Synthesis and Characterization of Polyaniline Emeraldine Salt: Tunable Photoluminescence and Optoelectronic Properties for Advanced Applications

Muna A. Bin  Gawbah; Elfatih A.  Hassan; Faiz M.B.  Elshafia; Ali A.S.  Marouf

doi:10.6000/1929-5995.2025.14.09

Authors

Muna A. Bin Gawbah Department of Physics, Faculty of Applied and Industrial Sciences, Bahri University, Khartoum, Sudan and Physics Department, Faculty of Education, Seiyun University, Hadhramout, Yemen
Elfatih A. Hassan Department of Chemistry, College of Science, Sudan University of Science and Technology, Khartoum, Sudan
Faiz M.B. Elshafia Department of Physics, Faculty of Science, Al-Baha University, Saudi Arabia and Department of Physics, College of Science, Sudan University of Science and Technology, Khartoum, Sudan
Ali A.S. Marouf Department of Laser Industrial and Engineering Applications, Institute of Laser, Sudan University of Science and Technology, Khartoum, Sudan https://orcid.org/0000-0001-9794-1023

DOI:

https://doi.org/10.6000/1929-5995.2025.14.09

Keywords:

Functional, Nanostructure, Optoelectronic, Photoluminescence, Polymerization, Semiconducting

Abstract

Polyaniline emeraldine salt (PANI-ES) is a conductive polymer with promising optoelectronic properties, synthesized via chemical oxidative polymerization and confirmed in its emeraldine salt form through structural analysis. Optical characterization revealed distinct absorption bands linked to key electronic transitions, indicating semiconducting behavior. Under UV excitation, photoluminescence studies showed two main emission features corresponding to dimer and excimer states, both exhibiting large Stokes shifts and a quantum yield of 0.27. These long Stokes shifts suggest efficient energy relaxation, while the moderate quantum efficiency highlights the material’s capability for light-emitting applications. The combination of tunable emission, stable optical response, and electrical conductivity positions PANI-ES as a versatile material for photonic technologies. Potential applications include organic light-emitting diodes (OLEDs), photodetectors, and optically pumped organic lasers. Overall, the study demonstrates that PANI-ES offers a favorable balance of structural stability, optical performance, and electronic properties, making it a strong candidate for integration into advanced optoelectronic and photonic devices.

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