Facile preparation of single-atom Ru catalysts via a two-dimensional interface directed synthesis technique for the NRR.

Through the catalysis system design of in situ Ru SACs (single atoms) anchored on a rGO/NC two-dimensional interface, we successfully realized the SA-Ru@rGO/NC electrocatalyst with high metal loading density at a relatively low temperature. The largest NH3 yield of 110.1 µg h-1 mgcat-1 and FE of 17.9% were achieved at -0.3 V under ambient conditions. The electronic environment of the catalyst was regulated by the electronic metal-support interaction, and the use of SACs had the advantages of inhibiting the hydrogen evolution reaction (HER) and enhancing N2 adsorption, which effectively improved the performance of electrocatalytic nitrogen fixation.

Modified high-efficiency carbon material for deep degradation of phenol by activating persulfate.

A series of cobalt-nitrogen modified catalysts were prepared and applied to the degradation of phenol. The Mott Schottky catalyst (CoO/NGr@C) with high pyridine nitrogen content was designed to activate potassium peroxodisulfate (PDS) to generate active free radicals for phenol degradation. The structural properties of the materials are analyzed by XPS, TEM and then the charge density calculation is performed by DFT, which proves the existence of the highly active interface effect. Co-N-CMCM-41 can only degrade phenol into benzoquinone and it is difficult to achieve further degradation of benzoquinone, while the modified CoO/NGr@C can achieve deep mineralization of the intermediate benzoquinone through UV spectrum. EPR was used to prove that both hydroxyl radicals and sulfate radicals exist in the degradation process of phenol. Through the DFT simulation calculation of the material, it is proved that the existence of carbon activated by nitrogen and the electron rearrangement between cobalt and nitrogen-rich carbon lead to the catalytic activity of the material. The degradation conditions of phenol were optimized and the reaction kinetics of further phenol degradation were studied. The activation energy of phenol degradation on CoO/NGr@C is calculated to be 34.38 kJ mol-1.

Oxidative esterification of renewable furfural on cobalt dispersed on ordered porous nitrogen-doped carbon.

A series of highly dispersed cobalt-based catalysts on N-doped ordered porous carbon (Co-NOPC) were synthesized using the sacrificial-template method. MCM-41, ZSM-5 and SBA-15 were employed as hard templates with 2,2'-bipyridine as the ligand. The physical and chemical properties of the Co-NOPC catalyst were characterized by Raman, XRD, SEM, TEM, EDX, ICP, BET, XPS. Co-NOPC had been proven to be a highly efficient catalyst for oxidative esterification of furfural (FUR) to methyl 2-furoate without alkaline additives. Catalytic performance was correlated to the dispersed cobalt, porous structure and specific surface area. The relationship between oxygen activation and the strong interaction of cobalt and pyridine nitrogen were confirmed by XPS. Catalytic performance enhancement mechanisms were correlated with the redistribution of electrons at the interface between carbon material and cobalt atoms through the molecular dynamics method and a reaction mechanism was also proposed. The optimized catalysts showed outstanding catalytic activity and stability and no obvious decrease in activity was found after 6 cycles with 99.6% FUR conversion and 96% methyl 2-furoate selectivity.

A Pd-TSH composite membrane reactor for one-step oxidation of benzene to phenol.

Pd membranes with excellent stability and flux were prepared by modified electroless plating, and a loose TSH zeolite with intraparticle hollows was joined on the Pd membrane by a covalent bonding method. The prepared Pd-TSH composite membrane shows outstanding performance for phenol production in the one-step oxidation of benzene to phenol.