The electronic structure of polyaniline and doped phases studied by soft X-ray absorption and emission spectroscopies

TL;DR

This study investigates the electronic structure of polyaniline and its doped phases using advanced X-ray spectroscopic techniques, revealing how protonation alters the material's electronic properties.

Contribution

It provides new insights into the electronic changes in polyaniline upon doping, using resonant and nonresonant X-ray emission spectroscopy for detailed analysis.

Findings

Depletion of π electron bands observed upon excitation.

Electronic structure changes detected with protonation.

Chemical bonding characterized through combined spectroscopy.

Abstract

The electronic structure of the conjugated polymer, polyaniline, has been studied by resonant and nonresonant X-ray emission spectroscopy using synchrotron radiation for the excitation. The measurements were made on polyaniline and a few doped (protonated) phases for both the carbon and nitrogen contents. The resonant X-ray emission spectra show depletion of the {\pi} electron bands due to the selective excitation which enhances the effect of symmetry selection rules. The valence band structures in the X-ray emission spectra attributed to the {\pi} bands show unambiguous changes of the electronic structure upon protonation. By comparing to X-ray absorption measurements, the chemical bonding and electronic configuration is characterized.