Dipartimento di Chimica e Chimica Industriale, Università degli Studi di Genova , Via Dodecaneso, 31, 16146, Genova, Italy.
IMEM-CNR , Parco Area delle Scienze 37/A, I-43124 Parma, Italy.
J Am Chem Soc. 2017 Mar 1;139(8):3005-3011. doi: 10.1021/jacs.6b11255. Epub 2017 Feb 14.
We report a low-temperature colloidal synthesis of single-layer, five-atom-thick, β-InSe nanosheets with lateral sizes tunable from ∼300 to ∼900 nm, using short aminonitriles (dicyandiamide or cyanamide) as shape controlling agents. The phase and the monolayer nature of the nanosheets were ascertained by analyzing the intensity ratio between two diffraction peaks from two-dimensional slabs of the various phases, determined by diffraction simulations. These findings were further backed-up by comparing and fitting the experimental X-ray diffraction pattern with Debye formula simulated patterns and with side-view high-resolution transmission electron microscopy imaging and simulation. The β-InSe nanosheets were found to be indirect band gap semiconductors (E = 1.55 eV), and single nanosheet photodetectors demonstrated high photoresponsivity and fast response times.
我们报告了一种低温胶体合成方法，可制备出具有可调横向尺寸（约 300 至 900nm）的单层、五原子厚的β-InSe 纳米片，使用短的氨基腈（双氰胺或氰胺）作为形状控制剂。通过分析不同相的二维片层的两个衍射峰之间的强度比，并通过衍射模拟确定相和纳米片的单层性质。这些发现还通过比较和拟合实验 X 射线衍射图谱与德拜公式模拟图谱以及侧视高分辨率透射电子显微镜成像和模拟得到了进一步支持。β-InSe 纳米片被发现为间接带隙半导体（E=1.55eV），并且单个纳米片光电探测器表现出高光电响应率和快速响应时间。
