Tailoring optical and ferroelectric properties in Sb_1-<i>x</i> Bi _<i>x</i> SI van der Waals chalcohalides towards solar absorber applications.

ABSTRACT: The efficiency of solar cells depends on absorber materials whose optical and electronic properties can be precisely tuned for optimal performance. The mixed-anion, van der Waals material SbSI is a promising candidate, offering both a narrow bandgap and strong ferroelectric polarization, which together produce a robust bulk photovoltaic effect and high power conversion efficiency (PCE). Here, we demonstrate that substituting bismuth for antimony in SbSI enables controlled tuning of both the bandgap and ferroelectric properties. Increasing Bi content induces anisotropic changes in the crystal structure, with the bandgap decreasing rapidly at low substitution levels and stabilizing at 1.5 eV for higher Bi concentrations. Concurrently, ferroelectricity is strongly suppressed, as evidenced by

SUBMITTER: Lopez-Paz SA 

PROVIDER: S-EPMC12658473 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature