Novel Donor-Acceptor Based 4-Nitrophenol Luminophores as a Yellow-Orange Fluorescent Material for Optoelectronic Applications.

A new category of 4-nitrophenol (4-NP) luminophores, infused with varying amounts of Pyrene (Py), was synthesized using the standard solid-state reaction method to investigate novel luminophores that emit at longer wavelengths. Their optical and electrochemical properties were analyzed using fluorimetry and cyclic voltammetry techniques. The fluorescence spectrum of Py-doped 4-NP displayed a broad fluorescence band with a peak at 599 nm for a Py concentration of 1 × 10^- 3 mol, indicating exciplex formation between 4-NP and Py in the excited state. The electrochemical data revealed that the energy levels of the Highest Occupied Molecular Orbital (HOMO) and Lowest Unoccupied Molecular Orbital (LUMO) for the synthesized luminophores ranged from - 5.72 to -5.73 eV and - 3.01 to -3.08 eV, respectively. Thermal stability was evaluated through TGA analysis. The XRD confirmed the synthesis of a homogeneous material. The SEM images showed crystal sizes of approximately 115 nm. This thorough investigation indicates the potential of these newly synthesized yellow-orange fluorescent luminophores for optoelectronic applications.