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N-Doped mesoporous carbons (NMCs) with extra framework magnesium were prepared by a one-pot method and used as supports for Pt catalysts. The surface basicity of NMC improved in the presence of extra framework magnesium (e.g., –Ph–O–Mg), meanwhile, the electron density of Pt was enriched by the electron transfer from graphitic N in NMC to Pt. As a result, the catalytic activity of the supported Pt catalyst was improved to be able to selectively oxidize glycerol (GLY) to tartronic acid (TA) under base-free conditions. [ABSTRACT FROM AUTHOR]

Pt supported on KOH-activated mesoporous carbon (K-AMC) was used to catalyze glycerol oxidation under base-free conditions at room temperature. To study the relationship between the carbon surface chemistry and the catalytic performance of the K-AMC-based Pt catalysts, different levels of surface oxygen functional groups (SOFGs) on the AMC supports were induced by thermal treatment at different temperatures under inert or H2 gas. A strong effect of the surface chemistry was observed on AMC-supported Pt catalysts for glycerol oxidation. The presence of carboxylic acid groups impedes the adsorption of glycerol, which leads to the reduction of catalytic activity, whereas the presence of high-desorption-temperature SOFGs, such as phenol, ether, and carbonyl/quinone groups, provide hydrophilicity to the carbon surface that improves the adsorption of glycerol molecules on Pt metal surface, which is beneficial for the catalytic activity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Cu x O exist in N-doped porous carbon in a highly dispersed state due to the strong interaction between Cu x O and the N atoms. • The surface Cu+ instead of Au nanoparticles activates O 2 to produce active oxygen species. • The catalyst exhibits excellent catalytic activity and selectivity in glycerol oxidation. In this work, N-doped porous carbon stabilized Cu x O (Cu-NPCs) were synthesized by a one-pot method using copper nitrate as copper precursor with the aid of Pluronic F127 under acidic condition. The characterization results confirmed that Cu x O species (CuO and Cu 2 O) existed in NPC in a highly dispersed state due to the strong interaction between Cu x O and the doped N atoms. The obtained Cu-NPCs were used as supports to prepare Au catalysts for glycerol (GLY) oxidation to dihydroxyacetone (DHA) under base-free conditions. During the reaction, GLY preferentially adsorbed onto Au nanoparticles via the secondary OH groups due to the porous characteristics of the supports, the enhanced surface basicity from the N functionalities accelerates the alkoxide formation by abstracting proton from GLY, and the surface Cu+ sites instead of Au nanoparticles activate O 2 molecules to produce active oxygen species, as a result, Au/Cu-NPC-15 %-H, which is the best catalyst in Au/Cu-NPCs, exhibited much higher catalytic activity and selectivity than those of Au/CuO. Moreover, due to the stabilization of Cu x O species by NPC, relatively stable surface Cu+ content, and the strong interaction between Au nanoparticles and the supports, Au/Cu-NPC-15 %-H also possessed much better catalytic stability than that of Au/CuO during four consecutive catalytic runs. [ABSTRACT FROM AUTHOR]

Catalytic transfer hydrogenation using glycerol (GLY) as a hydrogen donor presents a sustainable and secure approach for hydrogenation of quinoline and its derivatives. Conventional non-noble metal catalysts can effectively catalyze the transfer hydrogenation reaction with GLY. However, it is inevitable that metal leaching occurs under alkaline hydrothermal conditions. In this work, N-doped carbon encapsulated non-noble metal catalysts, such as Co@NC, Ni@NC, and CoNi@NC, were prepared by one-pot method combined with an acid leaching for this reaction. According to Mott-Schottky effect, encapsulating of Co, Ni, and CoNi nanoparticles with relatively smaller work function in NC shells constructed a rectifying contact and increased the electron density on NC shells. Density Functional Theory (DFT) calculations confirm that electrons transfer from metal cores to NC shell, with CoNi transferring the most, followed by Co and Ni. As a result, the catalytic activity followed the order of CoNi@NC＞Co@NC＞Ni@NC, where CoNi@NC exhibited highest catalytic activity, 92.2% GLY conversion and full quinoline conversion can be obtained over CoNi@NC at 180 °C with 89.7% and 99.3% of the selectivity to lactic acid and 1, 2, 3, 4-tetrahydroquinoline, respectively. In addition, CoNi@NC possessed excellent stability because NC shells physically isolate metal cores from the reactive environment. Such Mott-Schottky catalyst tuning could be an efficient way to design new non-noble catalysts. [Display omitted] • Catalytic transfer hydrogenation of quinoline and its derivatives with glycerol is a sustainable and secure approach. • Encapsulating of Co, Ni, and CoNi nanoparticles in NC shells constructed a rectifying contact by Mott-Schottky effect. • The catalytic activity of Ni@NC, Co@NC, and CoNi@NC is linearly correlated with the number of transferred electrons. • The high electron density on NC shells enhanced the adsorption/desorption, improving the catalytic activity. [ABSTRACT FROM AUTHOR]

• The relationship of the d -band center and catalytic activity of exhibits volcano-shape behavior. • 85.4% of GLY conversion with 67.3% yield of lactate and 56.5% yield of formate can be achieved at 200 °C over Pd2Pt1/NCSWCs. • The adsorption and dissociation energy of h species can reach a balance on Pd2Pt1/NCSWCs. • The wrinkled cages in the support NCSWCs can provide large storage space and act as great artificial reactors. Catalytic transfer hydrogenation of bicarbonate, a typical product of CO 2 captured in an alkaline solution, with glycerol (GLY) as a hydrogen donor to formate (FA) and lactate (LA) is a sustainable and green approach for simultaneous valorization of CO 2 and the major byproduct from biodiesel production. Conventional monometallic noble metal catalysts can catalyze this transfer hydrogenation reaction, but generally required a high reaction temperature, leading to a low yield of FA. In this work, N-doped carbon spheres with wrinkled cages (NCSWCs) supported PdPt alloy catalysts were prepared and their electronic structures were determined by Valence Band Spectra (VBS) and Density Functional Theory (DFT). It was found that the relationship between the d band center and catalytic activity exhibits volcano-shaped behaviors, where Pd 2 Pt 1 /NCSWCs is on the top of the curve, 85.4% of GLY conversion with 67.3% yield of LA and 56.5% yield of FA can be achieved at 200 °C. DFT calculations also revealed that Pd 2 Pt 1 /NCSWCs possessed an intermediate d band center, which tunes the adsorption and dissociation energy of H species on its surface, allowing maximum H transfer during the transfer hydrogenation of bicarbonate, leading to high catalytic activity. Such a d band center catalyst tuning could be efficient way to design new catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]