Empa researchers developing sustainable sensors and displays

July 07, 2023

Dübendorf - Researchers from the Swiss Federal Laboratories for Materials Science and Technology (Empa) have developed a biodegradable material that is capable of changing color and conducting electricity, while also being suited to 3D printing processes. This could facilitate the production of sustainable sensors and displays.

Empa researchers developing sustainable sensors and displays

Researchers from the Cellulose & Wood Materials lab at the Swiss Federal Laboratories for Materials Science and Technology (Empa) have developed a biodegradable material that changes color under the influence of heat, conducts electricity and can be 3D printed. The new material is made from hydroxypropyl cellulose (HPC), to which minute quantities of carbon nanotubes and cellulose nanofibers are added, further details of which can be found in a press release issued by Empa. The carbon nanotubes are responsible for the conductivity of the material, while the cellulose nanofibers make the material suitable for 3D printing.

In turn, HPC enables the coloring of the material. This form of cellulose forms colorless liquid crystals when mixed with water. These reflect different wavelengths of light depending on the temperature. In the project, the researchers used the new material to create various application examples, such as a strain sensor and display made from electrically conductive segments.

This is the first time we were able to develop a cellulose-based display.

Xavier Aeby - Empa, Co-author of the study

“Our lab has already developed different disposable electronic components based on cellulose, such as batteries and sensors”, comments Empa researchers Xavier Aeby in the press release. “This is the first time we were able to develop a cellulose-based display”, he adds. In the estimation of the researchers, the new material harbors massive potential. “Sustainable materials that can be 3D printed are of great interest, especially for applications in biodegradable electronics and the Internet of Things”, concludes Gustav Nyström, who heads up the laboratory. ce/hs