Nano-WO3 film is the better optical gas sensor material.

WO3薄膜是良好的光学气敏传感器材料。

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As a material highly sensitive to the environment, graphene could act as a sensor with a single device measuring strain, gas, magnetism or pressure.

BBC: Is graphene really a wonder-material?

Any material that has even the tiniest bit of conductive capability can be a touch sensor with the Makey Makey.

FORBES: Makey Makey Hits $568,106 and 11,124 Consumers Said Yes

This microscopic scale and sensitivity allows the sensor to map a high-resolution image of electrical charge that occurs over the surface of a source material (for example a human finger), when it makes contact with a thin insulating surface (ie a plastic surface).

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