将磷钼酸(PMo12)修饰到电化学聚合制得的聚3,4-乙烯二氧噻吩(PEDOT)(PEDOT/GC)膜表面(PMo12/PEDOT/GC),随后电沉积Pt得Pt/PMo12/PEDOT/GC电极. 研究了PMo12和PEDOT对电极氧化甲醇性能的影响. 结果表明,PMo12改变了电极上负载Pt的形态和结构,导致Pt纳米结构边缘产生尖锐的刺状结构. Pt/PMo12/PEDOT/GC和Pt/PEDOT/GC电极有较好的甲醇氧化电催化活性,而前者尤佳. PEDOT不仅提高甲醇氧化的电流,还使甲醇的起始氧化电位负移. 进一步修饰PMo12后,可明显增大甲醇氧化的电流.
马静华
,
王睿翔
,
谭一良
,
王珊珊
,
张艳勤
,
樊友军
. Pt/PMo12/PEDOT/GC电极的制备及其甲醇电氧化性能[J]. 电化学, 2013
, 19(2)
: 164
-168
.
DOI: 10.61558/2993-074X.2109
Modification of phosphomolybdic acid (PMo12) on poly(3,4-ethylenedioxythiophene) (PEDOT) film (PEDOT/GC) obtained through the electrochemical polymerization was performed using adsorption method (PMo12/PEDOT/GC), followed by electrodepositing Pt on PMo12/PEDOT/GC to prepare Pt/PMo12/PEDOT/GC electrode. Effects of PMo12 and PEDOT on the methanol oxidation performance of electrode were investigated. Results showed that PMo12 obviously changed the morphology and structure of Pt loaded on the electrode, leading to the formation of sharp thorns at the edge of Pt nanostructures. Cyclic voltammetry and chronoamperometry data demonstrated that the catalytic activities of methanol electrooxidation on the Pt/PMo12/PEDOT/GC and Pt/PEDOT/GC electrodes were higher than that on Pt/C, and the former exhibited the best performance. It was found that the presence of PEDOT not only increased the current, but also lowered the onset potential towards methanol oxidation. After further modification of PMo12, the current of methanol oxidation was significantly increased, while the onset potential of methanol oxidation remained unaffected.
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