Redukcija kiseonika na monokristalnim platinskim elektrodama u rastvorima fosforne kiseline

Oxygen reduction reaction has been studied on Pt low index planes in 0.1 M and 85% H3PO4 using hanging meniscus rotating disc electrode technique. The first-order kinetics of O2 reduction reaction was found for all three surfaces in a four-electron process with the first electron transfer rate determining in both 0.1 M and 85% H2PO4 solutions. Catalytic activity for O2 reduction follows the sequence Pt (110)>Pt (100)>Pt (111). Structural dependence is predominantly determined by the adsorption of phosphoric acid anions, which is strongly structure-dependent on Pt surfaces.Ispitivana je reakcija redukcije kiseonika na niskoindeksnim monokristalima platine u 85%i0.1 M rastvoru H3PO4 tehnikom rotirajućeg meniska. Utvrđeno je da je u oba rastvora reakcija prvog reda i da se odigrava 4-elektronskim putem u kome je prenos prvog elektrona spori stupanj. Katalitička aktivnost za redukciju kiseonika sledi niz Pt(110) > Pt(100) > Pt(111). Strukturna zavisnost aktivnosti dominantno je određena strukturno zavisnom adsorpcijom anjona fosforne kiseline na Pt(hkl) ravnima