Adsorption of thiophene and pyridine on W(110)

Low Temperature Deposition of WNxCyDiffusion Barriers Using WN(NEt2)3as a Single-Source Precursor

“…Pyridine has been shown to readily adsorb to and decompose on tungsten surfaces. 40 Therefore, this trend is likely the result of surface coordination by pyridine that interacts with the growing surface by occupying adsorption sites, effectively disrupting crystal growth. For pyridine, estimated crystallite domains increased in size from a minimum of 16.3 Å (350 • C) to a maximum of 28.8 Å (550…”

Reactive and Non-reactive Interactions of Thiophene with WS2 Fullerene-like Nanoparticles: An Ultra-high Vacuum Surface Chemistry Study

“…Thiophene already partially decomposes at 90 K on W(110) surface and more strongly when the surface temperature is increased to 200 K; carbon and sulfur have been detected on the surface as well as sulfur and hydrogen desorption [15]. Kinetic studies at high pressures of thiophene and hydrogen on supported and unsupported tungsten sulfide powders suggested the formation of H 2 S and butane as well as tetrahydrothiophene as parallel reaction pathways [16].…”

Pyridine adsorption and reaction on Mo(110) and C/N–Mo(110): experiment and modeling

“…The adsorption modes studied include: parallel adsorption as g 1 (N)-Py-0°(structure Py1), l 2 ,g 1 (N)-Py-0°(structure Py5), g 6 -Py-0°(structure Py7); titled adsorption as g 1 (N)-Py-30°(structure Py2) and g 1 (N)-Py-45°(structure Py3); and perpendicular adsorption as g 1 (N)-Py-90°(structure Py4), l 2 ,g 1 (N)-Py-90°(structure Py6), l 3 ,g 1 (N)-Py-90°( structure Py8), l 2 ,g 2 (N,C2)-Pyridyl (structure Py9) and g 1 (C2)-Pyridyl (structure Py10). These initial geometries reflect the most prevalent pyridine adsorption modes in organometallic chemistry [4], as well as the many proposed tilted bonding geometries [13,22,23,29] on metal sur- faces. Pyridine and the Mo(1 1 0) surface were fully optimized prior to adsorption calculations.…”

“…In general, these studies concluded that pyridine adsorption geometry is surface coverage dependent, which is supported by three bonding geometries; parallel to the surface at low coverages (g 6 -Py-0°) [15,20,23,[28][29][30], perpendicular or inclined at high coverages (g 1 (N)-Py-90°) [13][14][15][16]20,22,23,[28][29][30][31], and through apyridyl species formation, which requires bond formation between the nitrogen and an adjacent carbon with the metal surface (g 2 (N,C2)-Pyridyl) [14,15,20,27,30,31]. Grassian and Muetterties [15] showed through electron energy loss and thermal decomposition spectroscopy of pyridine adsorption on Pt(1 1 1) that two adsorption modes are present at low temperature, namely through the nitrogen atom (g 1 (N)-Py-90°) and the p and p* orbitals of the pyridine ring (g 6 -Py-0°).…”

“…Nitrogen accumulation on the surface initially undergoes a slight increase, and then remains nearly constant for subsequent pyridine doses. Neither ammonia (m/z = 17) nor nitrogen (m/z = 28) were detected as desorbing species [29,42]; therefore, nitrogen either diffused into the bulk [43] or the desorbing nitrogen products were below the sensitivity of the mass spectrometer used in the present study. The local bonding environment of surface carbon may be distinguished by considering AES line shapes [44], leading to the identification of carbidic or graphidic surface carbon species.…”