Search

Due to the synergistic effects of different metal sites, the double atom or multiple atomic catalysts are very promising for use in electrocatalysis. This paper focuses on the synthesis of urea [CO(NH2)2] under the synergistic effects of bimetallics. The heteronuclear diatomic molecular catalysts were designed and screened, and the details and energy information of the elementary reactions were provided from the atomic level using theoretical simulation, which provided a new understanding for the study of the reaction mechanism. It was found that the NbVN6C catalyst was the best catalyst for the electrosynthesis of CO(NH2)2 (0.37 eV < 0.44 eV < 0.67 eV < 0.74 eV < 0.84 eV for NbVN6C, TaVN6C, WVN6C, MoVN6C, ReVN6C, respectively), and the optimal path was * → *N2 → *NN → *NNH → *NNH2 → *HNNH2 → *H2NNH2 → *H2NNH2–CO2 → *H2NNH2–COOH → *H2NCONH2. At the same time, compared with the homonuclear diatomic catalyst V2N6C, the heteronuclear diatomic molecular catalyst NbVN6C had a smaller limiting potential (−0.37 V and −0.59 V), which demonstrated the usefulness of this study. [ABSTRACT FROM AUTHOR]

Owing to the advantage of atomic utilization, the single-atom catalyst has attracted much attention and been employed in multifarious catalytic reactions. Its definite site configuration is favorable for exploring the actual active centers and corresponding reaction mechanism. At the atomic scale, the tunable site configuration, from central metal atoms, coordinated heteroatoms, peripheral dopants, and feasible polymetallic centers to the synergetic intrinsic carbon defects, can effectively augment the intrinsic activity for oxygen reduction reaction (ORR). From a practical viewpoint, the propagation strategies of single-atom sites, the loading-activity relation and the structural retention during practical tests are crucial for the industrial applications. Furthermore, the activity contribution of multiple additional active centers including the active carbon sites and the pony-size well-wrapped metal species should be acknowledged. From the perspective mentioned above, this paper thoroughly analyses the consensuses, controversies, challenges and possible solutions based on the current research progress, thereby providing inspiration and guidance for the active center engineering of single-atom catalysts. [ABSTRACT FROM AUTHOR]

Single-atom catalysts (SACs) with atomically dispersed metals have emerged as a new class of heterogeneous catalysts and have attracted considerable interest because they offer 100% metal atom utilization and show excellent catalytic behavior compared with traditionally supported nano-particles. However, it is challenging to explore the active sites and catalytic mechanisms of SACs through common characterization methods due to the isolated single atoms. Therefore, employing theoretical calculations to determine the nature of SACs' active sites and the reaction mechanisms is particularly meaningful. This paper describes the nature of SACs by summarizing the diverse applications and properties of SACs, which starts from computational simulation on a couple of important applications of SACs. Then the distinctive and fundamental properties of SACs are discussed. At last, the challenges and future perspectives of computational calculations for SACs are outlined. [ABSTRACT FROM AUTHOR]

Palladium-catalyzed transformations of aryl halides and pseudo-halides involving carbonylation, carbon–carbon and carbon–heteroatom bond-forming reactions, etc. are very well documented, and have already been reviewed several times. The metal-catalyzed activation of benzylic derivatives is much less described. However, during the last decades, a number of papers have shown the interest offered by benzylic derivatives (halides, carbonates, acetates, phosphonates) in selective catalytic reactions for organic synthesis, most of them in the presence of palladium catalysts. The purpose of this tutorial review is to highlight selected examples of palladium-catalyzed transformations involving reactive benzylic derivatives. [ABSTRACT FROM AUTHOR]

In this paper, polymer nanocapsules embedded with noble metal nanoparticles and showing a good catalytic activity were prepared by a novel and convenient method. [ABSTRACT FROM AUTHOR]