Synthesis of high-quality CdS nanowires and their application as humidity sensors

• High quality CdS nanowires (NWs) were synthesized.
• CdS NW humidity sensors were fabricated and studied.
• The sensor has a large resistance variation of ~2 orders of magnitude in the RH range of 30–90%.
• The sensor shows a high sensitivity of 47.5, a fast response time of 1.27 s, recovery time of 2.44 s and high stability to humidity variation.

High-quality CdS nanowires (NWs) were synthesized via the chemical vapor deposition (CVD) method in a Cd-enriched atmosphere. Humidity sensing characteristics of CdS NWs have been investigated. It was found that the resistance of the NWs decreases with increasing relative humidity (RH). At room temperature (RT), a large resistance variation of ~2 orders of magnitude in the RH range of 30–90% reveals CdS NW has high humidity sensitivity. CdS NWs humidity sensor shows a high sensitivity of 47.5, a fast response time of 1.27 s, recovery time of 2.44 s and high stability to humidity variation. These results indicate that the CdS NWs can serve as high-performance humidity sensors.