Raman spectroscopic and quantum chemical study of hydrogen adsorption at platinum electrodes

✍ Scribed by Xu, X.; Ren, B.; Wu, D. Y.; Xian, H.; Lu, X.; Shi, P.; Tian, Z. Q.

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 95 KB
• Volume: 28
• Category: Article
• ISSN: 0142-2421
• DOI: 10.1002/(sici)1096-9918(199908)28:1<111::aid-sia629>3.0.co;2-u

✦ Synopsis

Hydrogen adsorption at platinum electrodes in acidic solution is investigated by confocal microprobe Raman spectroscopy and quantum chemistry calculation. Vibration for on-top adsorbed hydrogen against a platinum surface is observed in the potential region of hydrogen evolution. With the negative moving of the potential, there is a red shift of Pt-H vibrational frequency. No Pt-H band could be detected in the strongly bound hydrogen adsorption region. A very weak and broad band for the terminal Pt-H vibration in the weakly bound hydrogen adsorption region is discernible when the underpotential deposition hydrogens are saturated. Ab initio cluster model calculations indicate that the large tuning rate of the Pt-H frequency should be attributed to the work function shift with the change of electrode potential. The calculation results show that the spectroscopic properties of the Pt-H bond are sensitive to the surface coverage. The experimentally observed red shift of Pt-H frequency with a decrease of electrode potential would originate from the lateral interaction of Pt-H bonds.