Flash desorption and equilibration of H2 and D2 on single crystal surfaces of platinum

Elucidation of the active surface and origin of the weak metal–hydrogen bond on Ni/Pt(111) bimetallic surfaces: a surface science and density functional theory study

“…The kinetic parameters for desorption are typically determined by a Redhead analysis of the peak desorption temperatures observed in a TPD experiment as a function of coverage at a constant heating rate [17]. The desorption of H 2 from Pt(1 1 1) however, has defied this straightforward interpretation for almost 30 years, with reports of multiple binding sites, pre-exponential factors varying over 6 orders of magnitude, desorption barriers varying by factors of 2 and even disagreement on the order of desorption [18][19][20][21]. Our results for H 2 desorption from Ni/Pt surfaces were also not compatible with a single, second order desorption event.…”

Weakly-bound hydrogen on defected Pt(111)

“…In early work, Lu and Rye [30] also reported a single-peaked H 2 desorption from Pt(111), but their H 2 dose (40 L) and H coverage (0.75 ML) were well below the saturation values (10 3 -10 5 L and 1 ML) [28] required for the full population of the β 1 -H state observed by others [23,25,26]. They also observed double-peaked H 2 desorption from Pt(100), Pt(110) and Pt(211), but with varying peak temperatures.…”

Revisiting H/Pt(111) by a combined experimental study of the H-D exchange reaction and first-principles calculations

“…However, Baldwin and Hudson [27] concluded from thermal desorption and electron impact desorption studies with Pt(111) that hydrogen adsorbs dissociatively at room temperature up to a coverage of about   (H a ) = 0.3 monolayer (ML). Lu and Rye [25] observed a single desorption maximum at 330 K in their thermal desorption experiments on Pt(111) after H 2 adsorption at 125 K. Exposing Pt(111) to a mixture of H 2 and D 2 showed complete isotopic equilibration [23]. Christmann et al [22] reported that hydrogen adsorbed dissociatively on Pt (111) with a saturation coverage of 0.8 ML at 150 K. They observed the evolution of two desorption peaks in the thermal desorption spectra (TDS): a high temperature state ( 2 ) and a low temperature state ( 1 ).…”