Going green with graphene

Here, Francesco Bonaccorso, deputy head of innovation of the Graphene Flagship, explains how its researchers have created a series of initiatives in order to take graphene from the laboratory to the commercial market.

Since it was first isolated in 2004, graphene has become a hot research topic. Graphene has been embraced across a variety of industries, most notably healthcare and material applications. And, now, graphene technology is being applied to renewable energy.

The graphene solar farm

According to a 2019 report by the Financial Times, it is forecast that coal, oil and gas will still contribute about 85% of the world’s primary energy supply by 2040, compared with 90% today. While these figures underline the need to reduce the levels of dependence on non-renewable sources, another report stated that the global supplies of renewable electricity could expand by 50% in the next five years – powered by a resurgence in solar energy.

Among the Graphene Flagship's spearhead projects, a series of initiatives undertaken with partners, is its Solar Farm initiative. The project created the world's first graphene-enabled solar farm in Crete, Greece. Led by its partner, the University of Rome Tor Vergata, a public research university in Rome, Italy, the project explores the production of graphene-enabled solar cells that could help bolster the European Union’s efforts to reduce dependence on fossil fuels.

In fact, the Solar Farm project has already seen great sustainability progress in developing its solar modules. This involves the production of large area graphene perovskite solar cells; single photovoltaic panels assembled from connected solar cells that are designed to increase the efficiency, and lower the cost, of solar energy. Researchers have already achieved power conversion efficiencies of 15.3% with the technology, which is a remarkable result.

Going forward, the project aims to surpass this figure and pave the way towards the future exploitation of graphene-basedperovskite solar cells. In tandem configuration with silicon-based solar cells, it is foreseen to achieve power conversion efficiencies beyond present records.

Batteries for a better world

Reducing our reliance on non-renewable sources is one thing, but what about sustainable developments in energy storage? According to the Consortium for Battery Innovation (CBI), worldwide demand for battery energy storage will significantly increase in 2025, and graphene and related materials could play a vital role in meeting that rise.

With this in mind, another of the Graphene Flagship’s energy spearhead projects, entitled Technology of Silicon Graphene Lithium-ion Batteries for Large Scale Production, aims to increase the electrode quality of lithium-ion batteries. The project has advanced the integration of silicon-graphene composites into lithium-ion batteries for high-energy and high-power applications.

Due to its high surface area, large electrical conductivity, lightweight characteristics, chemical stability and high mechanical flexibility, graphene can increase the energy capacity, charge rate and stability of lithium-ion batteries. In practicality, the lifespan and recharging time of batteries used in electronic applications — ranging from electric vehicles and mobile phones to laptops — could significantly improve.

Innovative projects like these can open the door to new areas of research and product design. To this end, the production of silicon-graphene lithium-ion batteries, coupled with the world’s first graphene-enabled farm, are just a few of the sustainability-focused projects that the Graphene Flagship is working on.

While it remains to be seen how graphene can transform the energy industry, its journey has only just begun in creating new opportunities for applications in energy storage and energy conversion. It seems likely that graphene and related materials could be exactly what is needed to help engineers find greener renewable alternatives to traditional materials to develop next-generation energy devices.