Department of Materials Science and Engineering, Technion-Israel Institute of Technology, Haifa 3200003, Israel.
J Chem Phys. 2018 Oct 14;149(14):141103. doi: 10.1063/1.5051202.
The quantum size effect is a well-known fundamental scientific phenomenon. Due to quantum confinement, downscaling a system to small sizes should increase the bandgap of a solid state material. However, in this work, we present an exception: monolayers of nickel hydroxide have smaller bandgaps than their bulk analogues, due to the surface states appearing at energies within the bandgap region. Our findings are obtained by several state-of-the-art first principles calculations.
量子尺寸效应是一种众所周知的基础科学现象。由于量子限制，将系统缩小到较小尺寸应该会增加固态材料的能带隙。然而，在这项工作中，我们提出了一个例外：由于在能带隙区域内出现的表面态，氢氧化镍的单层具有比其体相类似物更小的能带隙。我们的发现是通过几种最先进的第一性原理计算得到的。
