Figure 1
Concentrations of NH3 synthesized using various Ru/MgO-MOx catalyst as functions of temperature. (A) The addition of alkali metals and alkaline earth metals. The black dotted line corresponds to the equilibrium conversion. Color code: red line: lithium, green line: sodium, blue line: potassium, brown line: rubidium, purple line: cesium, gray squares: magnesium, orange line: calcium, light blue line: strontium, black line: barium. (B) The addition of transition metals (period 4). The black dotted line corresponds to the equilibrium conversion. Color code: red line: scandium, green line: titanium, blue line: vanadium, brown line: chromium, purple line: manganese, gray line: iron, orange line: cobalt, light blue line: nickel, black line: copper. (C) The addition of transition metals (period 5 and 6 without lanthanides). The black dotted line corresponds to the equilibrium conversion. Color code: red line: yttrium, green line: zirconium, blue line: niobium, brown line: molybdenum, purple line: rhodium, gray line: palladium, orange line: silver, light blue line: rhenium, black line: iridium, pink line: platinum. (D) The addition of Lanthanides. The black dotted line corresponds to the equilibrium conversion. Color code: red line: lanthanum, green line: cerium, blue line: praseodymium, brown line: neodymium, purple line: samarium, gray line: europium, orange line: gadolinium, light blue line: terbium, black line: dysprosium, pink line: holmium, yellow line: erbium, light green: thulium, pale blue line: ytterbium. (E) The addition of p-block elements and zinc. The black dotted line corresponds to the equilibrium conversion. Color code: red line: aluminum, green line: silicon, blue line: phosphorus, brown line: sulfur, purple line: zinc, gray line: gallium, orange line: indium, light blue line: tin, black line: tellurium, pink line: bismuth. Reaction conditions are described in the “Methods” section.
