【摘要】 本文讨论了不同的预处理对Pt电极pH响应的影响。经阴极极化或火焰上红热后,Pt电极以 Pt（OH）₂+2e?Pt+2OH^-响应溶液的pH。而经+1.5V（vs.SCE）阳极极化后,由于Pt电极表面PtO₂的快速分解,电极的电位值很快下降,并逐渐达到稳定值,稳定后的Pt电极仍以上式响应溶液的pH。用KMnO₄溶液浸泡后,Pt电极表面有MnO₂沉积,并以 MnO₂+4H⁺+2e?Mn²⁺+2H₂O（pH 2-7） 2MnO₂+2H⁺+2e?Mn₂O₃+H₂O（pH 8-12）响应溶液的pH。更多还原

【Abstract】 The effect of different pretreatment on pH response of Pt electrode was studied. Forcathodized or ignited Pt electrode, the following equation is given for the electrodeprocess Pt（OH）₂+2e=Pt+2OH^-or PtO+2H⁺+2e=Pt+H₂OAfter anodized in 0.1 M H₂SO₄ at 1.5 V vs. SOE, Pt electrode is partially covered withPtO₂. Under open circuit condition, PtO₂ decomposes to PtO in the presence of Pt.Elec-trode potential decreases rapidly and reaches gradually the stable value. The stabilizedPt electrode also responds to pH according to the above -mentioned equation. After soaked in permanganate solution, Pt electrode is covered with MnO₂. Thepotential vs. pH behaviour is close to that predicted for the reactions. MnO₂+4H⁺+2e=Mn²⁺+2H₂O （pH 2--7）or MnO₂+2H⁺+2e=Mn₂O₃+H₂O （pH 8--12）更多还原