Synthesis and Characterization of Ag nanowires and nanoplates
We successfully synthesized Ag nanowires and nanoplates by chemical vapor transport and condensation (CVTC) method. Although a variety of semiconductor nanowires were synthesized for a long time and many of which were investigated, metal nanowires and nanoplates are still an unexplored field in synthesis and their applications compared with semiconductor nanowires.
Herein we introduce Ag nanowires and nanoplates can be synthesized by simple method through controlling experiment conditions like temperature or pressure. These synthesized nanowires and nanoplates are characterized by scanning electron microscope, transmission electron microscope, X-ray diffractometer.
Synthesis and Characterization of Ag Nanowires
Ag nanowires were synthesized through a simple chemical vapor transport method.
Synthesis conditions are followed with quite high temperature, atmospheric pressure, and proper Argon flow on substrates such as $SrTiO_3(100)$ and m-plane $Al_2O_3$. The diameter and length of the Ag nanowires were in range of 100 to 200 nm and 5 to 10 μm, respectively. Ag nanowires are well-faceted and have grown in two orientation at anlges 90°(or 180°) to one another on SrTiO3(100) substrate. Also Ag nanowires have grown parallel to each other on m-plane Al2O3(10 0)
substrate. Synthesized Ag nanowires were characterized with XRD (X-Ray Diffractometer), SEM (Scanning Electron Microscope), TEM (Transmission Electron Microscope), TEM - EDS (Energy Dispersive Spectroscopy).
Synthesis and Characterization of Ag Nanoplates
We have fabricated Ag nanoplates via simple vapor phase growth. Synthesis conditions are similar to experimental details of nanowires except substrates and temperature. Ag nanoplates were epitaxial growth on various substrates (c-plane, a-plane, r-plane Al2O3). Field emission properties have been observed in Ag naoplates. Also XRD, SEM, TEM, EDS and ED pattern study were employed for the characterization of synthesized Ag nanoplates. The diameter of nanoplates
were about 100-200 nm. Also length and width of the nanoplates were about 5 to 20 μm.
1차원 나노구조 물질 중에서도 금속 나노선은 (Metal nanowire) 초고집적 자성 기록 (Ultrahigh-density magnetic recording), 초고속 광 스위치 (Ultrafast optical switching), 극초단파 소자 (Microwave devices) 그리고 수소센서 (Hydrogen sensor) 혹은 Bio - 센서로의 (Bio-sensor using SERS) 잠재적 가능성 (Potential application) 때문에 큰 관심을 받고 있다. 그러나 금속 나노선은 다른 여느 반도체 나노선과 달리 합성도 어려울 뿐만 아니라 합성에 성공을 하더라도 몇몇 귀금속을 (Noble metal) 제외하고는 바로 산화가 일어나 금속 자체의 성질을 잃어버리는 등 응용에 큰 어려움을 격고 있다. 이것을 막기 위해 많은 노력이 진행 중에 있으며, 앞으로도 해결해야만 하는 큰 난제로 남아 있다. 많은 금속들 중에서 은 anistropic 나노구조(e.g. rods, wires, plates, discs)는 SERS(Surface enhanced Raman scattering)과 nonlinear광학 성질 등의 독특한 광학 성질로 널리 연구되고 있다. 우리는 나노선과 나노판을 화학적 기상 이동방식을 이용하여 성공적으로 합성하였다. 이 논문에서는 은 나노선과 나노판을 온도나 압력 같은 실험적 조건을 변형 시키므로 간단하게 합성 할 수 있었고, 이렇게 합성한 은 나노선과 나노판에 대해서 주사 전자 현미경, 투과 전자 현미경, XRD 등을 이용해여 분석하였다.
