehydes. , Although many active nanomaterials have been developed for the photocatalytic CO 2 conversion to CO, their catalytic efficiency is still unsatisfactory because of the intrinsic high thermodynamic stability of CO 2 molecule, large recombination rate of photoexcited electron–hole pairs, and limited fraction of active sites. , For the purpose of overcoming these issues, it is urgent to design and develop new robust photocatalysts to operate the CO 2 RR with excellent performance.…”

“…14,15 Although many active nanomaterials have been developed for the photocatalytic CO 2 conversion to CO, their catalytic efficiency is still unsatisfactory because of the intrinsic high thermodynamic stability of CO limited fraction of active sites. 16,17 For the purpose of overcoming these issues, it is urgent to design and develop new robust photocatalysts to operate the CO 2 RR with excellent performance.…”