THE ELECTROCHEMISTRY OF [PTH(PET3)3]+ - INVERTED AND AMPLIFIED CYCLIC VOLTAMMETRIC WAVES AND CATALYTIC HYDROGEN-PRODUCTION AT A MERCURY-ELECTRODE
Inverted and amplified waves in cyclic voltammograms of [PtH(PEt3)3]+ at a sitting mercury drop electrode are interpreted in terms of catalytic cycles for hydrogen production from water involving adsorbed species. The adsorption step on the cathodic sweep involves a two-electron reduction to the cat...
| Main Authors: | , |
|---|---|
| Format: | Journal article |
| Language: | English |
| Published: |
1986
|
| Summary: | Inverted and amplified waves in cyclic voltammograms of [PtH(PEt3)3]+ at a sitting mercury drop electrode are interpreted in terms of catalytic cycles for hydrogen production from water involving adsorbed species. The adsorption step on the cathodic sweep involves a two-electron reduction to the catalytically inactive species [PtH(PEt3)3]- (ads.). On the reverse (anodic) sweep, a reductive catalytic cycle is initiated by oxidation to [PtH(PEt3)3]. (ads.) and stops when the potential is insufficiently negative to reduce [Pt(PEt3)3].+ (ads.) {or [PtH2(PEt3)3].+ (ads.)}. In second and subsequent forward scans the catalytic cycle restarts when the potential is sufficiently reducing to reduce [Pt(PEt3)3].+ (ads.) or [PtH2(PEt3)3].+ (ads.) and terminates when [PtH(PEt3)3]. (ads.) is reduced to [PtH (PEt3)3]- (ads.). Variations in peak shape and position with [PtH(PEt3)3]+ (aq.) concentration are interpreted in terms of partial or full desorption of [Pt(PEt3)3] (ads.) or [PtH(PEt3)3]. (ads.) during the catalytic cyclic under certain conditions. Catalysis of hydrogen production at a mercury drop electrode with catalyst turnover numbers up to 2 × 105 h-1 for > 16 h is also described. |
|---|