- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Monotectic growth evolution and raman scattering of self-assembled ZnO hierarchical micro-nanostructures
摘要： The self-assembled hierarchical micro-nanostructures with geometric complexity and/or constituent diversity are becoming a promising class of candidates for the next generation nanotechnology. Different from conventional vapor-liquid-solid (VLS) eutectic liquid droplets for one-dimensional (1D) nanowires, the Zn-Bi VLS monotectic liquid droplets are employed to build 1D, 2D and 3D ZnO into 3D hierarchical micro-nanostructures. As-obtained micro-nanostructures are well de?ned self-assembly and have not yet been observed in the conventional eutectic alloys. The synergy of monotectic droplets and nonthermal equilibrium is responsible for the evolution of ZnO hierarchical micro-nanostructures. Raman spectra show that E2H and E1L modes are shifted slightly towards the high-wavenumber side by an amount of 3.7 and 2 cm?1 as compared with undoped ZnO nanowires and an additional peak at 519.5 cm?1 is associated with Bi38OZn60. The results manifest that 3D ZnO micro-nanoarchitectures possess a bulk phonon structure. The monotectic liquid droplet route presented in this paper may offer a new opportunity to the fabrication of hierarchical nanostructures for realistic technology platforms with multifunctional coupling and interplay.
关键词： nanowires,growth mechanism,nanofabrications,nanostructures,Raman scattering
更新于2025-09-16 10:30:52
-
Nonlinear emission from silver-coated 3D hollow nanopillars
摘要： High aspect ratio metal nanostructures have been the subject of a number of studies in the past, due to their pronounced resonances in the infrared that can be exploited to enhance vibrational spectroscopies. In this work, we investigate the nonlinear optical response of both individual and closely-packed assemblies of vertical hollow Ag nanopillars upon excitation with ultrafast laser pulses. In particular, the analysis of their nonlinear emission spectra evidences an intense two photon photoluminescence (TPPL) emission and a neat signature of second harmonic generation (SHG). Given the relatively low background, this pronounced nonlinear emission could be employed as a local probe for analytes trapped at the surface of the nanopillar or flowing through it. For this reason, these nanostructures may become appealing building blocks in multi-purpose devices for nonlinear photonics and sensing.
关键词： Two Photon Photoluminescence,Ag Nanopillars,Localized Surface Plasmons,3D nanofabrications,Second Harmonic Generation
更新于2025-09-09 09:28:46