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Effective adsorption and speedy surface reactions are vital requirements for efficient active sites in catalysis, but it remains challenging to maximize these two functions simultaneously. We present a solution to this issue by designing a series of atom-pair catalytic sites with tunable electronic interactions. As a case study, NO selective reduction occurring on V

The electrocatalytic nitrogen reduction reaction (NRR) on metal-free catalysts is an attractive alternative to the industrial Haber-Bosch process. However, the state-of-the-art metal-free electrocatalysts still suffer from low Faraday efficiencies and low ammonia yields. Herein, we present a molecular design strategy to develop a defective boron carbon nitride (BCN) catalyst with the abundant unsaturated B and N atoms as Lewis acid and base sites, which upgrades the catalyst from a single "Lewis acid catalysis" to "frustrated Lewis pairs (FLPs) catalysis."

Guided by in situ synchrotron X-ray diffraction (SXRD) measurements and quantitative analysis, we identified and synthesized a new type of lithium nickel oxide as a cathode material for Li-ion batteries. This compound is a composition of two crystallographic components: a major stoichiometric layer-structured phase, LiNiO2, and a minor Li-containing disordered rock-salt phase, LiδNi1-δO, both embedded in the same cubic close-packed oxygen lattice. The LiNiO2|LiδNi1-δO composite, when used as the active material in a cathode, delivers high energy density, superior rate capability, and long-term cycling stability owing to its unique structural configuration.

The ammoximation of cyclohexanone using preformed hydrogen peroxide (H 2 O 2 ) is currently applied commercially to produce cyclohexanone oxime, an important feedstock in nylon-6 production. We demonstrate that by using supported gold-palladium (AuPd) alloyed nanoparticles in conjunction with a titanium silicate-1 (TS-1) catalyst, H 2 O 2 can be generated in situ as needed, producing cyclohexanone oxime with >95% selectivity, comparable to the current industrial route. The ammoximation of several additional simple ketones is also demonstrated. Our approach eliminates the need to transport and store highly concentrated, stabilized H 2 O 2 , potentially achieving substantial environmental and economic savings. This approach could form the basis of an alternative route to numerous chemical transformations that are currently dependent on a combination of preformed H 2 O 2 and TS-1, while allowing for considerable process intensification.

The ammoximation of cyclohexanone using preformed hydrogen peroxide (H

Ni-rich layered oxide cathode materials, such as LiNi0.83Co0.12Mn0.05O2 (NCM811), exhibit high specific capacity and low cost, and become cathode material preference of high-energy-density Li-ion batteries. However, these cathode materials are not stable and will form Li-poor reconstructed layers and alkaline compounds (Li2CO3, LiOH) on the surface during the storage and processing in humid air, resulting in serious deterioration of electrochemical properties. During the past two decades, the consensus on the surface instability mechanism during humid air storage has not been reached. The main controversy focuses on the unstable octahedron mechanism and the Li/H exchange mechanism. Herein, we investigate the instability mechanism in the humid air by conducting scanning electronic microscopy, scanning transmission electron microscopy, and x-ray photoelectron spectroscopy analysis on NCM811 samples stored in designed atmospheres, etc., and realize that the surface instability of the NCM811 during storage should be mainly originated from Li/H exchange when it contacts with moisture.