Studies on humidity sensing properties of ammonium heptamolybdate tetrahydrate (NH4)6[Mo7O24] · 4H2O

✍ Scribed by S.A. Hashmi

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 407 KB
• Volume: 96
• Category: Article
• ISSN: 0167-2738
• DOI: 10.1016/s0167-2738(96)00568-1

✦ Synopsis

The material Ammonium heptamolybdate tetrahydrate has been shown to be an ionic conductor with r,<,,, -0.97. Its conductivity is strongly humidity dependent dominated by surface ion transport. This effect has been utilized to develop a humidity sensor. A linear change of -2000 times in the resistance of the sensor with 'finger-type' electrodes has been observed when relative humidity changes from 10% to 95%. The response time has been found to be -2 min when humidity changes from low to high R.H. values. The results have also been compared with a conventional disc-type sensor having electrodes deposited on both sides.