Eremina Anna S, Gavrilin Ilya M, Pokryshkin Nikolay S, Kharin Alexander Yu, Syuy Alexander V, Volkov Valentin S, Yakunin Valery G, Bubenov Sergei S, Dorofeev Sergey G, Gavrilov Sergey A, Timoshenko Victor Yu
Phys-Bio Institute, National Research Nuclear University MEPhI, 115409 Moscow, Russia.
Frumkin Institute of Physical Chemistry and Electrochemistry of RAS, 119071 Moscow, Russia.
Nanomaterials (Basel). 2022 Aug 22;12(16):2884. doi: 10.3390/nano12162884.
Layers of germanium (Ge) nanowires (NWs) on titanium foils were grown by metal-assisted electrochemical reduction of germanium oxide in aqueous electrolytes based on germanium oxide without and with addition of sodium silicate. Structural properties and composition of Ge NWs were studied by means of the scanning and transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, and Raman spectroscopy. When sodium silicate was added to the electrolyte, Ge NWs consisted of 1-2 at.% of silicon (Si) and exhibited smaller mean diameter and improved crystallinity. Additionally, samples of Ge NW films were prepared by ultrasonic removal of Ge NWs from titanium foils followed with redeposition on corundum substrates with platinum electrodes. The electrical conductivity of Ge NW films was studied at different temperatures from 25 to 300 °C and an effect of the silicon impurity on the thermally activated electrical conductivity was revealed. Furthermore, the electrical conductivity of Ge NW films on corundum substrates exhibited a strong sensor response on the presence of saturated vapors of different liquids (water, acetone, ethanol, and isopropanol) in air and the response was dependent on the presence of Si impurities in the nanowires. The results obtained indicate the possibility of controlling the structure and electrical properties of Ge NWs by introducing silicate additives during their formation, which is of interest for applications in printed electronics and molecular sensorics.
通过在不含和添加硅酸钠的基于氧化锗的水性电解质中对氧化锗进行金属辅助电化学还原，在钛箔上生长了锗（Ge）纳米线（NWs）层。通过扫描电子显微镜、透射电子显微镜、X射线光电子能谱、X射线衍射和拉曼光谱研究了Ge NWs的结构性质和组成。当向电解质中添加硅酸钠时，Ge NWs含有1-2原子百分比的硅（Si），并且平均直径更小，结晶度更高。此外，通过超声从钛箔上去除Ge NWs，然后再重新沉积在带有铂电极的刚玉衬底上，制备了Ge NW薄膜样品。在25至300°C的不同温度下研究了Ge NW薄膜的电导率，并揭示了硅杂质对热激活电导率的影响。此外，刚玉衬底上的Ge NW薄膜的电导率对空气中不同液体（水、丙酮、乙醇和异丙醇）的饱和蒸汽的存在表现出强烈的传感器响应，并且该响应取决于纳米线中Si杂质的存在。所获得的结果表明，在Ge NWs形成过程中引入硅酸盐添加剂来控制其结构和电学性质是可行的，这对于印刷电子学和分子传感领域的应用具有重要意义。
