A Fluorescent Optode Membrane Covalently Immobilized with a Donor–Acceptor Conjugated Dye for pH Sensing under Extremely Acidic Conditions

Abstract

Figure S1 SEM image of the optode membrane on the glass plate. Figure S2. Linear calibration curve for the absorbance ratio change from pH 0.0 to 2.0. Figure S3. 1H NMR spectrum of compound 2. Figure S4. 13C NMR spectrum of compound 2. Figure S5. Mass spectrum of compound 2. Figure S6. 1H NMR spectrum of compound 3. Figure S7. 13C NMR spectrum of compound 3. Figure S8. Mass spectrum of compound 3. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.