Yasin Alhassan Salman, Li Jiangtian, Wu Nianqiang, Musho Terence
Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506-6106, USA.
Phys Chem Chem Phys. 2016 May 14;18(18):12748-54. doi: 10.1039/c5cp08070c. Epub 2016 Apr 21.
In this study the band gap modulation was studied in response to inorganic ion substitution within a thermally stable UiO-66 metal-organic framework (MOF). A combination of density functional theory prediction in conjunction with experimental predictions were used to map out the complete composition space for three inorganic ions (Zr, Ti, Hf) and three functional groups. The three functional groups include an amino group (NH2), a nitro group (NO2), and a hydrogenated case (H). The smallest band gap that experimentally determined was for a partially substituted UiO-66(Ti5Zr1)-NH2 resulting in 2.60 eV. Theoretical results indicated that Ti can be fully substituted within the lattice resulting in a predicted band gap as low as 1.62 eV. Modulation was a result of a mid-gap state introduced through the amino functionalization and HOMO shifting as a result of increased binding of the Ti-O-C bonds.
在本研究中，研究了热稳定的UiO-66金属有机框架（MOF）内无机离子取代对带隙调制的影响。结合密度泛函理论预测和实验预测，绘制了三种无机离子（Zr、Ti、Hf）和三种官能团的完整组成空间。这三种官能团包括氨基（NH2）、硝基（NO2）和氢化基团（H）。实验测定的最小带隙是部分取代的UiO-66（Ti5Zr1）-NH2的带隙，为2.60 eV。理论结果表明，Ti可以在晶格中完全取代，预测带隙低至1.62 eV。调制是通过氨基官能化引入的中间能隙态以及由于Ti-O-C键结合增加导致的最高占据分子轨道（HOMO）移动的结果。
