TY - JOUR

T1 - Role of steps in N-2 activation on Ru(0001)

A1 - Dahl,Søren

A1 - Logadottir,Ashildur

A1 - Egeberg,Rasmus

A1 - Nielsen,Jane Hvolbæk

A1 - Chorkendorff,Ib

A1 - Törnqvist,Eric

A1 - Nørskov,Jens Kehlet

AU - Dahl,Søren

AU - Logadottir,Ashildur

AU - Egeberg,Rasmus

AU - Nielsen,Jane Hvolbæk

AU - Chorkendorff,Ib

AU - Törnqvist,Eric

AU - Nørskov,Jens Kehlet

PB - American Physical Society

PY - 1999

Y1 - 1999

N2 - Using adsorption experiments and density functional calculations we show that N-2 dissociation on the Ru(0001) surface is totally dominated by steps. The measured adsorption rate at the steps is at least 9 orders of magnitude higher than on the terraces at 500 K, and the corresponding calculated difference in activation energy is 1.5 eV. The low barrier at the step is shown to be due to a combination of electronic and geometrical effects. The consequences for Ru as a catalyst for ammonia synthesis are discussed.

AB - Using adsorption experiments and density functional calculations we show that N-2 dissociation on the Ru(0001) surface is totally dominated by steps. The measured adsorption rate at the steps is at least 9 orders of magnitude higher than on the terraces at 500 K, and the corresponding calculated difference in activation energy is 1.5 eV. The low barrier at the step is shown to be due to a combination of electronic and geometrical effects. The consequences for Ru as a catalyst for ammonia synthesis are discussed.

KW - DESORPTION

KW - AU

KW - ENERGY

KW - GROWTH

KW - ADSORPTION

KW - SURFACES

KW - SINGLE-CRYSTAL

KW - AMMONIA-SYNTHESIS

KW - DISSOCIATIVE CHEMISORPTION

UR - http://link.aps.org/doi/10.1103/PhysRevLett.83.1814

U2 - 10.1103/PhysRevLett.83.1814

DO - 10.1103/PhysRevLett.83.1814

JO - Physical Review Letters

JF - Physical Review Letters

SN - 0031-9007

IS - 9

VL - 83

SP - 1814

EP - 1817

ER -