A study group of Anhui Institute of Optics and Fine Mechanics under Hefei Institutes of Physical Science have explored novel H₂S sensor with high selectivity of H₂S that is a toxic gas. This work was done by FANG Xiaodong and MENG Gang and their research team.

H₂S is one of highly toxic gases. Short-term inhalation of high concentration (~500 ppm) H₂S may cause death in a very short time. Even low concentration (~5-20 ppm) H₂S if long-term exposure is also harmful to eyes, respiratory system and central nerves. According to National Occupational Health Standards (GBZ 2.1-2007) of China, the occupational exposure limit (OELs) of H₂S in the workplace is 10 ppm.

The team reported an ultra-high electrical response of the CuAlO₂ sensor of from 4600 to 10 ppm H₂S and less than 2 to 100 ppm NH₃, NO₂ and various volatile organic compounds at 160℃, indicating an excellent selectivity.

In addition, the CuAlO₂ sensor also showed a fast response characteristic, once the concentration of H₂S in the environment was higher than 4 ppm, 3 orders increase of sensor resistance was accompanied within 1 minute, enabling a prompt alarm.

Besides H₂S, the researchers developed high sensitivity and selective ammonia sensor based on delafossite AgAlO₂ and CuScO₂.

These works were financially supported by the projects of International Cooperation and the National Natural Science Foundation of China, etc.

Link to the paper: A novel ammonia gas sensors based on p-type delafossite AgAlO₂

Insight into the Humidity Dependent Pseudo-n-Type Response of p-CuScO₂ toward Ammonia

Ultrasensitive and selective CuAlO₂ sensor toward H₂S based on surface sulfuration-desulfuration reaction

Contact:

ZHOU Shu

Hefei Institutes of Physical Science (http://english.hf.cas.cn/)

Email: zhous@hfcas.ac.cn