Nonprecious metal catalysts (NPMCs) FeNC are promising alternatives to noble metal Pt as the oxygen reduction reaction (ORR) catalysts for proton‐exchange‐membrane fuel cells. Herein, a new modulation strategy is reported to the active moiety FeN4 via a precise “single‐atom to single‐atom” grafting of a Pt atom onto the Fe center through a bridging oxygen molecule, creating a new active moiety of Pt1O2Fe1N4. The modulated FeNC exhibits remarkably improved ORR stabilities in acidic media. Moreover, it shows unexpectedly high catalytic activities toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), with overpotentials of 310 mV for OER in alkaline solution and 60 mV for HER in acidic media at a current density of 10 mA cm−2, outperforming the benchmark RuO2 and comparable with Pt/C(20%), respectively. The enhanced multifunctional electrocatalytic properties are associated with the newly constructed active moiety Pt1O2Fe1N4, which protects Fe sites from harmful species. Density functional theory calculations reveal the synergy in the new active moiety, which promotes the proton adsorption and reduction kinetics. In addition, the grafted Pt1O2 dangling bonds may boost the OER activity. This study paves a new way to improve and extend NPMCs electrocatalytic properties through a precisely single‐atom to single‐atom grafting strategy.

An efficient, sustainable organocatalyst, glycine betaine, was developed for the reductive functionalization of CO with amines and diphenylsilane. Methylamines and formamides were obtained in high yield by tuning the CO pressure and reaction temperature. Based on identification of the key intermediate, that is, the aminal, an alternative mechanism for methylation involving the C silyl acetal and aminal is proposed. Furthermore, reducing the CO amount afforded aminals with high yield and selectivity. Therefore, betaine catalysis affords products with a diversified energy content that is, formamides, aminals and methylamines, by hierarchical two-, four- and six-electron reduction, respectively, of CO coupled with C-N bond formation.

An effective and inexpensive organocatalyst tetrabutylammonium fluoride (TBAF) was developed for the reductive functionalization of CO with amines to selectively afford formamides or methylamines by employing hydrosilanes. Hydrosilanes with different substituents show discriminatory reducing activity. Thus, the formation of formamides and further reduction products, that is, methylamines could be controlled by elegantly tuning hydrosilane types. Formamides were obtained exclusively under an atmospheric pressure of CO with triethoxysilane. Using phenylsilane as a reductant, methylamines were attained with up to 99 % yield at 50 °C coupled to a complete deoxygenation of CO . The crucial intermediate silyl formate in the formylation step was identified and thereby a tentative mechanism involving the fluoride-promoted hydride transfer from the hydrosilane to CO /formamide was proposed. Striking features of this metal-free protocol are formylation and methylation of amines by reductive functionalization of CO with hydrosilanes and mild reaction conditions.

No abstract

Single‐Atom Catalysts Carbon‐supported single‐atom catalysts are subjected to surface oxidation and hydroxylation upon long‐term exposure to ambient environment, causing severe performance degradation. The hydrogen passivation strategy developed by Jianglan Shui and co‐workers in article number 2103600 can protect the catalytic active sites and ultimately improve the storage stability of single‐atom catalysts.