کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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5423947 | 1395808 | 2009 | 7 صفحه PDF | دانلود رایگان |
High-resolution core-level photoemission and scanned-energy mode photoelectron diffraction (PhD) of the O 1s and N 1s states have been used to investigate the interaction of glycine with the rutile TiO2(1 1 0) surface. Whilst there is clear evidence for the presence of the zwitterion NH3+CH2COOâ with multilayer deposition, at low coverage only the deprotonated glycinate species, NH2CH2COO is present. Multiple-scattering simulations of the O 1s PhD data show the glycinate is bonded to the surface through the two carboxylate O atoms which occupy near-atop sites above the five-fold-coordinated surface Ti atoms, with a Ti-O bondlength of 2.12 ± 0.06 à . Atomic hydrogen arising from the deprotonation is coadsorbed to form hydroxyl species at the bridging oxygen sites with an associated Ti-O bondlength of 2.01 ± 0.03 à . Absence of any significant PhD modulations of the N 1s emission is consistent with the amino N atom not being involved in the surface bonding, unlike the case of glycinate on Cu(1 1 0) and Cu(1 0 0).
Journal: Surface Science - Volume 603, Issue 15, 1 August 2009, Pages 2305-2311