A good quality single crystal of Propyl triphenylphosphonium bromide (PTPB) was grown using a low-temperature solution technique with an aqueous solution at room temperature. The as-grown single crystal belongs to the monoclinic system with space group P21/c, as confirmed by single crystal X-ray diffraction. FT-IR spectral analysis confirmed the presence of various functional groups in the grown crystal. Additionally, optical characteristics were evaluated using UV-visible analysis. The lower cut-off wavelength observed in the spectrum was 312 nm, with an optical bandgap of 4 eV. The Urbach energy of the grown crystal was found to be minimal, indicating good crystallinity. Furthermore, the electron-phonon interaction energy was also estimated.