Development of n-alkylammonium terephthalate immobilized sheet for facile measurement of spatial distribution of gaseous OH radical (OH)

Abstract

Abstract n-Alkylammonium terephthalate immobilized sheets enable the facile measurement of gaseous OH radical (OH). In this study, we have clarified the preparation conditions of the sheets to further improve the detection performance of OH. The fluorescence response to OH tended to increase with shorter alkyl chain lengths of the n-alkylamines, with bis(n-octylammonium) terephthalate (nOA-TA), an organic salt with an alkyl chain length of 8, exhibiting the best response performance. Furthermore, the smaller the pore size of the membrane filter immobilizing nOA-TA, the better the fluorescence response performance to OH. Finally, we developed a procedure for converting the fluorescence image of the nOA-TA immobilized sheet exposed to gaseous OH into an HTA/TA ratio map. This makes it possible to quantitatively visualize the spatial distribution of gaseous OH two-dimensionally.