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Selectivity control is a challenging goal in Fischer–Tropsch (FT) synthesis. Hydrogenolysis is known to occur during FT synthesis, but its impact on product selectivity has been overlooked. Demonstrated herein is that effective control of hydrogenolysis by using mesoporous zeolite Y‐supported cobalt nanoparticles can enhance the diesel fuel selectivity while keeping methane selectivity low. The sizes of the cobalt particles and mesopores are key factors which determine the selectivity both in FT synthesis and in hydrogenolysis of n‐hexadecane, a model compound of heavier hydrocarbons. The diesel fuel selectivity in FT synthesis can reach 60 % with a CH4 selectivity of 5 % over a Na‐type mesoporous Y‐supported cobalt catalyst with medium mean sizes of 8.4 nm (Co particles) and 15 nm (mesopores). These findings offer a new strategy to tune the product selectivity and possible interpretations of the effect of cobalt particle size and the effect of support pore size in FT synthesis.

Bifunctional Fischer-Tropsch (FT) catalysts that couple uniform-sized Co nanoparticles for CO hydrogenation and mesoporous zeolites for hydrocracking/isomerization reactions were found to be promising for the direct production of gasoline-range (C5-11 ) hydrocarbons from syngas. The Brønsted acidity results in hydrocracking/isomerization of the heavier hydrocarbons formed on Co nanoparticles, while the mesoporosity contributes to suppressing the formation of lighter (C1-4 ) hydrocarbons. The selectivity for C5-11 hydrocarbons could reach about 70 % with a ratio of isoparaffins to n-paraffins of approximately 2.3 over this catalyst, and the former is markedly higher than the maximum value (ca. 45 %) expected from the Anderson-Schulz-Flory distribution. By using n-hexadecane as a model compound, it was clarified that both the acidity and mesoporosity play key roles in controlling the hydrocracking reactions and thus contribute to the improved product selectivity in FT synthesis.

Mechanical properties and geometries of printed products have been extensively studied in metal 3D printing. However, chemical properties and catalytic functions, introduced by metal 3D printing itself, are rarely mentioned. Here we show that metal 3D printing products themselves can simultaneously serve as chemical reactors and catalysts (denoted as selfcatalytic reactor or SCR) for direct conversion of C1 molecules (including CO, CO 2 and CH 4) into high value-added chemicals. The Fe-SCR and Co-SCR successfully catalyze synthesis of liquid fuel from Fischer-Tropsch synthesis and CO 2 hydrogenation; the Ni-SCR efficiently produces syngas (CO/H 2) by CO 2 reforming of CH 4. Further, the Co-SCR geometrical studies indicate that metal 3D printing itself can establish multiple control functions to tune the catalytic product distribution. The present work provides a simple and low-cost manufacturing method to realize functional integration of catalyst and reactor, and will facilitate the developments of chemical synthesis and 3D printing technology.

It is still a challenge to realize highly efficient conversion of CO 2 to a single target chemical. Herein, substantial progress has been made, both in catalyst design and reaction route exploration, for the direct conversion of CO 2 to ethanol. An alkene synthesis Na-Fe@C catalyst was integrated with another potassium-doped methanol synthesis CuZnAl catalyst to realize the direct conversion of CO 2 (39.2%) to ethanol (35.0%) selectively, accompanied by some useful alkene formation (33.0%). More in-depth in situ characterizations and density functional theory (DFT) calculations suggested that the unique catalytic interfaces, intimacy modes of the multifunctional catalysts, as well as the intermediate of aldehyde species played vital roles in the higher conversion rate of CO 2 to ethanol. Moreover, the multifunctional catalyst is easy to fabricate, regenerate, and recycle, being very close to the real industry application. Therefore, this work is promising to enrich the horizon of the economical utilization of CO 2 for renewable chemical synthesis.

