Department of Chemistry, Korea University, Jochiwon, 339-700, Republic of Korea.
Advanced Analysis Center, Korea Institute of Science and Technology, Seoul, 136-791, Republic of Korea.
Small. 2017 May;13(19). doi: 10.1002/smll.201603695. Epub 2017 Mar 15.
Nanowires (NWs) have witnessed tremendous development over the past two decades owing to their varying potential applications. Semiconductor NWs often contain stacking faults due to the presence of coexisting phases, which frequently hampers their use. Herein, it is investigated how stacking faults affect the optical properties of bent ZnSe and CdSe NWs, which are synthesized using the vapor transport method. Polytypic zinc blende-wurtzite structures are produced for both these NWs by altering the growth conditions. The NWs are bent by the mechanical buckling of poly(dimethylsilioxane), and micro-photoluminescence (PL) spectra were then collected for individual NWs with various bending strains (0-2%). The PL measurements show peak broadening and red shifts of the near-band-edge emission as the bending strain increases, indicating that the bandgap decreases with increasing the bending strain. Remarkably, the bandgap decrease is more significant for the polytypic NWs than for the single phase NWs. This work provides insights into flexible electronic devices of 1D nanostructures by engineering the polytypic structures.
纳米线（NWs）在过去二十年中得到了迅猛发展，这归因于它们具有多样化的潜在应用。由于共存相的存在，半导体 NWs 通常含有堆垛层错，这常常会妨碍它们的使用。在此，研究了堆垛层错如何影响使用气相输运法合成的弯曲 ZnSe 和 CdSe NWs 的光学性质。通过改变生长条件，这两种 NWs 都产生了多型纤锌矿 - 闪锌矿结构。通过聚二甲基硅氧烷的机械屈曲使 NWs 弯曲，然后收集具有各种弯曲应变（0-2%）的单个 NW 的微光致发光（PL）光谱。PL 测量表明，随着弯曲应变的增加，近带边发射峰变宽且红移，这表明带隙随弯曲应变的增加而减小。值得注意的是，多型 NWs 的带隙减小比单相 NWs 更为显著。这项工作通过工程化多型结构，为 1D 纳米结构的柔性电子器件提供了新的见解。
