Enhancing hydrogen peroxide production in fuel cells
Hydrogen peroxide, like hydrogen, stores chemical energy and, upon decomposition into water and oxygen, it releases heat. However, hydrogen peroxide production through the anthraquinone process requires large and expensive installations and transport costs, making its use uneconomical. To address this issue and make hydrogen peroxide available on site and on demand, the EU-funded project ‘Nanostructures for energy and chemicals production’ (NENA) optimised the production of hydrogen peroxide in fuel cells. Among the project objectives was the development of a theoretical and computational chemistry for the design of nanoscale electrocatalytic materials and the production of hydrogen peroxide and epoxides in a fuel cell using nanoparticles of different materials. Firstly, scientists investigated a mechanism for lowering the energy of activation of the hydrogen oxidation reaction. According to this model the platinum group metals were considered to be good catalysts, due to their high electrochemical potential – also referred to as the Fermi level – and for the same reason nickel and cobalt were bad catalysts. Following investigation into the mechanism of oxygen reduction and the use of various oxides and metals as electrocatalysts, hydrogen peroxide production from a single cell reached 8 % concentration, much higher than ever reported before. The NENA project demonstrated the feasibility of producing hydrogen peroxide by the electrochemical reaction of oxygen and hydrogen in a fuel cell, a technique that could be industrially implemented in the next few years. The new process could significantly reduce the cost of producing hydrogen peroxide and provide an opportunity to generate it locally with renewable resources. Furthermore, the project deliverables are expected to open up the possibility of a new approach to industrial production of chemicals, the synthesis of which involves changes in oxidation state.
