N-PASS-W showed an ionic conductivity of 10 mS cm–1, indicating that aliovalent substitution significantly improves sodium ion conduction.
The activation energy for ionic conduction was found to be only 0.15 eV, suggesting a favorable transport mechanism in mixed-pnicogen solid solutions.
PXRD and NMR spectroscopy provided insights into the structure of N-PASS-W, where ion hopping occurs over multiple sodium sites in a tetragonal configuration.
The study establishes that site disorder and crystalline phase directly influence the ionic conductivities of sodium chalcogenides, underscoring their potential for battery applications.