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We report am ethod for the electrochemical deuteration of a,b-unsaturated carbonyl compounds under catalystand external-reductant-free conditions,w ith deuteration rates as high as 99 %a nd yields up to 91 %i n2h. The use of graphite felt for both the cathode and the anode was key to ensuring chemoselectivity and high deuterium incorporation under neutral conditions without the need for an external reductant. This method has an umber of advantages over previously reported deuteration reactions that use stoichiometric metallic reductants.M echanistic experiments showed that O 2 evolution at the anode not only eliminates the need for an external reductant but also regulates the pH of the reaction mixture,keeping it approximately neutral.

Constructing the structure and composition of active sites of catalysts to discriminate between reaction molecules remains a grand challenge in heterogeneous catalysis, as the ability to precisely control the interfacial chemistry within molecular-scale environments is largely lacking. Here, we recognize the reaction sites of thiolate-ligand protected gold nanoclusters for CO2 electroreduction (CO2RR) by cleaving the Au–S or C–S bonds selectively that can be controlled by Cd doping. Our study reveals that the C–S bond cleavage occurring on partial ligands leads to the creation of open S sites that are able to readily bind the CO2 molecule and catalyze its reduction, while the breaking of Au–S bonds creates exposed metal sites to favor H2 evolution that is considered as the main complete reaction of CO2RR. We further tailor the reactivities of these two types of reaction sites by only the ligand derivatization, which holds great promise in rational design of high-performance catalysts.

The discovery of atomically precise nanoclusters is generally unpredictable, and the rational synthesis of nanoclusters guided by the theoretical design is still in its infancy. Here we present a de novo design of Au 36 (SR) 24 nanoclusters, from theoretical prediction to experimental synthesis and characterization of their physicochemical properties. The crystal structure of an Au 36 (SR) 24 nanocluster perfectly matches the simulated structural pattern with Au 4 tetrahedral units along a two-dimensional growth. The Au 36 (SR) 24 nanocluster indeed differs from its structural isomer whose kernel is dissected in an Au 4 tetrahedral manner along a one-dimensional growth. The structural isomerism in the Au 36 (SR) 24 nanoclusters further induces distinct differences in ultrafast electron dynamics and chirality. This work will not only promote the atomically precise synthesis of nanoclusters enlightened by theoretical science, but also open up exciting opportunities for underpinning the widespread applications of structural isomers with atomic precision.

As a carbon‐free and sustainable fuel, ammonia serves as high‐energy‐density hydrogen‐storage material. It is important to develop new reactions able to utilize ammonia as a hydrogen source directly. Herein, we report an electrochemical hydrogenation of alkenes, alkynes, and ketones using ammonia as the hydrogen source and carbon electrodes. A variety of heterocycles and functional groups, including for example sulfide, benzyl, benzyl carbamate, and allyl carbamate were well tolerated. Fast stepwise electron transfer and proton transfer processes were proposed to account for the transformation.

It is an obstacle to precisely manipulate a doped heteroatom into a desired position in a metal nanocluster. Herein, we overcome this difficulty to obtain Pt 1 Au 37 (SCH 2 Ph t Bu) 24 and Pt 2 Au 36 (SCH 2 Ph t Bu) 24 nanoclusters via controllably doping Pt atoms into the kernels of Au 38 (SCH 2 Ph t Bu) 24 . We reveal that asymmetrical doping of one Pt atom into either of the cores of Au 38 (SCH 2 Ph t Bu) 24 elevates the relative energy of the HOMO (highest occupied molecular orbital) accompanied by one valence

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The work shows the evolution from monomeric Au24Au20 into dimeric Au43Ag38 nanoclusters and provides exciting opportunities for atomic manufacturing on metal nanoclusters to construct structures and functionality.