Development of novel complementary metal-oxide semiconductor-based colorimetric sensors for rapid detection of industrially important gases

A sensitive and low-cost colorimetric sensor array was developed to detect industrially important gases. We selected several target gases and indicators, and then used a printing method to fabricate an array to read the color value and to analyze the data. Using the printing method, various indicators can be produced in a uniform array on a desired substrate in a short time and at a low-cost. Four gases (ammonia, methylamine, trimethylamine, and hydrazine) and ten indicators were used to confirm the ability of the gas detection system. The color change of the dyes in the array was extracted in real time using an array reader with an integrated complementary metal-oxide semiconductor (CMOS) image sensor. The developed gas detection system successfully detected gases using an array reader, which provided data for sensitive color changes in real time using the CMOS image sensor. This mechanism could be applied industrially for detecting toxic gases because the developed sensor is highly sensitive and inexpensive.