在铂上四氢呋喃电氧化的吸附中间物的研究

STUDY ON INTERMEDIATES FOR ELECTRO-OXIDATION OF TETRAHYDROFURAN ON PLATINUM ANODE

应用电位扫描和电位-时间程序技术,研究了四氢呋喃在铂电极上和在HClO_4溶液中电催化氧化时的吸附中间物.结果表明,在铂表面上存在三种独方形成的吸附中间物.论证了这些吸附中间物的可能构型及其形成机理。

Using potential sweep and potential-time sequence techniques, we have studiedthe adsorbed intermediates for the electrocatalytic oxidation of tetrahydrofuran onplatinum electrode in HClO_4 aqueous solution, in comparison with the analogouselectrochemical behaviours of n-butanol and 1, 4-butanediol. We arrived at thefollowing main conclusions: (1) Three different intermediates (P_1, P_2 and P_3) form indenendently fromtetrahydrofuran on the surface of platinum anode. (2) The surface hydrogen is neccessary for the formation of all the intermediates,and the free active site is also neccessary for the intermediate P_1. (3) Probably the 5-member ring of tetrahydrofuran is opened during the forma-tion of intermediates P_2 and P_3 but may not for the formation of P_1. (4) The intermediate P, is adsorbed on platinum surface by one site. Thus, we have proposed the possible configurations and mechanism of the forma-tion of adsorbed intermediates in the electrocatalytic oxidation of tetrahydrofuran onplatinum as shown in formulas (1)--(4).