Tuning Gold Nanoparticles with Chelating Ligands for Highly Efficient Electrocatalytic CO₂ Reduction

Abstract

Capped chelating organic molecules are presented as a design principle for tuning heterogeneous nanoparticles for electrochemical catalysis. Gold nanoparticles (AuNPs) functionalized with a chelating tetradentate porphyrin ligand show a 110‐fold enhancement compared to the oleylamine‐coated AuNP in current density for electrochemical reduction of CO2 to CO in water at an overpotential of 340 mV with Faradaic efficiencies (FEs) of 93 %. These catalysts also show excellent stability without deactivation (<5 % productivity loss) within 72 hours of electrolysis. DFT calculation results further confirm the chelation effect in stabilizing molecule/NP interface and tailoring catalytic activity. This general approach is thus anticipated to be complementary to current NP catalyst design approaches.

Transition metal-based catalysts for the electrochemical CO2reduction: from atoms and molecules to nanostructured materials

“…In order to overcome this limitation, the surfactant molecules bound to Au NPs were replaced by chelating porphyrin-like tetradentate ligands with S-terminal anchoring groups. 422 The latter act as hollow scaffolds on Au NPs, interacting with the metal catalyst but without hindering the accessibility of the catalytic sites. This structural modification led to a 110-fold current enhancement in comparison with the parent oleylaminecoated Au NPs, efficiently producing CO (FE up to 93%) at an overpotential of 340 mV (Fig.…”

“…The electronic effect due to Au-S interactions was estimated to be negligible. 422 In an earlier study, the same authors used tetrapodal S-terminal porphyrin platforms to functionalize polycrystalline Cu electrodes for electrochemical CO reduction (CORR). 423 Based on DFT calculations, the different selectivity toward oxygenates production experimentally observed for various cage sizes was tentatively ascribed to a different stabilization of a key ketene intermediate via H-bonding interactions with the porphyrin cap.…”

Electroreduction of CO2 to CO Paired with 1,2-Propanediol Oxidation to Lactic Acid. Toward an Economically Feasible System

“…46% after 2 hours. Numerous studies have shown the different performance of Au nanoparticles [27][28][29][30] compared to Au plate electrodes highlighting the importance of the structure and geometry of the electrode surface. The performance of CO2 reduction can be improved by the use of different Au nanoparticles in terms of size, loading and/or by the use of oxide-derived Au electrodes.…”

Progress in development of electrocatalyst for CO2 conversion to selective CO production

“…Because of the intrinsic properties of each material, the selectivity of products from the CO 2 RR mainly depends on the initial catalyst materials. In this context, noble metals such as Au, Ag, and Pd have been the most rational choice for electrocatalysts in CO production. These noble metals have been extensively studied as representative model catalysts for CO production, to develop new strategies for high performance and to understand fundamental reaction mechanisms.…”