People require good air quality to work especially in small enclosed spaces. A KAUST team has developed electronic sensors that can monitor at least three critical parameters that are significant in the safety of humans. 

Fluorinated metal-organic frameworks (MOFs) serve as the sensing layer for these sensors. A regular array of metal atoms bonded by small organic-molecule linkers compose the porous MOFs. Team leader Mohamed Eddaoudi showed that changing the metal and organic components of MOFs can allow them to be used for various applications that range from catalysis, sensing, gas separation, and storage. 

"Many people have attempted to develop simple, efficient, low-cost SO2, CO2and H2O sensors without success," say researchers Mohamed Rachid Tchalala, Youssef Belmabkhout and Prashant Bhatt, all from Eddoudi's lab. 

The research was a collaboration among Eddadoudi's team who developed a fluorinated MOF, Belmabkhout, and Tchalala testing the sensors for these gases, as well as Khaleb Nabil Salama and his group for testing these materials. 

"The first study shows how the sensor can measure the concentration of carbon dioxide and the level of humidity in the air1. While the second study of the same fluorinated MOFs shows it can detect the harmful and corrosive gas sulfur dioxide, or even selectively remove it from powerplant flue gas," according to Science & Technology Research News.

"Traces of SO2 are invariably present in the flue gas produced by factories and powerplants, and SO2 can poison materials developed to trap CO2 for carbon capture and storage," say Belmabkhout and Bhatt. "AlFFIVE-1-Ni can soak up SO2 with an affinity 66 times higher than for CO2, while showing good stability to SO2 exposure."

Moisture and carbon dioxide levels could be monitored by these sensor platforms under real atmospheric conditions. 

"The signal is calibrated against CO2concentration, humidity level and mixtures of both," Tchalala explains. A QCM-based sensor could also detect SO2 in the air at levels of just 25 parts per million.