Lizunova Anna, Mazharenko Anastasia, Masnaviev Bulat, Khramov Egor, Efimov Alexey, Ramanenka Andrei, Shuklov Ivan, Ivanov Viktor
Moscow Institute of Physics and Technology, National Research University, Moscow 141700, Russia.
Stepanov Institute of Physics of the National Academy of Sciences of Belarus, 220072 Minsk, Belarus.
Materials (Basel). 2020 Oct 5;13(19):4431. doi: 10.3390/ma13194431.
We report the spark discharge synthesis of aerosol germanium nanoparticles followed by sintering in a tube furnace at different temperatures varying from 25 to 800 °C. The size, structure, chemical composition and optical properties were studied. We have demonstrated a melting mechanism of nanoparticles agglomerates, the growth of the mean primary particle size from 7 to 51 nm and the reduction of the size of agglomerates with a temperature increase. According to transmission electron microscopy (TEM) and Fourier transform infrared (FTIR) data, primary nanoparticles sintered at temperatures from 25 to 475 °C basically have a structure of Ge crystals embedded in a GeOx amorphous matrix, as well as visible photoluminescence (PL) with the maximum at 550 nm. Pure germanium nanoparticles are prepared at temperatures above 625 °C and distinguished by their absence of visible PL. The shape of the experimental UV-vis-NIR extinction spectra significantly depends on the size distribution of the germanium crystals. This fact was confirmed by simulations according to Mie theory for obtained ensembles of germanium nanoparticles.
我们报道了通过火花放电合成气溶胶锗纳米颗粒，随后在管式炉中于25至800°C的不同温度下进行烧结。研究了其尺寸、结构、化学成分和光学性质。我们展示了纳米颗粒团聚体的熔化机制，平均一次粒径从7nm增长到51nm，并且随着温度升高团聚体尺寸减小。根据透射电子显微镜（TEM）和傅里叶变换红外光谱（FTIR）数据，在25至475°C温度下烧结的一次纳米颗粒基本上具有嵌入GeOx非晶基质中的Ge晶体结构，以及在550nm处具有最大值的可见光致发光（PL）。在625°C以上的温度下制备了纯锗纳米颗粒，其特点是没有可见PL。实验性紫外-可见-近红外消光光谱的形状显著取决于锗晶体的尺寸分布。根据米氏理论对所得锗纳米颗粒集合进行的模拟证实了这一事实。
