Single-atom catalysts (SACs) have attracted much attention due to their outstanding catalytic performance in heterogeneous catalysis. Here, we report a template sacrificial method to fabricate an atomically dispersed Co catalyst; three kinds of silica templates with different microstructures (MCM-41, SBA-15, and FDU-12) were employed and the effect of pore structure of the templates on the dispersity of Co was investigated. The catalysts fabricated with different templates presented different Co dispersities, leading to distinguishing catalytic performance. The optimized Co 1 @NC-(SBA) catalyst with atomically dispersed Co displayed outstanding catalytic activity for the hydrodeoxygenation (HDO) of lignin-derived species as well as the hydrogenation of various nitroaromatics. The reaction mechanism of the HDO of vanillin was investigated by using density functional theory calculations as well.

The catalytic performance of metal particles is closely related to the particle size. In this article, ultrafine palladium nanoparticles anchored on nitrogen-doping carbon support (Pd/N-XC72R) were fabricated, wherein the N-XC72R was prepared through low-temperature annealing of Vulcan XC72R carbon with urea at 300 °C. Nitrogen dopant on the surface of carbon support can remarkably strengthen the affinity of the metal nanoparticles onto the support. Compared with the Vulcan XC-72R-supported Pd catalyst, the prepared Pd/N-XC72R delivered superior catalytic activity for the transfer hydrogenation of nitroarenes with formic acid as the hydrogen donor at ambient temperature. Our strategy may provide an effective and feasible approach to fabricate N-functionalized carbon materials and construct high-performance ultrasmall metal nanoparticle heterogeneous catalysts.

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The non‐precious metal catalysts with high catalytic activity is extremely desirable but still full of challenges. In this paper, CoCu bimetal immobilized on nitrogen‐doped porous carbon (CoCu‐N‐C) was prepared by an effective ligand‐stabilized pyrolysis strategy. CoCu‐N‐C exhibited excellent catalytic efficiency for the transfer hydrogenation of nitroarenes with ammonia borane as hydrogen source, which can be ascribed to the well dispersed metal nanoparticles, the synergetic interaction of CoCu bimetal and nitrogen‐doped carbon. The durability and recyclability experiments of the recycled CoCu‐N‐C catalyst indicated that no obvious change in catalytic performance was observed after five consecutive cycles. To gain insight into the catalytic mechanism of CoCu‐N‐C for the hydrogenation reaction, density functional theory calculations was also conducted. This work provides an universal approach for constructing highly efficient non‐precious metal heterogeneous catalysts and which may find diverse high performance applications.

Graphitic carbon nitride (g-C 3 N 4) and graphene (GO) have been greatly utilized as supports in the field of heterogeneous catalysis. In this work, layered C 3 N 4 polymer/graphene hybrid (CNNS/rGO 20) with heterostructure was fabricated by a hydrothermal method followed by loading Pd nanoparticles on the hybrid. The palladium was well dispersed uniformly (1.31 nm) owing to the layered and porous heterostructure of CNNS/rGO 20. The obtained catalyst was used for the transfer hydrogenation of a series of nitro-compounds to give the corresponding aromatic amines with outstanding activity by employing formic acid as hydrogen donor under mild conditions. The catalytic activity of the heterogeneous catalyst showed no significant loss after five continuous use.