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Comprehensive Summary: A new electrochemical strategy for the atom transfer radical addition (ATRA) of polychloroalkanes across olefins has been realized by the synergism of paired electrolysis and halogen bonding activation. Notably, readily accessible 4,4‐di‐tert‐butyl bipyridine (dtbpy), acting as a halogen bonding acceptor, shifted the reduction potential of C—Cl bonds positively by 110 mV. The decreased operating potential leads to a wide substrate scope and excellent functional group compatibility. A diverse array of terminal and internal alkenes such as (hetero)aryl olefins, unactive aliphatic olefins, and natural products and drugs‐derived olefins were well compatible. [ABSTRACT FROM AUTHOR]

In this review, we highlighted the main achievements in the field of electrocatalytic generation of acyl radicals and their applications. These electrochemical strategies were introduced with an emphasis on the substrate scope, reaction limitation and underlying mechanism. The related reactions were categorized according to the pathways of acyl radical generation, including outer‐sphere electron transfer (ET), inner‐sphere ET, and hydrogen atom transfer (HAT) processes. [ABSTRACT FROM AUTHOR]

Work function strongly impacts the surficial charge distribution, especially for metal‐support electrocatalysts when a built‐in electric field (BEF) is constructed. Therefore, studying the correlation between work function and BEF is crucial for understanding the intrinsic reaction mechanism. Herein, we present a Pt@CoOx electrocatalyst with a large work function difference (ΔΦ) and strong BEF, which shows outstanding hydrogen evolution activity in a neutral medium with a 4.5‐fold mass activity higher than 20 % Pt/C. Both experimental and theoretical results confirm the interfacial charge redistribution induced by the strong BEF, thus subtly optimizing hydrogen and hydroxide adsorption energy. This work not only provides fresh insights into the neutral hydrogen evolution mechanism but also proposes new design principles toward efficient electrocatalysts for hydrogen production in a neutral medium. [ABSTRACT FROM AUTHOR]

The catalytic activity of metal clusters is closely related with the support; however, knowledge on the influence of the support on the catalytic activity is scarce. We demonstrate that Pt nanoclusters (NCs) anchored on porous TiO2 nanosheets with rich oxygen vacancies (VO‐rich Pt/TiO2) and deficient oxygen vacancies (VO‐deficient Pt/TiO2), display significantly different catalytic activity for the hydrogen evolution reaction (HER), in which VO‐rich Pt/TiO2 shows a mass activity of 45.28 A mgPt−1 at −0.1 V vs. RHE, which is 16.7 and 58.8 times higher than those of VO‐deficient Pt/TiO2 and commercial Pt/C, respectively. DFT calculations and in situ Raman spectra suggest that porous TiO2 with rich oxygen vacancies can simultaneously achieve reversed charge transfer (electrons transfer from TiO2 to Pt NCs) and enhanced hydrogen spillover from Pt NCs to the TiO2 support, which leads to electron‐rich Pt NCs being amenable to proton reduction of absorbed H*, as well as the acceleration of hydrogen desorption at Pt catalytic sites—both promoting the HER. Our work provides a new strategy for rational design of highly efficient HER catalysts. [ABSTRACT FROM AUTHOR]

Rational design of non-noble materials as highly efficient, economical, and durable bifunctional catalysts for oxygen evolution and reduction reactions (OER/ORR) is currently a critical obstacle for rechargeable metal-air batteries. A new route involving S was developed to achieve atomic dispersion of Fe-N x species on N and S co-decorated hierarchical carbon layers, resulting in single-atom bifunctional OER/ORR catalysts for the first time. The abundant atomically dispersed Fe-N x species are highly catalytically active, the hierarchical structure offers more opportunities for active sites, and the electrical conductivity is greatly improved. The obtained electrocatalyst exhibits higher limiting current density and a more positive half-wave potential for ORR, as well as a lower overpotential for OER under alkaline conditions. Moreover, a rechargeable Zn-air battery device comprising this hybrid catalyst shows superior performance compared to Pt/C catalyst. This work will open a new avenue to design advanced bifunctional catalysts for reversible energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

Co2N, Co3N, and Co4N are prepared by nitridation of the precursors β-Co(OH)2 (380 °C, 2 h), α-Co(OH)2 (380 °C, 2 h), and Co3O4, resp., under flowing NH3 (420 °, 2 h). [ABSTRACT FROM AUTHOR]