Facile Synthesis and Single-Switch Antenna Application of Germanium-Doped Vanadium Dioxide
Facile Synthesis and Single-Switch Antenna Application of Germanium-Doped Vanadium Dioxide
复制标题
DOI：
10.1021/acsaelm.3c00498
复制
发表时间：
2023-06
影响因子：
4.7
通讯作者：
Roberto Prado-Rivera;Cheng-Yu Lai;Mujtaba Ali Haqqani Mohammed;Chen-Yu Chang;Faizan Syed;D. Radu
中科院分区：
文献类型：
--
作者：
Roberto Prado-Rivera;Cheng-Yu Lai;Mujtaba Ali Haqqani Mohammed;Chen-Yu Chang;Faizan Syed;D. Radu
经历从金属到绝缘相变或金属-绝缘体相变（MIT）的材料，由于其在过渡过程中电导率的剧烈变化，在新兴技术中具有巨大的潜力而受到广泛欢迎。在MIT材料中值得注意的是二氧化钒（VO2），并且正在进行的努力集中在调整其MIT相变温度（TMIT）上。本文通过水热法合成了不同锗掺杂水平的vo2锗掺杂纳米粒子，并将其应用于简单的单开关天线中。粉末x射线衍射（XRD）分析表明，在室温下，纯和掺ge的纳米vo2材料均呈现单斜相（M1），低掺杂百分比下掺ge样品的衍射模式没有变化；通过拉曼光谱进一步证实了纯vo2和掺ge vo2的M1相。能谱分析表明，锗在纳米材料中分布均匀。通过场发射扫描电镜（FE-SEM）和透射电镜（TEM）对纳米颗粒的形貌进行了成像，发现随着掺杂浓度的增加，纳米颗粒的形貌发生了从纳米颗粒到纳米片的变化。利用掺杂锗的vo2纳米颗粒分散体来打印天线中的单个开关，这是通过简单的打印工艺获得的。利用矢量网络分析仪对天线性能进行了表征，结果表明锗的掺杂成功地改变了材料的转变温度，证明了控制天线工作频率作为材料掺杂函数的能力。密度泛函理论（DFT）表明，在高掺杂率下，将Ge替换为晶体结构的V位会使晶格扭曲，并减小带隙。这些结果提供了对由掺锗VO2制造的智能开关的潜力的见解。
Materials that undergo a phase transition from metallic to insulating, or metal–insulator transition (MIT), materials have become widely popular for their potential in emerging technologies due to their drastic conductivity change upon transitioning. Notable among the MIT materials is vanadium dioxide (VO2), and ongoing efforts are focused on tuning its MIT phase transition temperature (TMIT). In this report, VO2germanium-doped nanoparticles with various germanium dopant levels were synthesized via a hydrothermal route and used in a simple single-switch antenna. Powder X-ray diffraction (XRD) analysis shows a monoclinic phase (M1) for both the pure and Ge-doped VO2nanomaterials at room temperature, with no change in the diffraction pattern in the Ge-doped samples at low doping percentages; the M1 phase for both pure and Ge-doped VO2was further confirmed by Raman spectroscopy. Energy-dispersive X-ray spectroscopy (EDS) showed Ge uniformly distributed in the nanomaterials. The nanoparticles’ morphology, imaged by field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM), reveals a morphology change from nanoparticles to nanosheets with increased dopant concentration. Ge-doped VO2nanoparticle dispersions were used to print a single switch in an antenna solely obtained through a facile printing process. A vector network analyzer used to characterize the antenna performance showed that the germanium doping successfully changed the transition temperature of the material, demonstrating the capability of controlling the antenna operation frequencies as a function of material doping. Density functional theory (DFT) shows that substituting Ge into a V site of the crystal structure distorts the lattice and reduces the band gap at high doping percentages. These results provide insight into the potential of smart switches fabricated from Ge-doped VO2.