Tuning of polydiacetylene phase behaviours and design of volatile organic compound (VOC) sensors

Volatile organic compounds (VOCs) are common indoor and outdoor air contaminants that can significantly contribute to air quality as well as human health issues. Monitoring VOC levels in indoor spaces is critical for public health. Existing sensing methods can necessitate expensive equipment or lengthy procedures. Here we demonstrated a novel PDA and paper based colorimetric sensor that can rapidly detect several VOCs investigated in this work . Our designed sensor provides a visible colour change from blue to red pattern characteristic of specific voes by utilizing the unique optical features of PDAs when exposed to VOC vapours. This technology accurately detects seven typical VOCs prevalent in everyday products- chlorobenzene, 1, 2-dichlorobenzene, T-butanol, pyridine, at volume ratio concentrations in ambient condition. Our designed sensor functions at room temperature, requires no maintenance, and consumes no electricity while in use. The sensor has been designed on nitrate cellulose membrane with the help of 10, 12-heptacosadiynoic acid (HeDA) and 4-methyl-7-octadecyloxy- 2H-chromen-2-one (SBC-208). In addition with these two chemicals, saponite clay has also been used as a host material for the stability of designed sensor. (author)