Inkjet-printed gas sensors: Metal decorated WO ₃ nanoparticles and their gas sensing properties

Inkjet deposition is an attractive technology to localize nanomaterials in an area-selective manner on virtually any kind of surfaces. Great advantages of the method are effective usage of materials, low processing temperatures and few required manufacturing steps, thus enabling rapid prototyping and bulk production with reasonably low cost. A number of different electrical devices such as light emitting diodes, transistors and solar cells have already been demonstrated, reflecting the versatility of inkjet printing. In this paper, we collect the contemporary results on inkjet deposited gas sensors and show examples of such gas sensing devices based on surface modified WO ₃ nanoparticles for efficient discrimination of various gaseous analytes from sub-ppm up to nearly 0.1% concentration levels in air.