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The synthesis of 2,5-dimethylfuran (DMF) from 5-hydroxymethylfurfural (HMF) is a highly attractive route to a renewable fuel. However, achieving high yields in this reaction is a substantial challenge. Here it is described how PtCo bimetallic nanoparticles with diameters of 3.6 ± 0.7 nm can solve this problem. Over PtCo catalysts the conversion of HMF was 100% within 10 min and the yield to DMF reached 98% after 2 h, which substantially exceeds the best results reported in the literature. Moreover, the synthetic method can be generalized to other bimetallic nanoparticles encapsulated in hollow carbon spheres.

In cracking from: Highly engineered bifunctional yolk-shell nanocatalysts with tailored structural configuration, that is, hollow carbon spheres as the matrix, entrapped magnetite nanoparticles in the core, and in situ formed and highly dispersed noble metal nanoparticles within the carbon shells as active catalytic sites, were prepared. These nanocatalysts show high activity, reusability, and good magnetic separation properties.

Hydrodeoxygenation (HDO) is an attractive route for the upgrading of bio-oils produced from lignocellulose. Current catalysts require harsh conditions to effect HDO, decreasing the process efficiency in terms of energy and carbon balance. Herein we report a novel and facile method for synthesizing bimetallic PtCo nanoparticle catalysts (ca. 1.5 nm) highly dispersed in the framework of nitrogen-doped ordered mesoporous carbon (NOMC) for this reaction. We demonstrate that NOMC with either 2D hexagonal (p6m) or 3D cubic (Im3‾ m) structure can be easily synthesized by simply adjusting the polymerization temperature. We also demonstrate that PtCo/NOMC (metal loading: Pt 9.90 wt %; Co 3.31 wt %) is a highly effective catalyst for HDO of phenolic compounds and "real-world" biomass-derived phenolic streams. In the presence of PtCo/NOMC, full deoxygenation of phenolic compounds and a biomass-derived phenolic stream is achieved under conditions of low severity.

Porous carbon monoliths with defined multilength scale pore structures, a nitrogen-containing framework, and high mechanical strength were synthesized through a self-assembly of poly(benzoxazine-co-resol) and a carbonization process. Importantly, this synthesis can be easily scaled up to prepare carbon monoliths with identical pore structures. By controlling the reaction conditions, porous carbon monoliths exhibit fully interconnected macroporosity and mesoporosity with cubic Im3m symmetry and can withstand a press pressure of up to 15.6 MPa. The use of amines in the synthesis results in a nitrogen-containing framework of the carbon monolith, as evidenced by the cross-polarization magic-angle-spinning NMR characterization. With such designed structures, the carbon monoliths show outstanding CO(2) capture and separation capacities, high selectivity, and facile regeneration at room temperature. At ~1 bar, the equilibrium capacities of the monoliths are in the range of 3.3-4.9 mmol g(-1) at 0 °C and of 2.6-3.3 mmol g(-1) at 25 °C, while the dynamic capacities are in the range of 2.7-4.1 wt % at 25 °C using 14% (v/v) CO(2) in N(2). The carbon monoliths exhibit high selectivity for the capture of CO(2) over N(2) from a CO(2)/N(2) mixture, with a separation factor ranging from 13 to 28. Meanwhile, they undergo a facile CO(2) release in an argon stream at 25 °C, indicating a good regeneration capacity.

The growth of α-Al2O3 nanofibers was observed using mesoporous carbon aerogels as substrate and aluminium nitrate as Al2O3 source based on a carbothermal route. The alumina fibers exhibit single crystal characteristics.