Graphene Nanocomposite for Reversible Hydrogen Storage

Authors: Piotr Kula, Lukasz Kaczmarek

Original technology for the fabrication of High-Strength Metallurgical Graphene HSMG® was developed and put into production. The method is based on the crystallization of monolayer quasi monocrystalline graphene on a liquid copper surface. The possibility of reversible hydrogen chemisorption by this nanomaterial was experimentally confirmed. An industrial prototype plant to produce of large-area flats of metallurgical graphene with a high throughput of up to 0.5m2/process was designed and put into operation.  High-Strength Metallurgical Graphene HSMG® was used as a model material for fundamental research on hydrogen sorption and desorption. Methods have been developed for the functionalization of graphene as well as decoration of it with “spill-over catalysts” towards the creation of nanoporous three-dimensional nanostructures suitable for industrially scaled graphene nanocomposites that reversibly sorb hydrogen.

The technology for the fabrication of nano-meso-micro structured graphene composite for reversible hydrogen storage was developed. The starting raw material for the industrial scale-up of this technology is reduced graphene oxide at the industrial exfoliation stage. The microstructure of the composite contains active graphene flakes spatially filamented with oxygen-nitrogen bridges and decorated with metallic ‘spill-over’ catalysts for molecular hydrogen dissociation reactions.

The laboratory experimental model of a low-pressure, pump-free hydrogen sorber and compressor was designed and fabricated to test the functionality and sorption capacity of the fabricated graphene materials. In addition, the PCT characteristics (pressure, concentration temperature) of the developed hydrogen reversibly sorbing nanocomposite were determined using an experimental setup. These data will enable the design and technology of low-pressure tanks for reverse hydrogen storage to be developed.

The application range of that nanomaterial is planned as the first in hydrogen recycling and hydrogen recovery systems which will be widely used in advanced facilities for low pressure heat treating and thermochemical treating processes. Low-pressure pumpless compressors with nanographene sorbent beds can also be used extensively in hydrogen green energy conversion systems, especially in harbors infrastructure facilities and other autonomic energy grids as flexible storage of renewable energy. Further improving of hydrogen absorption capacity, over the critical threshold 6,5% by wt., should extend the application range of new nano- mezzo graphene composite towards the hydrogen storage systems in “vehicles of the future”.

Additionally, the High-Strength Metallurgical Graphene HSMG®, developed as part of the project, could be a promising new functional material for many applications, including as a filtering membrane for reverse osmosis, an active element in industrial and biological sensors or as a flexible monolayer semiconductor.