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The alkaline oxygen evolution reaction (OER) is a promising avenue for producing clean fuels and storing intermittent energy. However, challenges such as excessive OH− consumption and strong adsorption of oxygen‐containing intermediates hinder the development of alkaline OER. In this study, we propose a cooperative strategy by leveraging both nano‐scale and atomically local electric fields for alkaline OER, demonstrated through the synthesis of Mn single atom doped CoP nanoneedles (Mn SA‐CoP NNs). Finite element method simulations and density functional theory calculations predict that the nano‐scale local electric field enriches OH− around the catalyst surface, while the atomically local electric field improves *O desorption. Experimental validation using in situ attenuated total reflection infrared and Raman spectroscopy confirms the effectiveness of the nano‐scale and atomically electric fields. Mn SA‐CoP NNs exhibit an ultra‐low overpotential of 189 mV at 10 mA cm−2 and stable operation over 100 hours at ~100 mA cm−2 during alkaline OER. This innovative strategy provides new insights for enhancing catalyst performance in energy conversion reactions. [ABSTRACT FROM AUTHOR]

The construction of allylic quaternary sp3‐carbon centers has long been a formidable challenge in transition‐metal‐catalyzed alkyl‐allyl coupling reactions due to the severe steric hindrance. Herein, we report an effective carbene strategy that employs well‐defined vinyl‐N‐triftosylhydrazones as a versatile allylating reagent to enable direct assembly of these medicinally desirable structural elements from low‐cost alkane feedstocks. The reaction exhibited excellent site selectivity for tertiary C−H bonds, broad scope (>60 examples and >20 : 1:0 r. r.) and good efficiency, even on a gram‐scale, making it a convenient alternative to the well‐known Trost–Tsuji allylation reaction for the formation of alkyl–allyl bonds. Combined experimental and computational studies were employed to unravel the mechanism and origin of site‐ and chemoselectivity of the reaction. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru)‐based catalysts, with considerable performance and desirable cost, are becoming highly interesting candidates to replace platinum (Pt) in the alkaline hydrogen evolution reaction (HER). The hydrogen binding at Ru sites (Ru−H) is an important factor limiting the HER activity. Herein, density functional theory (DFT) simulations show that the essence of Ru−H binding energy is the strong interaction between the 4dz2 orbital of Ru and the 1s orbital of H. The charge transfer between Ru sites and substrates (Co and Ni) causes the appropriate downward shift of the 4dz2 ‐band center of Ru, which results in a Gibbs free energy of 0.022 eV for H* in the RuCo system, much lower than the 0.133 eV in the pure Ru system. This theoretical prediction has been experimentally confirmed using RuCo alloy‐nanosheets (RuCo ANSs). They were prepared via a fast co‐precipitation method followed with a mild electrochemical reduction. Structure characterizations reveal that the Ru atoms are embedded into the Co substrate as isolated active sites with a planar symmetric and Z‐direction asymmetric coordination structure, obtaining an optimal 4dz2 modulated electronic structure. Hydrogen sensor and temperature program desorption (TPD) tests demonstrate the enhanced Ru−H interactions in RuCo ANSs compared to those in pure Ru nanoparticles. As a result, the RuCo ANSs reach an ultra‐low overpotential of 10 mV at 10 mA cm−2 and a Tafel slope of 20.6 mV dec−1 in 1 M KOH, outperforming that of the commercial Pt/C. This holistic work provides a new insight to promote alkaline HER by optimizing the metal‐H binding energy of active sites. [ABSTRACT FROM AUTHOR]

Single‐atom‐layer catalysts with fully activated basal‐atoms will provide a solution to the low loading‐density bottleneck of single‐atom catalysts. Herein, we activate the majority of the basal sites of monolayer MoS2, by doping Co ions to induce long‐range ferromagnetic order. This strategy, as revealed by in situ synchrotron radiation microscopic infrared spectroscopy and electrochemical measurements, could activate more than 50 % of the originally inert basal‐plane S atoms in the ferromagnetic monolayer for the hydrogen evolution reaction (HER). Consequently, on a single monolayer of ferromagnetic MoS2 measured by on‐chip micro‐cell, a current density of 10 mA cm−2 could be achieved at the overpotential of 137 mV, corresponding to a mass activity of 28, 571 Ag−1, which is two orders of magnitude higher than the multilayer counterpart. Its exchange current density of 75 μA cm−2 also surpasses most other MoS2‐based catalysts. Experimental results and theoretical calculations show the activation of basal plane S atoms arises from an increase of electronic density around the Fermi level, promoting the H adsorption ability of basal‐plane S atoms. [ABSTRACT FROM AUTHOR]