Chemical Forums

Specialty Chemistry Forums => Materials and Nanochemistry forum => Topic started by: aivar6 on October 14, 2014, 10:10:12 AM

Title: Hydrogen splitting in fuel cells
Post by: aivar6 on October 14, 2014, 10:10:12 AM

Why platinum splits the hydrogen atoms into a proton (H+) and electron (e-) in fuel cell? What is the reaction behind that and how platinum maintains its structure?

Title: Re: Hydrogen splitting in fuel cells
Post by: Borek on October 14, 2014, 04:49:02 PM

Platinum doesn't split them. The reaction is that of hydrogen (H₂) oxidation to H⁺. It happens that platinum electrode is the best for the process.

Title: Re: Hydrogen splitting in fuel cells
Post by: aivar6 on October 15, 2014, 03:01:56 AM

But why this oxidation happens and why platinum electrode is the best for that process? I know the reactions of electrolysis and fuel cells but there is never shown the role of platinum in that.

Title: Re: Hydrogen splitting in fuel cells
Post by: billnotgatez on October 15, 2014, 03:07:09 AM

Does this link help?

http://www.technology.matthey.com/article/57/4/259-271/

The Role of Platinum in Proton Exchange Membrane Fuel Cells
Evaluation of platinum's unique properties for use in both the anode and cathode of a proton exchange membrane fuel cell  By Oliver T. Holton  and Joseph W. Stevens

Title: Re: Hydrogen splitting in fuel cells
Post by: Enthalpy on October 15, 2014, 03:17:05 PM

I'm not quite convinced that one can tell whether adsorbed hydrogen is an atom or an ion. There are so many electrons nearby in the metal that telling if one electron pertains to the hydrogen or not must be quite subtle.

The important part is that hydrogen leaves this electrode as a positive charge, and this is possible because the electrolyte, thanks to its polar nature, dissolves the proton.