Researchers at the Shanghai Institute of Ceramics, Chinese Academy of Sciences, designed a “fire alarm wallpaper”, made of environmentally friendly, non-flammable materials, including the wonder material graphene and a component of bone. When exposed to heat, the wallpaper is transformed from an electrically insulating material into an electrically conductive one, causing it to automatically trigger an alarm.

Most common wallpapers are made of flammable materials, such as wood cellulose or plastic, which cause fire to spread rapidly.

The new fire alarm wallpaper is based on a material called hydroxyapatite, which is a component of bone and teeth. While the material is usually brittle, the researchers found that nanowires made of it are actually flexible.

The researchers applied a thermosensitive sensor behind the wallpaper, which is covered in an ink containing graphene oxide. The graphene oxide is electrically insulating at room temperature. However, when exposed to heat, the oxygen-containing groups are removed, making the material highly conductive. The sensor is connected to the alarm, and when it begins to conduct, the alarm goes off after two seconds.

The fire-resistant wallpaper has a white colour, and it can be processed into various shapes, dyed with different colours, and printed with a commercial printer.

The next step in the research is to scale up the production of hydroxyapatite nanowires to be able to mass-produce the fire alarm wallpaper. They are also looking into other uses of the paper, such as preservation of important paper documents, air purification, anti-counterfeiting, biomedical uses, and many more.