Density functional theory study of hydrogenation of S to H₂S on Pt–Pd alloy surfaces

Abstract

In this work, the adsorption of S-containing species (S, HS, and H2S) and the hydrogenation of S on the Pt–Pd alloy were investigated by using the periodic density functional theory (DFT).

Adsorption and diffusion of sulfur on the (111), (100), (110), and (211) surfaces of FCC metals: Density functional theory calculations

“…These results are in line with previous calculations of the (111) surface. 2,4,9,16,17,22,25,26,[34][35][36] In the case of the (100) and (110) surfaces, the Hollow site is in general the most stable site. Similar results were previously reported 9,29,30 for the (110) and (100) surfaces.…”

“…Previous studies normally report the preferred sulfur adsorption binding site, the binding (adsorption) energy, the sulfur-surface interatomic distances, and the diffusion energy of sulfur. The preferred adsorption site and the binding energy have been reported for sulfur on Ni(111), 3,9,17,28,30,31 Cu(111), 9,[13][14][15]17,25,26,31,35 Rh(111), 17 Pd(111), 4,15,22,26,35 Ag(111), 2,15,17,25,35 Ir(111), 34 Pt(111), 4,17,37 Au(111), 15,16,22,26 Ni(110), 9 Cu(110), 5,9,13 Au(110), 21 Ni(100), 9,12,30 Cu(100), 9,12,14 Ir(100), 29 Au(100), 7,16 Pd(211), 36 and Au(211). 16 Th...…”

“…Density Functional Theory (DFT) calculations have been performed to study the adsorption of sulfur on the low-index surfaces of multiple Face Center Cubic (FCC) metals. [3][4][5]7,9,10,[12][13][14][15][16][17]21,22,25,26,[28][29][30][33][34][35][36][37] We surveyed the DFT calculations of sulfur on FCC metal surfaces reported since the year 2000; see Ref. 39 for an account of earlier calculations.…”

“…12 At a coverage of 0.25 ML or lower, the adsorbed species is atomic sulfur. 25 Sulfur is more stable when adsorbed on high coordination sites, like the three-fold FCC site on the (111) 4,9,16,17,22,31,26,25,[34][35][36] surface and the four-fold site on the (110) 9 and (100) 9,29,30 surfaces. Sulfur is strongly bound to surfaces of FCC metals; the calculated binding energy ranges from 6.0 eV in Ni 30 and Ir 29 to 3.5 eV in Au.…”

Chemical Strategies for Enhancing Activity and Charge Transfer in Ultrathin Pt Nanowires Immobilized onto Nanotube Supports for the Oxygen Reduction Reaction

“…It should be noted that DFT calculations describing both NH 2 and SH species adsorbed onto Pt (111) surfaces have suggested a bond strength value of 2.00 eV for −NH 2 species and of 2.31 eV for −SH species under similar modeling conditions, respectively. These computations would indicate that the interaction between Pt and S is likely to be stronger than that between Pt and N. , Furthermore, the overall bond strength of formate (COO – ) species adsorbed onto Pt is likely ∼2.54 eV, as individual constituent Pt–O bonds possess discrete bond strengths of 1.27 eV . As we have only utilized an acidic solution (0.1 M HClO 4 ) as our electrochemical environment in which to run our reactions, it is reasonable to assume that with carboxyl groups, the actual species connected to Pt atoms consists of −COO – as opposed to −COOH.…”