Drawing Carbon Nanotube-Based Sensors on Paper
Carbon nanotubes offer a powerful new way to detect harmful gases in the environment. However, the methods typically used to build carbon nanotube sensors are hazardous and not suited for large-scale production. A new fabrication method created by MIT chemists may overcome that obstacle. MIT postdoc Katherine Mirica has designed a new type of pencil lead in which graphite is replaced with a compressed powder of carbon nanotubes. The lead, which can be used with a regular mechanical pencil, can inscribe sensors on any paper surface. The sensor detects minute amounts of ammonia gas, an industrial hazard, and could be adapted to detect nearly any type of gas.