The feeling of new applications

Graphene is a one-atom-thick layer of carbon atoms. This provides a unique sensitivity to changes in the environment, which the Sensors Work Package studies to develop high-performance sensors with a variety of applications, from detecting infectious diseases, to piezoresistive devices for microphones and speakers.

In our work package, we investigate and develop sensors that exploit the unique properties of graphene and layered materials, such as sensitivity, conductivity and tuneability. For example, we used platinum diselenide to create a multifunctional sensor, which switches between the detection of toxic gases like ammonia and the detection of infrared radiation. This hybrid device suggests how different combinations of layered materials, as well as different topologies and structures, will lead to miniaturised devices for the sensing of chemicals and light.

This year’s progress

Amidst the COVID-19 pandemic, the Sensors Work Package steered the research efforts to focus on new graphene-enabled sensors for biomedical applications. We envisioned functionalisation methods to anchor graphene to proteins and antibodies, specific to different pathogens and diseases. Some of these devices target the coronavirus’ spike protein, offering solutions that yield effective, quantitative, quick results, without the need for hazardous reagents in the process. Our first prototypes detect the spike protein from saliva in only one step, offering results in a matter of minutes.

Our work package is deeply committed to sustainability. Amongst other applications, graphene-enabled sensors excel at the detection of carbon dioxide, one of the greenhouse gases that more heavily contributes to the current climate crisis. By creating heterostructures – sandwiches – of graphene and other layered materials, Graphene Flagship researchers have developed detectors for carbon dioxide, more compact and efficient than current solutions. Beyond environmental applications, CO2 detectors could also become an effective tool to tackle the pandemic. Good carbon dioxide detectors help monitor air quality, promoting proper ventilation procedures, therefore reducing transmission rates for coronavirus and other diseases.

Graphene also allows for ultimate force sensitivities in high-performance pressure sensors, microphones and accelerometers. In 2021, we created graphene-enabled microphones using transferless graphene, a material directly grown onto the desired substrates. We work to integrate all these devices on traditional CMOS silicon technologies, thus ensuring compatibility with state-of-the-art electronics and low-cost readout devices.

Upcoming challenges

Our main challenge in the Sensors Work Package is achieving full integration with CMOS devices. This means ensuring that graphene-enabled sensors transfer their readings successfully to traditional electronic devices, maximising the performance and the marketability of products. Graphene and layered materials have the potential to miniaturise all sorts of sensors, ready for applications in mobile phones, wearables and the Internet of Things, providing valuable information about everyday situations.