Selectivity control is ac hallenging goal in Fischer-Tropsch (FT) synthesis.H ydrogenolysis is knownt oo ccur during FT synthesis,b ut its impact on product selectivity has been overlooked. Demonstrated herein is that effective control of hydrogenolysis by using mesoporous zeolite Y-supported cobalt nanoparticles can enhance the diesel fuel selectivity while keeping methane selectivity low. The sizes of the cobalt particles and mesopores are key factors whichd etermine the selectivity both in FT synthesis and in hydrogenolysis of nhexadecane,amodel compound of heavier hydrocarbons.The diesel fuel selectivity in FT synthesis can reach 60 %with aCH 4 selectivity of 5% over aN a-type mesoporous Y-supported cobalt catalyst with medium mean sizes of 8.4 nm (Co particles) and 15 nm (mesopores). These findings offer an ew strategy to tune the product selectivity and possible interpretations of the effect of cobalt particle sizea nd the effect of support pore sizei nF Tsynthesis.Fischer-Tropsch (FT) synthesis,aprocess for the conversion of syngas (CO/H 2 )d erived from nonpetroleum carbon resources such as natural gas (also shale gas), coal, and biomass,i nto hydrocarbon fuels and chemicals,h as received renewed interest because of the growing global demand for liquid fuels and the depletion of petroleum. Extensive studies have been devoted to developing efficient catalysts for FT synthesis, [1] but the effective control of product selectivity remains one of the grand challenges.T he FT products generally follow the Anderson-Schulz-Flory (ASF) distribution, which is unselective for the middle-distillate products. [1b] Fore xample,t he selectivities of products in gasoline (C 5-11 ) and diesel (C 10-20 )f ractions are limited to 45 and 39 %, respectively.Conventionally,the FT products are subjected to further hydrotreatment to increase liquid fuel selectivity. Compared to this two-stage process,the direct production of specific-range liquid fuels would be more energy and cost efficient.Recently,bifunctional FT catalysts,which combine either ruthenium, cobalt, or iron nanoparticles for CO hydrogenation, and acid sites in az eolite like H-ZSM-5 for hydrocracking,h ave been harnessed to enhance the C 5-11 selectivity. [2,3] However,few studies have succeeded in the direct and selective production of C 10-20 hydrocarbons, [4] even though the FT-based diesel fuel is known to possess many advantages such as low sulfur and aromatic content, and reduced NO x and particulate matter emissions. [5] Herein, we report an ew strategy to improve the C 10-20 selectivity by effective control of hydrogenolysis.We expected that the use of zeolite H-Y,having aweaker Brønsted acidity than H-ZSM-5, might cause milder hydrocracking of heavier primary hydrocarbons formed on FT metals and lead to higher C 10-20 selectivity.H owever,the Co/ H-Y catalyst did not show enhanced C 10-20 selectivity compared to that of Co/SiO 2 and Co/Al 2 O 3 ,w hich are two conventional FT catalysts,b ut its C 21+ selectivity was lower because of the Brønsted a...

Cu-based bimetallic catalysts have been studied in the electrocatalytic nitrate (NO3 –) reduction reaction (NO3 –RR) for a long time. However, few studies have focused on horizontal comparison of CuNi, CuCo, and CuFe (abbreviated as CuM) bimetallic catalysts in electrocatalytic NO3 –RR for ammonia synthesis. Herein, we prepare the three series of Cu-based bimetallic catalysts, with different atom ratios of Cu/M (Cu/M = 7/3, 5/5, or 3/7) and ordered mesoporous carbon (OMC) as support (denoted as CuM/OMC). The characterization results reveal that the metallic particles of Cu and M components possess an intimate relationship on the CuM/OMC catalysts. The electrocatalytic NO3 –RR performance uncovers that the optimal NH3 yield rates of CuM/OMC catalysts at −0.8 V (vs reversible hydrogen electrode (RHE)) follow this order: Cu5Fe5/OMC > Cu5Co5/OMC > Cu7Ni3/OMC > Cu/OMC > Fe/OMC > Co/OMC > Ni/OMC > OMC. The bimetallic CuM/OMC catalysts exhibit higher NH3 yield rates than the monometallic catalysts. This is attributed to strong synergistic effects between the Cu and M components. We expect that these insights can stimulate new developments of bimetallic catalysts in electrocatalysis.