Fig. 6
Function as formaldehyde and temperature detectors. a Formaldehyde detection by colorless D1-NH2NH2 fluorescence turn-on process. Fluorescence change of D1-NH2NH2 complex (EtOH solution, 10−4 M) upon gradually addition of formaldehyde in EtOH (0, 0.1, 0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 4.5, 5.0 μg/L; 0.1 μg/L = 3.34 × 10−9 mol/L, 0.1 ppb) at room temperature. Y = 435.0 × X + 181.8 (R2 = 0.9906). The spectra were measured 1 min after formaldehyde addition to minimize relative error, although negligible differentials could be detected between 10 sec. and 1 min. b Photographs of gradient colorimetric and fluorescence change of D1-NH2NH2 ethanol solution in quartz NMR tube with gradient temperature. 1, gradient temperature, no irradiation; 2, gradient temperature, 365 nm irradiation. c The CIE chromaticity diagram with temperature dependence of the (x, y) chromatic coordinates of D1-NH2NH2. d The fluorescence spectrum of D1-NH2NH2 (10−4 M) in EtOH solution. Excitation wavelength: 365 nm
