Facile synthesis of size-controlled Fe 2 O 3 nanoparticle-decorated carbon nanotubes for highly sensitive H 2 S detection.

Hydrogen sulfide (H 2 S) is one of the most plentiful toxic gases in a real-life and causes a collapse of the nervous system and a disturbance of the cellular respiration. Therefore, highly sensitive and selective H 2 S gas sensor systems are becoming increasingly important in environmental monitoring and safety. In this report, we suggest the facile synthesis method of the Fe 2 O 3 particles uniformly decorated on carbon nanotubes (Fe 2 O 3 @CNT) to detect H 2 S gas using oxidative co-polymerization (pyrrole and 3-carboxylated pyrrole) and heat treatment. The as prepared Fe 2 O 3 @CNT-based sensor electrode is highly sensitive (as low as 1 ppm), selective and stable to H 2 S gas at 25 °C, which shows promise for operating in medical diagnosis and environment monitoring. Excellent performance of the Fe 2 O 3 @CNT is due to the unique morphology of the nanocomposites made from uniformly dispersed Fe 2 O 3 nanoparticles on the carbon surface without aggregation.