Where the
world gathers for metal finishing
Q&As since 1989


-----

Depositing Nickel on Carbon Felt and Carbon Cloth

2007

Hi
I wanna deposit about 2 microns of thickness nickel on Carbon Felt and Carbon Cloth for the purpose of Electrodes ( electrodes are Carbon with catalyst Nickel on it for Fuel Cell).

Does anyone has any recipe or process for making the Electroless Bath for it? what reducing agent is the best to use .

Sarah Rezaei
student - Toronto, ON, Canada

---

A web search shows a number of patents and papers on the subject, Sarah. But the thing that may not be obvious is that you don't need to re-invent the science of electroless nickel plating as the first step of your project. You can buy robust plating processes from suppliers who have developed them over decades; you don't need to duplicate those decades of research and formulate them yourself. Some of those papers indicate that hypophosphite was used as the reducing agent, and this is the most common type of commercially available bath. Good luck.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2007

---

A plating process maybe isn't suitable if the carbon felt is very porous. It may end up saturated with liquid which will erupt through the plating under pressure or vacuum or when heated.

Look for a CVD or PVD process. Nickel carbonyl gas (poisonous) decomposes at 150-200 °C. Inco creates a nickel foam product by decomposing nickel carbonyl onto polyurethane foam under IR lamps, after which the polyurethane is burned out.
http://www.metalfoam.net/papers/paserin2004.pdf

PVD processes (e.g., evaporation in vacuum) may be suitable.

Ken Vlach [deceased]
- Goleta, California
Finishing.com honored Ken for his countless carefully researched responses. He passed away May 14, 2015.
Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2007

---

2007

Sarah
You have two basic problems
1/ Electroplating onto a porous felt will deposit on the surface but the plating thickness will decrease rapidly as you get inside the felt. To go this route it might be necessary to plate the carbon fibers and form the felt as a second stage.
2/ Electroless nickel may be persuaded to plate evenly throughout the mass but your application as a catalyst in a fuel cell may depend on the purity of the nickel.
Electroless nickel is not pure nickel. It is (usually) an alloy of say 5-15% phosphorus and may have a totally different electrode potential to pure nickel.

This is not a unique application, many researchers are working on fuel cells. I suggest that you contact nickel suppliers and ask if they can supply nickel felt.

Geoff Smith
Hampshire, England