Rational design of new phases of tin monosulfide by first-principles structure searches

• 来源期刊: 中国科学（物理学 力学 天文学）
• 年，卷（期）: 2018,（10）
• 页码范围: 78-84
• 页数: 7页
• 语种: 中文

摘要

Tin monosulfide (SnS),which is composed of earth-abundant elements,holds promise as useful high-performance solar absorber and thermoelectric material.In addition to the ground-state Pnma phase,a series of metastable phases in different crystalline structures have been reported experimentally or theoretically,yet the phase stability diagrams remain elusive.In this article,we provide a comprehensive materials design study of new phases of SnS using first-principles global optimization structure search calculations.We find that the two-dimensional layered phases are generally more energetically favored than the three-dimensional connected phases.In addition,we discover several new phases with comparable energetics.Four lower-energy phases show clear phonon stabilities evidenced by an absence of imaginary modes.The electronic band structures,carrier transport properties,and absorption spectra of the newly discovered phases are investigated and discussed toward potential applications for solar cells and thermoelectric devices.