New High-Performance Catalyst for Hydrogen Production Is a Step Low Cost Hydrogen Fuel

The new findings were published in ChemSusChem, a top journal covering sustainable chemistry and energy materials, and the paper is featured on the cover of the January 10 issue. First author Yi Peng, a graduate student in Chen’s lab, led the study and designed the cover image.

Hydrogen has long been attractive as a clean and renewable fuel. A hydrogen fuel cell powering an electric vehicle, for example, emits only water vapor. Currently, however, hydrogen production still depends heavily on fossil fuels (mostly using steam to extract it from natural gas). Finding a low-cost, efficient way to extract hydrogen from water through electrolysis would be a major breakthrough. Electricity from renewable sources such as solar and wind power, which can be intermittent and unreliable, could then be easily stored and distributed as hydrogen fuel.

Currently, the most efficient catalysts for the electrochemical reaction that generates hydrogen from water are based on platinum, which is scarce and expensive. Carbon-based materials have shown promise, but their performance has not come close to that of platinum-based catalysts.

In the new composite material developed by Chen’s lab, the ruthenium ions embedded in the carbon nitride nanosheets change the distribution of electrons in the matrix, creating more active sites for the binding of protons to generate hydrogen. Adding graphene to the structure further enhances the redistribution of electrons.

“The graphene forms a sandwich structure with the carbon nitride nanosheets and results in further redistribution of electrons. This gives us greater proton reduction efficiencies,” Chen said.

The electrocatalytic performance of the composite was comparable to that of commercial platinum catalysts, the authors reported. Chen noted, however, that researchers still have a long way to go to achieve cheap and efficient hydrogen production.

In addition to Peng and Chen, coauthors of the study include Wanzhang Pan and Jia-En Liu at UC Santa Cruz and Nan Wang at South China University of Technology. This work was supported by the National Science Foundation and the NASA-funded Merced Nanomaterials Center for Energy and Sensing.

Contacts and sources:
Tim Stephens
University of California Santa Cruz   (UC Santa Cruz)