Circumventing CO₂ Reduction Scaling Relations Over the Heteronuclear Diatomic Catalytic Pair

Abstract

In the electrochemical CO 2 reduction reaction (CO 2 RR), CO 2 activation is always the first step, followed by the subsequent hydrogenation. The catalytic performance of CO 2 RR is intrinsically restricted by the competition between molecular CO 2 activation and CO 2 reduction product release. Here, we design a heteronuclear Fe 1 -Mo 1 dual-metal catalytic pair on ordered porous carbon that features a high catalytic performance for driving electrochemical CO 2 reduction to CO. Combining real-time nearambient pressure X-ray photoelectron spectroscopy, operando 57 Fe Mossbauer spectroscopy, and in situ attenuated total reflectance surface-enhanced infrared absorption spectroscopy measurements with density functional theory calculations, chemical adsorption of CO 2 is observed on the Fe 1 -Mo 1 catalytic pair through a bridge configuration, which prompts the bending of the CO 2 molecule for CO 2 activation and then facilitates the subsequent hydrogeneration reaction. More importantly, the dynamic adsorption configuration transition from the bridge configuration of CO 2 on Fe 1 -Mo 1 to the linear configuration of CO on the Fe 1 center results in breaking the scaling relationship in CO 2 RR, simultaneously promoting the CO 2 activation and the CO release.

Potential Alignment in Tandem Catalysts Enhances CO2-to-C2H4 Conversion Efficiencies

“…Unlike the hybrid structure, the *CO coverage at the surface of pristine Cu-R (Figure e) was observed only at very negative potentials, evidencing the benefit of incorporating Ni SAC in the catalyst. Notably, poor CO coverage was also observed when Cu-R was paired to either Ni Pc or Ag NPs (Figures f and S17), which could be attributed to the preferred *H delivery from the cocatalysts, competing with *CO for the adsorption site. − This hypothesis was confirmed by the lower Stark rate for Ni Pc + Cu-R (24 cm –1 /V) and Ag + Cu-R (21 cm –1 /V) in comparison with Ni SAC + Cu-R (40 cm –1 /V). These results reveal that wide-CO generation-potential-window Ni SAC can effectively provide *CO at the potential of the CO dimerization reaction for Cu-R, confirming our potential-matching tandem strategy.…”

Atomic Single-Layer Ir Clusters Enabling 100% Selective Chlorine Evolution Reaction

“…However, the water oxidation may occur at the same time producing unwanted byproducts. , Selective catalysis is crucial to the product purity. In most cases, there is in a trade-off between activity and selectivity of the bulk electrocatalysts due to the existence of scaling relationships in the adsorption energies of different adsorbates. − The activity enhancement toward the target product is often accompanied by the improvement of side reactions, making it difficult to obtain the exclusive selectivity. − Reducing the correlation degree of the scaling relationship or breaking the relationship are two effective approaches to improve the selectivity. − Another obstacle to selective catalysis is the complexity of the catalyst active sites. Bulk catalysts, like metal or metal oxide nanoparticles, usually have multiple types of adsorption sites on the surface, and it is difficult to have all active sites adsorb the target intermediates only, which provides opportunity for side reactions .…”

Mimicking Frustrated Lewis Pairs on Graphitic Carbon Nitride for CO2 Photoreduction

“…The modified metal as a Lewis acid site usually promotes the photocatalytic CO 2 reduction performance by enhancing the adsorption of CO 2 and/or reaction intermediates. However, too strong adsorption energy will inevitably lead to the difficulty of protonation or desorption in the following steps according to the scaling relationship. − Chen et al found that the introduction of rich-electron ferrocene into Zr-based metal–organic frameworks (MOFs) could weaken the Lewis acidity of metal Zr sites, thereby affecting CO 2 adsorption and CO desorption abilities and shifting the rate-determining step (RDS) . The photocatalytic CO yield of Zr–MOFs–Fc (2.0) with suitable Lewis acidity was up to 13 times that of unmodified MOFs.…”