Theoretical study on ferroelectric nitrides with super-wurtzite structures for solar energy conversion applications

Area of Science:

• Materials Science
• Solid State Physics
• Computational Chemistry

Background:

• Polarized structured nitride semiconductors offer unique, eco-friendly electronic properties.
• Investigating novel materials for sustainable energy applications is crucial.

Purpose of the Study:

• To determine the stability, ferroelectricity, and photocatalytic/photovoltaic properties of super-wurtzite Mg2XN3 (X = Bi, Mo, Nb, Sb, Ta, Tc, W).
• To identify promising candidates for photocatalytic water splitting and photovoltaic applications.

Main Methods:

• First principles calculations were employed to analyze material properties.
• Phonon frequencies, elastic coefficients, and ferroelectric analysis were used to assess stability and properties.

Main Results:

• Mg2XN3 compounds with X = Sb, Ta, Bi, and Nb were identified as stable polar nitrides.
• Mg2XN3 (X = Sb, Ta, Nb) exhibit strong ferroelectric polarization, enabling UV light absorption for photocatalytic water splitting.
• Mg2BiN3 demonstrates potential as a photovoltaic material due to its favorable electronic band structure, high electron mobility, high absorption coefficient, and significant ferroelectric polarization.

Conclusions:

• Several Mg2XN3 compounds are stable polar nitrides with potential for energy applications.
• Specific compositions are suitable for efficient hydrogen production via photocatalytic water splitting.
• Mg2BiN3 emerges as a promising material for next-generation photovoltaic devices.