22 May 2019
Cheaper fuel cells thanks to platinum-nickel nanoframes
Published online 16 April 2014
Generation of electricity in fuel cells requires the transfer of electrons between the reactants and the electrodes, which can be facilitated by electrocatalysts. Platinum is an ideal material for making these electrocatalysts, but its rarity and expense are limiting the development of fuel cells in consumer goods.
A team of researchers, including Peiodong Yang of the King Abdulaziz University in Saudi Arabia, have designed a highly active and durable class of electrocatalysts by manipulating the structure of platinum-nickel crystals on the nanoscale, publishing their design in Science.
They synthesized platinum-nickel polyhedral crystals, and eroded the interior of the crystals to form platinum-nickel nanoframes, creating a hollow structure with a large surface area. This exposed more platinum atoms, which were previously buried under the surface where they are inaccessible, and means less platinum is needed to make the fuel cells.
The platinum-nickel nanoframe showed increased activity in catalyzing the oxygen reduction reaction, which is dependent on electron transfer to oxygen to reduce it to water, by 22-fold compared to pure metallic platinum per unit mass. The nanoframes were also more durable throughout electrochemical processes, making them favourable candidates for electrocatalyst development.
- Chen, C. et al. Highly Crystalline Multimetallic Nanoframes with Three-Dimensional Electrocatalytic Surfaces. Science (2014) doi:10.1126/science.1249061