Bridge Sites of Au Surfaces Are Active for Electrocatalytic CO Reduction.

Prior in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) studies of electrochemical CO reduction catalyzed by Au, one of the most selective and active electrocatalysts to produce CO from CO, suggest that the reaction proceeds solely on the top sites of the Au surface. This finding is worth updating with an improved spectroelectrochemical system where in situ IR measurements can be performed under real reaction conditions that yield high CO selectivity. Herein, we report the preparation of an Au-coated Si ATR crystal electrode with both high catalytic activity for CO reduction and strong surface enhancement of IR signals validated in the same spectroelectrochemical cell, which allows us to probe the adsorption and desorption behavior of bridge-bonded *CO species (*CO).

Accessing Organonitrogen Compounds via C-N Coupling in Electrocatalytic CO Reduction.

Given the limited product variety of electrocatalytic CO reduction reactions solely from CO and HO as the reactants, it is desirable to expand the product scope by introducing additional reactants that provide elemental diversity. The integration of inorganic heteroatom-containing reactants into electrocatalytic CO reduction could, in principle, enable the sustainable synthesis of valuable products, such as organonitrogen compounds, which have widespread applications but typically rely on NH derived from the energy-intensive and fossil-fuel-dependent Haber-Bosch process for their industrial-scale production. In this Perspective, research progress toward building C-N bonds in N-integrated electrocatalytic CO reduction is highlighted, and the electrosyntheses of urea, acetamides, and amines are examined from the standpoints of reactivity, catalyst structure, and, most fundamentally, mechanism.

Electrochemical Reductive N-Methylation with CO Enabled by a Molecular Catalyst.

The development of benign methylation reactions utilizing CO as a one-carbon building block would enable a more sustainable chemical industry. Electrochemical CO reduction has been extensively studied, but its application for reductive methylation reactions remains out of the scope of current electrocatalysis. Here, we report the first electrochemical reductive N-methylation reaction with CO and demonstrate its compatibility with amines, hydroxylamines, and hydrazine.

Interface Engineering of Silver-Based Heterostructures for CO Reduction Reaction.

The production of CO from the CO reduction reaction (CORR) is of great interest in the renewable energy storage and conversion, the neutral carbon emission, and carbon recycle utilization. Silver (Ag) is one of the catalytic metals that are active for electrochemical CO reduction into CO, but the catalysis requires a large overpotential to achieve higher selectivity. Constructing a metal-oxide interface could be an effective strategy to boost both activity and selectivity of the catalysis.

Bifunctional electrocatalysis for CO reduction via surface capping-dependent metal-oxide interactions.

Multi-component materials are a new trend in catalyst development for electrochemical CO2 reduction. Understanding and managing the chemical interactions within a complex catalyst structure may unlock new or improved reactivity, but is scientifically challenging. We report the first example of capping ligand-dependent metal-oxide interactions in Au/SnO2 structures for electrocatalytic CO2 reduction.

MOF-Derived Noble Metal Free Catalysts for Electrochemical Water Splitting.

Noble metal free electrocatalysts for water splitting are key to low-cost, sustainable hydrogen production. In this work, we demonstrate that metal-organic frameworks (MOFs) can be controllably converted into catalysts for the oxygen evolution reaction (OER) or the hydrogen evolution reaction (HER). The OER catalyst is composed of FeNi alloy nanoparticles encapsulated in N-doped carbon nanotubes, which is obtained by thermal decomposition of a trimetallic (Zn, Fe, and Ni) zeolitic imidazolate framework (ZIF).

Noble Metal-Free Oxygen Reduction Reaction Catalysts Derived from Prussian Blue Nanocrystals Dispersed in Polyaniline.

A highly efficient noble-metal-free catalyst for the oxygen reduction reaction (ORR) is derived from a composite of polyaniline (PANI) and Prussian blue analogue (PBA, Co3[Fe(CN)6]2) by pyrolysis. The composite consists of 2-5 nm PBA nanocrystals homogeneously dispersed in PANI. During the pyrolysis, the PBA nanocrystals serve as both the template for the pore formation and the precursor for the ORR active sites, which results in a nanoporous structure strongly coupled with the ORR active sites.