The potential for graphene to positively impact the world continues to expand, with researchers reporting that they now understand why graphene is permeable to protons. This development, they say, could accelerate the development of the hydrogen economy.
Reporting their work in the journal Nature, researchers from the UK’s University of Manchester and University of Warwick used scanning electrochemical cell microscopy to measure proton currents collected from nanometre-sized areas of graphene. This allowed the team to visualise the spatial distribution of proton currents through graphene membranes.
They found that not only are perfect graphene crystals permeable to protons, they are also accelerated around nanoscale wrinkles and ripples in the crystal. ‘Our results provide microscopic proof that graphene is intrinsically permeable to protons,’ said Drs Segun Wahab, Department of Chemistry, University of Warwick, and Enrico Daviddi, Research Fellow in the Warwick Electrochemistry and Interfaces Group, lead authors of the paper.
As well as solving the puzzle of why graphene is much more permeable to protons than theory would suggest, it also opens the door to developing new hydrogen-based technologies. ‘Exploiting the catalytic activity of ripples and wrinkles in 2D crystals is a fundamentally new way to accelerate ion transport and chemical reactions. This could lead to the development of low-cost catalysts for hydrogen related technologies,’ said Dr Marcelo Lozada-Hidalgo, Department of Physics and Astronomy University of Manchester, National Graphene Institute University of Manchester.
Expensive catalysts and membranes that are currently used to generate and make use of hydrogen could be replaced with more sustainable 2D crystals, reducing carbon emissions and contributing to net-zero through the generation of green hydrogen, the researchers added.
The potential for graphene is being investigated in a range of areas. In 2021, a stretch of road in the UK became the first in the world to be resurfaced with a material containing graphene. The trial focused on investigating if the presence of graphene prolonged the life of the road surface.
In 2018, researchers at the University of Manchester reported the development of an ultra-thin graphene oxide membrane having a positive impact on modern membrane desalination and water filtration techniques.
And looking to produce graphene from renewable sources, a project called Grow Graphene received UK government funding to progress its research. The project seeks to use crops, such as flax, as a production feedstock, and capture carbon at the same time.