Transplanting Gold Active Sites into Non-Precious-Metal Nanoclusters for Efficient CO₂-to-CO Electroreduction

Abstract

Electrocatalytic CO 2 reduction reaction (CO 2 RR) is greatly facilitated by Au surfaces. However, large fractions of underlying Au atoms are generally unused during the catalytic reaction, which limits mass activity. Herein, we report a strategy for preparing efficient electrocatalysts with high mass activities by the atomic-level transplantation of Au active sites into a Ni 4 nanocluster (NC). While the Ni 4 NC exclusively produces H 2 , the Au-transplanted NC selectively produces CO over H 2 . The origin of the contrasting selectivity observed for this NC is investigated by combining operando and theoretical studies, which reveal that while the Ni sites are almost completely blocked by the CO intermediate in both NCs, the Au sites act as active sites for CO 2 -to-CO electroreduction. The Au-transplanted NC exhibits a remarkable turnover frequency and mass activity for CO production (206 mol CO /mol NC /s and 25,228 A/g Au , respectively, at an overpotential of 0.32 V) and high durability toward the CO 2 RR over 25 h.

Catalysis Synergism by Atomically Precise Bimetallic Nanoclusters Doped with Heteroatoms

“…This study provided evidence for the surface Cd–S–Au synergistic effect involved in CO 2 RR. Au 24 Cd 1 (SR) 18 (Figure c and d) and Au 47 Cd 2 (SR) 31 were successively reported to significantly enhance CO 2 conversion toward CO. , The surface heteroatom doping strategy can be extended to other heteroatom doped clusters such as Au 4 Ni 2 (SR) 8 (Figure e and f). , …”

“…The determined structural information on nanocluster catalysts imparts advantages in identifying active sites and exploring catalytic mechanisms, which can in turn guide the design and synthesis of high-performance catalysts. More notably, doping foreign metal atoms (i.e., heteroatoms) into a designated nanocluster is an effective strategy for tailoring its catalytic property through modulating the electronic properties, improving the structural robustness, and providing additional active sites for the absorption and activation of reactant molecules. − ,− Given structural characteristic of nanoclusters, the heteroatoms can be introduced into the surface of the parent homometal nanocluster, , in which they can directly act as active sites for improving the catalytic reactivity or cooperatively communicating with organic ligands to form surface multisites to promote the reactions occurring at different sites. The heterometallic atom can also replace the subsurface or kernel atom of the parent nanocluster, in which it can tune the electronic property through the electron transfer of subsurface/kernel heteroatoms to exterior metal atoms or vice versa, thereby imparting a substantial influence on the observed catalytic performance. ,,,, These researches bring about a new conceptual framework for understanding subnanometer-scale catalysis.…”

“…(e) Atomic structures of Ni 4 (SR) 8 and Au 4 Ni 2 (SR) 8 and (f) catalytic performances for CO 2 RR. Reproduced with permission from ref . Copyright 2022 American Chemical Society.…”

“…Li and co-workers reported a Au 19 Cd 2 (SR) 16 cluster that was prepared by substituting the surface Au atoms of 5c and d) and Au 47 Cd 2 (SR) 31 were successively reported to significantly enhance CO 2 conversion toward CO. 21,37 The surface heteroatom doping strategy can be extended to other heteroatom doped clusters such as Au 4 Ni 2 (SR) 8 (Figure 5e and f). 40,50 Recently, Li and co-workers made an extra effort to identify the active Cu 3 S 3 surface motif of the Cu 12 Ag 17 (SR) 12 (PPh 3 ) 4 cluster for the CO 2 formylation reaction with amines and found that Cu 12 Ag 17 (SR) 12 (PPh 3 ) 4 can integrate the advantages of homogeneous and heterogeneous catalysts, thereby exhibiting highly catalytic activity and recyclability. 2 As shown in Figure 6a, a series of the structurally comparable cluster catalysts including ■ CATALYTIC PERFORMANCES REMOTELY…”

Recent advances in atomically precise metal nanoclusters for electrocatalytic applications

“…Recently, Seong et al developed a remarkable strategy to prepare Au 2 Ni 3 and Au 4 Ni 2 by doping Au atoms into Ni 4 NCs, which made a radical change in catalyst selectivity from the HER to the CO 2 RR. 50 The synthesis route and the crystal structure of Au 2 Ni 3 and Au 4 Ni 2 are shown in Fig. 12A and B, as well as a clarification of the substitution of one nickel atom with two gold atoms.…”