Schiff base as n-type semiconductor: synthesis, characterization, and diode features

A pyrene-based Schiff base, PyFA, with D-π-A structure was synthesized and the chemical structure was established using IR, NMR, and mass spectrometry. The photoluminescence studies revealed intramolecular charge transfer in PyFA with green fluorescence emission. PyFA with pyrene and fluorene as molecular units was thermally stable up to 300 °C and exhibited an electrochemical band gap of 3.5 eV. The thin films of PyFA exhibited higher carrier concentration, n-type semiconducting property, and a dielectric constant of 6.69. The thin films of PyFA displayed uniform and homogenous surface morphology, which is desirable for device application. A p-n type diode was constructed using PyFA and the diode parameters were extracted from the DC and AC measurements.