Gas sensors using carbon nanomaterials: A review

Carbon nanomaterials have been attracting a great deal of research interest in the last few years. Their unique electrical, optical and mechanical properties make them very interesting for developing the new generation of miniaturised, low-power, ubiquitous sensors. In the particular case of gas sensing, some carbon nanomaterials such as nanofibres, nanotubes and graphene are threatening the dominance position of other well established (nano)materials, yet the commercial exploitation of carbon nanomaterials is still a way off. This paper reviews the state of the art for electrical gas sensors employing carbon nanomaterials, identifies the bottlenecks that impair their commercialisation and also some recent breakthroughs. Finally an outlook in which challenges and opportunities are identified is given.