Platinum is a silvery-white metal that doesn’t oxidize in air at any temperature, making it one of the least reactive of the noble metals. Its also pretty malleable, so it can be shaped into whatever you want, which is why it’s used in a lot of jewelry. But what if that platinum ring you wear started turning black or discoloring? Would that mean it’s not platinum anymore? Or is it something else entirely?
The answer is actually not that far-fetched, as a platinum ring is likely made with a mix of durable metals like copper, nickel and zinc. It’s those other metals that start to oxidize in contact with air and water, which is what causes your precious metal to turn a bit tarnished over time.
platinum black is finely powdered platinum that has good catalytic properties and has a high surface area. It is often used to cover platinum electrodes for electrochemical reactions, such as proton exchange membrane fuel cells or thin film coatings. It can be used to improve adhesion of the catalyst to the cathode as well as its activity.
We synthesized platinum black on a copper cathode in aqueous (H2SO4) and non-aqueous (isopropanol) media using 0.1 g PtCl4 and 0.002 g Pb(CH3COO)2. The results showed that the platinum black layer on the electrodes was stable over time and exhibited high catalytic activity.
We found that the optimum loadings of platinum black and Nafion/S-PEEK electrode ionomers were