An Efficient Intercalation Supramolecular Structure for Photocatalytic CO₂ Reduction to Ethylene Under Visible Light

Abstract

Photocatalytic CO2 reduction (CO2PR) into multi‐carbon products (especially C2H4) is a highly attractive route for global carbon cycle, however, which is seriously limited by sluggish C‐C coupling kinetics and competitive hydrogen evolution reaction (HER) and so on. Herein, the fabrication of a novel supramolecular assembly of NiAl‐Fe‐TCPP is reported by intercalating iron porphyrin (Fe‐TCPP) into NiAl‐layered double hydroxide (NiAl‐LDH), and the resultant NiAl‐Fe‐TCPP exhibit superior catalytic performance on CO2PR to C2H4 under visible light irradiation in presence of photosensitizer. A high C2H4 selectivity up to 93.4% in the carbon‐containing products with the production rate as high as 24.7 µmol h−1 can be achieved over NiAl‐Fe‐TCPP. The ex/in situ X–ray absorption spectoscopy (XAS) indicates that the electron transfer between NiAl‐LDH and Fe‐TCPP can promote the generation of low‐valence of Fe sites, resulting in the efficient production of C2H4. The spin‐polarized density functional theory (DFT) calculations find that the synergistic mechanism that CO2 molecules are activated to CO on NiAl‐LDH and then spilled to Fe‐TCPP and coupled to COCHO#, which is further reduced to C2H4, are feasible in the perspective of Gibbs free energy. Moreover, the strong host‐guest interactions between NiAl‐LDH and Fe‐TCPP lead to the promoted photocatalytic activity and superior cycle stability.

Asymmetric Cu−N−La Species Enabling Atomic‐Level Donor‐Acceptor Structure and Favored Reaction Thermodynamics for Selective CO2 Photoreduction to CH4

“…Chemie depict that LaCu/CN displays the most quenched intensity and thus the lowest recombination of photogenerated carriers. [19] Furthermore, LaCu/CN also exhibits significantly enhanced photocurrent response compared with that of CN, La/CN, and Cu/CN, as displayed in the photocurrent-time curves (Figure 3e). In addition, electrochemical impedance spectroscopy measurements show the smallest interfacial resistance of LaCu/CN (Figure S14), suggesting its fastest interfacial charge transport.…”

Recent Developments in Nickel-Based Layered Double Hydroxides for Photo(-/)electrocatalytic Water Oxidation

“…The ion exchange method is particularly effective in the preparation of noncarbonate intercalated LDHs, as it allows for the incorporation of diverse organic (e.g., dodecylsulfate, metalloporphyrin, benzoate) and inorganic (e.g., CO 3 2– , NO 3 – , Br – , ClO 4 – , Cl – , SO 4 − ) anions into the Ni-based LDH interlayer. For example, Li et al employed this method to synthesize NiAl-LDH with intercalated Cl – and NO 3 – ions.…”

Isolated Cu Sites in CdS Hollow Nanocubes with Doping-Location-Dependent Performance for Photocatalytic CO2 Reduction

“…Doping engineering has enabled the construction of homogeneous and abundant atomic-level catalytic sites for photocatalytic CO 2 reduction with improved target product selectivity. , Cu species have been widely used as co-catalysts to improve the CO 2 reduction performance due to their special adsorption and activation ability to CO 2 . Notably, as for the aqueous photocatalytic CO 2 reduction system, proton reduction to H 2 presents a hardly avoidably competitive process. − Under such circumstances, it has been found that when Cu species are introduced to modify semiconductors, the photocatalytic CO 2 reduction performance is indeed enhanced and notably, the H 2 evolution rate is simultaneously promoted. , This is mainly ascribed to the fact that the photoelectrons with a prolonged lifetime induced by Cu doping indiscriminately reduce CO 2 molecules and protons. Such a situation limits the overall CO 2 reduction yield .…”