Influence of Hydrogen Bonding on the Photophysical Properties of Diethylamino Hydroxybenzoyl Hexyl Benzoate

Abstract

In this study, we investigated the effects of different hydrogen bond types on the photophysical properties of diethylamino hydroxybenzoyl hexyl benzoate (DHHB) by systematically exploring the changes in the spectral properties of DHHB in protic and aprotic solvents. The formation and stability of hydrogen bonds were also studied, demonstrating that the system mainly existed in the form of intramolecular hydrogen bonds at low concentrations (≤5 μg/mL). In these circumstances, the fluorescent intensity, and molar absorption coefficient changed little, indicating that the intramolecular hydrogen bonds had little effect on the spectral properties of DHHB. With an increase in concentration, the number of intermolecular hydrogen bonds increased and the molar absorption coefficient significantly increased, indicating that the intermolecular hydrogen bonds were conducive to improving the UV absorption properties of DHHB. With an increase in temperature, the molar absorption coefficient of the system decreased, which reduced the UV absorption performance of DHHB. In the protic solvent, the system also contained DHHB–solvent intermolecular hydrogen bonds. With an increase in the proportion of protic solvent in the system, the fluorescent intensity of the system significantly decreased, and the UV integral area significantly increased, indicating that the hydrogen bond between DHHB and the solvent molecules was beneficial in terms of improving the UV absorption performance of DHHB.