Merging interior design and safety, scientists in China have developed a fire-resistant wallpaper equipped with an alarm. Two types of nanomaterials were key to making the danger-detecting decor. Glass fibers wrapped with ultralong hydroxyapatite nanowires were woven into an inorganic, fire-resistant paper. This paper was then attached to a sensor made from polydopamine-modified graphene oxide that responds to high temperatures (ACS Nano 2018, DOI: 10.1021/acsnano.8b00047). The wallpaper was developed by researchers at the Shanghai Institute of Ceramics and the University of Chinese Academy of Sciences led by Ying-Jie Zhu. Although hydroxyapatite—a form of calcium phosphate found in teeth and bone—is typically brittle, it becomes flexible when fashioned into ultralong nanowires. Paper made from glass fibers wrapped with these hydroxyapatite nanowires is environmentally benign and can be colored with dyes or with a printer. An attached graphene oxide sensor that’s connected to an alarm and a warning light switches on when the high temperatures that accompany a fire convert graphene oxide from an insulator into a good conductor of electricity. Modifying the surface of graphene oxide with polydopamine helps accelerate this transition and helps the graphene oxide resist flames. Hydroxyapatite nanowire paper equipped with this type of sensor was able to sound an alarm for more than five minutes in a direct flame, demonstrating that the electronics remained intact.