Institute for Advanced Ceramics, School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, PR China.
College of Engineering Materials Science and Engineering, University of Michigan, Michigan, United State.
Sci Rep. 2017 Jan 13;7:39866. doi: 10.1038/srep39866.
Increasing structural complexity at nanoscale can permit superior control over photophysical properties in the precursor-derived semiconductors. We demonstrate here the synthesis of silicon carbonitride (SiCN)/boron nitride (BN) nanocomposites via a polymer precursor route wherein the cobalt polyamine complexes used as the catalyst, exhibiting novel composite structures and photophysical properties. High Resolution Transmission Electron Microscopy (HRTEM) analysis shows that the diameters of SiCN-BN core-shell nanocomposites and BN shells are 50‒400 nm and 5‒25 nm, respectively. BN nanosheets (BNNSs) are also observed with an average sheet size of 5‒15 nm. The photophysical properties of these nanocomposites are characterized using the UV-Vis and photoluminescence (PL) analyses. The as-produced composites have emission behavior including an emission lifetime of 2.5 ns (±20 ps) longer observed in BN doped SiCN than that seen for SiC nanoparticles. Our results suggest that the SiCN/BN nanocomposites act as semiconductor displaying superior width photoluminescence at wavelengths spanning the visible to near-infrared (NIR) spectral range (400‒700 nm), owing to the heterojunction of the interface between the SiC(N) nanowire core and the BN nanosheet shell.
在纳米尺度上增加结构复杂性可以允许对前驱体衍生半导体的光物理性质进行更好的控制。我们在这里展示了通过聚合物前驱体途径合成硅碳氮化物 (SiCN)/氮化硼 (BN) 纳米复合材料的方法，其中使用的钴多胺配合物作为催化剂，表现出新颖的复合结构和光物理性质。高分辨率透射电子显微镜 (HRTEM) 分析表明，SiCN-BN 核壳纳米复合材料和 BN 壳的直径分别为 50-400nm 和 5-25nm。还观察到 BN 纳米片（BNNSs），平均片尺寸为 5-15nm。使用紫外-可见和光致发光 (PL) 分析对这些纳米复合材料的光物理性质进行了表征。所制备的复合材料具有发射行为，包括在 BN 掺杂 SiCN 中观察到的发射寿命比 SiC 纳米颗粒长 2.5ns（±20ps）。我们的结果表明，SiCN/BN 纳米复合材料作为半导体，在可见到近红外 (NIR) 光谱范围（400-700nm）内表现出优异的宽带光致发光，这是由于 SiC(N) 纳米线核和 BN 纳米片壳之间的界面异质结所致。
