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Li+/Na+ exchange has been extensively explored as an effective method to prepare high‐performance Mn‐based layered cathodes for Li‐ion batteries, since the first report in 1996 by P. G. Bruce (Nature, 1996. 381, 499–500). Understanding the detailed structural changes during the ion‐exchange process is crucial to implement the synthetic control of high‐performance layered Mn‐based cathodes, but less studied. Herein, in situ synchrotron X‐ray diffraction, density functional theory calculations, and electrochemical tests are combined to conduct the systemic studies into the structural changes during the ion‐exchange process of an Mn‐only layered cathode O3‐type Li0.67[Li0.22Mn0.78]O2 (LLMO) from the corresponding counterpart P3‐type Na0.67[Li0.22Mn0.78]O2 (NLMO). The temperature‐resolved observations combined with theoretical calculations reveal that the Li+/Na+ exchange is favorable thermodynamically and composited with two tandem topotactic phase transitions: 1) from NLMO to a layered intermediate through ≈60% of Li+/Na+ exchange. 2) then to the final layered product LLMO through further Li insertion. Moreover, the intermediate‐dominate composite is obtained by slowing down the exchange kinetics below room temperature, showing better electrochemical performance than LLMO obtained by the traditional molten‐salt method. The findings provide guides for the synthetic control of high‐performance Mn‐based cathodes under mild conditions. [ABSTRACT FROM AUTHOR]

(Deuterium‐labeled) CF2H‐ and CFH2‐moieties are of high interest in drug discovery. The high demand for the incorporation of these fluoroalkyl moieties into molecular structures has witnessed significant synthetic progress, particularly in the (deutero)hydrodefluorination of CF3‐containing compounds. However, the controllable replacement of fluorine atoms while maintaining high chemoselectivity remains challenging. Herein, we describe the development of a selective (deutero)hydrodefluorination reaction via electrolysis. The reaction exhibits a remarkable chemoselectivity control, which is enabled by the addition of different organoboron sources. The procedure is operationally simple and scalable, and provides access in one step to high‐value building blocks for application in medicinal chemistry. Furthermore, density functional theory (DFT) calculations have been carried out to investigate the reaction mechanism and to rationalize the chemoselectivity observed. [ABSTRACT FROM AUTHOR]

Co-substituted Cu-Mn spinel oxides were synthesized, characterized, and catalytic performance for benzene oxidation was evaluated. Spinel phases, and the substitution of Mn sites by Co were confirmed for the ternary oxides. Co 0.2 Cu 0.8 MnO y showed the highest activities with the lowest apparent activation energy among the ternary oxides. The improved catalytic properties due to Co substitution are attributed to more activated lattice oxygen, stronger adsorption of benzene, and a larger specific surface area. Density functional theory simulations also revealed that the Co substitution enhanced the reactivity of the lattice oxygen. Adsorbed and activated benzene reacted with lattice oxygen to form abundant oxygen defects, which promoted O 2 adsorption and dissociation, contributing to enhanced catalytic activity. The effect of water vapor on the catalytic benzene oxidation was also clarified. [Display omitted] • Co substitution to Cu-Mn spinel oxide improved the benzene decomposition efficiency. • Experimental and DFT data confirmed the strongly enhanced lattice oxygen activity. • Adsorbed benzene reacted with lattice oxygen creating abundant oxygen vacancies. • Co promoted O 2 adsorption, dissociation, and oxygen replenishment into vacancies. • Water vapor showed a limited inhibition effect on benzene oxidation. [ABSTRACT FROM AUTHOR]

Selective hydrogenation of aromatic ring represents an essential process for the valorization of lignin in the chemical industry but achieving this process at low temperature is still a challenge. Herein, a series of Ru-based catalysts were investigated. It is found that Ru/γ-Al 2 O 3 with small Ru metal particle size shows the low activity in this system. A unique and strong metal-support interaction for Ru/γ-Al 2 O 3 indicates that the strongly bounded Ru-O-Al sites lead to the positive charge of Ru species. In contrast, Ru/α-Al 2 O 3 with well-dispersed Ru nanoparticles supported on α-Al 2 O 3 can successfully catalyze the selective hydrogenation of lignin-derived aromatic compounds at room temperature. Ru/α-Al 2 O 3 has the excellent recyclability, air stability and the highest activity. The selective hydrogenation of aromatic ring for Ru/α-Al 2 O 3 results from the fast dissociation of H 2 and the high adsorption energy of aromatic ring as revealed by X-ray absorption spectra, X-ray photoelectron spectroscopy and density functional theory calculations. [Display omitted] • Aromatic ring hydrogenation was achieved at room temperature over Ru/α-Al 2 O 3. • H 2 rather than solvents provided the only hydrogen source in this reaction. • The fast H 2 dissociation and high DPE adsorption energy occurred on Ru/α-Al 2 O 3. • More metal Ru exists in Ru/α-Al 2 O 3 and positively charged Ru exists in Ru/γ-Al 2 O 3. • The reaction route of the aromatic ring hydrogenation for DPE was presented. [ABSTRACT FROM AUTHOR]

[Display omitted] • Selective hydrogenation of arenes is achieved at room temperature over Rh/α-Al 2 O 3. • Rh-1/α-Al 2 O 3 exhibits the highest performance for the conversion of DPE and toluene. • The metal Rh nanoparticles are distributed on α-Al 2 O 3 for Rh-1/α-Al 2 O 3. • The strong adsorption capacity of toluene and guaiacol occurs on Rh (2 0 0). • The routes for the hydrogenation of DPE, toluene and guaiacol are presented. Selective hydrogenation of arenes is a crucial process not only for the hydrogen storage and transport but also for the synthesis of important pharmaceutical intermediates. Herein, a series of α-Al 2 O 3 -supported catalysts prepared using different metals were tested for the arenes hydrogenation of lignin derivatives at room temperature. The kinetic studies reveal that Rh-1/α-Al 2 O 3 exhibits both the highest reaction rate and TOF value for the conversion of diphenyl ether and toluene. The XRD, TEM, XPS and XAS characterizations suggest that the metal Rh nanoparticles dispersed on α-Al 2 O 3 support for Rh-1/α-Al 2 O 3 catalyst is mainly responsible for the H 2 activation/dissociation and subsequent arenes hydrogenation. The density functional theory calculation indicates the stronger adsorption capacity of toluene and guaiacol on Rh (2 0 0) than that on Rh (1 1 1) and Rh (2 2 0). Stable Rh-1/α-Al 2 O 3 can contribute to the improvement of the arenes hydrogenation of lignin derivatives to produce high-value-added platform chemicals at room temperature. [ABSTRACT FROM AUTHOR]