The effect of electrochemical deposition solution’s pH on prepared platinumelectrocatalystcharecteristic for oxygen reduction reaction in low temperaturefuel cell systems

Nowadays, the fuel cell role in energy resources has been explicated more. At these systems,many activities are focused on improving sluggish oxygen reduction reaction at cathodeespecially in low temperature systems. Platinum is common electrocatalyst has been used in lowtemperature fuel cell systems for oxygen reduction reaction (ORR). Various methods have beenused for preparing platinum electrocatalyst at cathode. One of these methods is electrochemicaldeposition method. The platinum is electrodeposited from electrochemical deposition solution. Inthis process, various parameters have effect on performance of prepared electrocatalyst. In thiswork the pH of electrochemical deposition solution effect on properties of electrodepositedplatinum for ORR was studied. The pH of electrochemical deposition solution in presence ofBritton-Robinson Buffer(0/04 M H3PO4 H3BO4; CH3COOH +Xmm 0/2M NaOH) is variedfrom 8 to 11. For doing electrochemical electrodeposition cyclic voltammetry method(scan rate100 and potantioal -0.25 -1.25 (was used in a conventional three electrodesystem.Theelectrochemical methods like as linear sweep voltammetry and cyclic voltammetry were used forstudying the fabricated electrodes for ORR at sulfuric acid solution (2.5 M) saturated withoxygen gas. According our results, the pH of electrochemical deposition solution affects oncharacteristic of electrodeposited platinum as electrocatalyst for oxygen reduction reaction. It hasbeen shown the optimum result is related to buffer solution with pH 9.

کلیدواژه ها:

low temperature fuel cell ، oxygen reduction reaction ، platinum electrocatalyst ، electrodeposition ، Britton-Robinson Buffer