Capacitive Humidity Sensing using Carbon Nanotube Enabled Capillary Condensation

This electronic document is a "live" A capacitive humidity sensor, fabricated by depositing multi-wall carbon nanotubes (MWCNTs) on one of the stainless steel substrates, is presented for moisture detection at room temperature. When compared to a sensor without CNTs, CNT-enhanced sensor has a capacitance response of 60-200% more when the humidity is under 70% relative humidity (RH), and 300%-3000% more if RH level goes over 70%. The detection and recovery response times are on the order of seconds. The performance is comparable to a commercial sensor from Honeywell that is used as a benchmark throughout the experiments. Our results demonstrate that nano-materials like MWCNTs, can naturally form porous nano-structures, which can potentially realize a miniature capacitive humidity sensor with a higher sensing resolution. The gain in performance is attributed to capillary condensation effect. The capillary condensation effect, that is facilitated by the porous nanostructures of random aligned MWCNTs, is discussed in this paper template. The various components of your paper [title, text, heads, etc.] are already defined on the style sheet, as illustrated by the portions given in this document.

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