论文标题
二维Penta-Nips纸：两个稳定的多晶型物
Two-dimensional Penta-NiPS Sheets: Two Stable Polymorphs
论文作者
论文摘要
发现具有异国特性的新的和稳定的二维（2D）材料对于技术进步至关重要。受到最近报道的PENTA-PDPSE的启发，我们提出了基于第一原理计算的PENTA-NIP作为PENTA-2D材料的新成员。 Penta-NIPS单层在两个多晶型物中保持稳定，包括具有与PENTA-PDPSE相同结构的α相，以及带有旋转的子层的新提出的Beta相。全面的分析表明，这两个阶段在热力学，动态，机械上和热稳定上均为热力学。 Penta-Nips是一种柔软的材料，具有2D Young的EA = 208 nm^-1的模量，而Alpha相位的EB = 187 nm^-1，EA = 184 nm^-1，对于beta阶段而言，EB = 140 nm^-1。有趣的是，Alpha-Penta-NIP在平面方向上显示出几乎为零的泊松比，在延伸时将保持其尺寸。对于电子应用，我们证明了Penta-NIPS是宽带隙半导体，间接带隙为2.35 eV，而对于beta相来说，beta阶段为2.20 eV。
The discovery of new and stable two-dimensional (2D) materials with exotic properties is essential for technological advancement. Inspired by the recently reported penta-PdPSe, we proposed penta-NiPS as a new member of the penta-2D materials based on first-principles calculations. The penta-NiPS monolayer is stable in two polymorphs including the alpha phase with identical structure as penta-PdPSe, and the newly proposed beta phase with rotated sublayers. Comprehensive analysis indicated that both phases are thermodynamically, dynamically, mechanically, and thermally stable. The penta-NiPS is a soft material with 2D Young's modulus of Ea=208 Nm^-1 and Eb=187 Nm^-1 for the alpha phase and Ea=184 Nm^-1 and Eb=140 Nm^-1 for the beta phase. Interestingly, the alpha-penta-NiPS showed nearly zero Poisson's ratios along the in-plane direction, where its dimensions would be maintained when being extended. For electronic applications, we demonstrated that penta-NiPS is the wide band gap semiconductor with an indirect band gap of 2.35 eV for alpha phase, and 2.20 eV for beta phase.
