納米傅里葉紅外光譜儀nano-FTIR
------具有10nm空間分辨率的納米紅外光譜儀
neaspec公司的nano-FTIR技術
現代化學的一大科研難題是如何實現在納米尺度下對材料進行無損化學成分鑒定?，F有的一些高分辨成像技術，如電鏡或掃描探針顯微鏡等，在一定程度上可以有限的解決這一問題，但是這些技術本身的化學敏感度太低，已經無法滿足現代化學納米分析的要求。而另一方面，紅外光譜具有很高的化學敏感度，但是其空間分辨率卻由于受到二分之一波長的衍射限限制，只能達到微米別，因此也無法進行納米別的化學鑒定。
近期neaspec公司利用其的散射型近場光學技術發展出來的nano-FTIR納米傅里葉紅外光譜技術，使得納米尺度化學鑒定和成像成為可能。這一技術綜合了原子力顯微鏡的高空間分辨率，和傅里葉紅外光譜的高化學敏感度，因此可以在納米尺度下實現對幾乎所有材料的化學分辨。因而，現代化學分析的納米新時代從此開始。
neaspec公司的散射型近場技術通過干涉性探測針尖掃描樣品表面時的反向散射光，同時得到近場信號的光強和相位信號。當使用寬波紅外激光照射AFM針尖時，即可獲得針尖下方10nm區域內的紅外光譜，即nano-FTIR.
nano-FTIR 光譜與標準FTIR光譜高度吻合：
在不使用任何模型矯正的條件下，nano-FTIR傅里葉紅外光譜儀獲得的近場吸收光譜所體現的分子指紋特征與使用傳統FTIR光譜儀獲得的分子指紋特征吻合度高（如下圖），這在基礎研究和實際應用方面都具有重要意義，因為研究者可以將nano-FTIR光譜與已經廣泛建立的傳統FTIR光譜數據庫中的數據進行對比，從而實現快速準確的進行納米尺度下的材料化學分析。對化學成分的高敏感度與超高的空間分辨率的結合，使得nano-FTIR成為納米分析的特工具。
應用案例：
nano-FTIR傅里葉紅外光譜儀可以應用到對納米尺度樣品污染物的化學鑒定上。下圖顯示的Si表面覆蓋PMMA薄膜的橫截面AFM成像圖，其中AFM相位圖顯示在Si片和PMMA薄膜的界面存在一個100nm尺寸的污染物，但是其化學成分無法從該圖像中判斷。而使用nano-FTIR在污染物中心獲得的紅外光譜清晰的揭示出了污染物的化學成分。通過對nano-FTIR獲得的吸收譜線與標準FTIR數據庫中譜線進行比對，可以確定污染物為PDMS顆粒。
nano-FTIR對納米尺度污染物的化學鑒定
AFM表面形貌圖像 (左), 在Si片基體（暗色區域Ｂ）與PMMA薄膜（Ａ）之間可以觀察到一個小的污染物。機械相位圖像中（中），對比度變化證明該污染物的是有別于基體和薄膜的其他物質。將點Ａ和Ｂ的nano-FTIR 吸收光譜（右），與標準紅外光譜數據庫對比， 獲得各部分物質的化學成分信息. 每條譜線的采集時間為7min, 光譜分辨率為13 cm-1. （"Nano-FTIR absorption spectroscopy of molecular fingerprints at 20 nm spatial resolution.,”,F. Huth, A. Govyadinov, S. Amarie, W. Nuansing, F. Keilmann, R. Hillenbrand,）Nanoletters 12, p. 3973 (2012)）
主要技術參數配置：
■ 反射式 AFM-針尖照明 ■ 標準光譜分辨率: 6.4/cm-1 ■ 保護的無背景探測技術 ■ 基于優化的傅里葉變換光譜儀 ■ 采集速率： Up to 3 spectra /s | ■ 高性能近場光譜顯微優化的探測模塊 ■ 可升光譜分辨率：3.2/cm-1 ■ 適合探測區間：可見，紅外(0.5 – 20 μm) ■ 包括可更換分束器基座 ■ 適用于同步輻射紅外光源 NEW!!! |
部分發表文章：
Science (2017)doi:10.1126/science.aan2735
Tuning quantum nonlocal effects in graphene plasmonics
Nature Nanotechnology (2017)doi:10.1038/nnano.2016.185
Acoustic terahertz graphene plasmons revealed by photocurrent nanoscopy
Nature Photonics (2017)doi:10.1038/nphoton.2017.65
Imaging exciton–polariton transport in MoSe2 waveguides
Nature Materials (2016)doi:10.1038/nnano.2016.185
Acoustic terahertz graphene plasmons revealed by photocurrent nanoscopy
Nature Materials (2016)doi:10.1038/nmat4755
Thermoelectric detection and imaging of propagating graphene plasmons
國內用戶部分發表文章：
Nat. Commun.8, 15561(2017)
Imaging metal-like monoclinic phase stabilized by surface coordination effect in vanadium dioxide nanobeam
Adv. Mater. 29, 1606370 (2017)
The Light-Induced Field-Effect Solar Cell Concept –Perovskite Nanoparticle Coating Introduces Polarization Enhancing Silicon Cell Efficiency
Light- Sci & Appl 6, 204(2017)
Effects of edge on graphene plasmons as revealed by infrared nanoimaging
Light- Sci & Appl，中山大學accepted (2017)
Tailoring of electromagnetic field localizations by two-dimensional graphene nanostructures
Nanoscale9, 208 (2017)
Study of graphene plasmons in graphene–MoS2 heterostructures for optoelectronic integrated devices
Nano-Micro Lett.9,2 (2017)
Molybdenum Nanoscrews: A Novel Non-coinage-Metal Substrate for Surface-Enhanced Raman Scattering
J. Phys. D: Appl. Phys. 50, 094002 (2017)
High performance photodetector based on 2D CH3NH3PbI3 perovskite nanosheets
ACS Sens. 2, 386 (2017)
Flexible, Transparent, and Free-Standing Silicon Nanowire SERS
Platform for in Situ Food Inspection
Semiconductor Sci. and Tech.32,074003 (2017)
PbI2 platelets for inverted planar organolead Halide Perovskite solar cells via ultrasonic spray deposition
部分用戶好評與列表（排名不分先后）
neaspec公司產品以其穩定的性能、高的空間分辨率和良好的用戶體驗，得到了國內外眾多科學家的認可和肯定......
Prof. Dmitri Basov 美國 加州大學 University of California San Diego | "The neaSNOM microscope with it’s imaging and nano-FTIR mode is the most useful research instrument in years, bringing genuinely new insights." | |
Dr. Jaroslaw Syzdek 美國 勞倫斯伯克利實驗室 Lawrence Berkeley National Laboratory | "We were looking for a flexible research tool capable of characterizing our energy storage materials at the nanoscale. neaSNOM proofed to be the system with the highest spatial resolution in infrared imaging and spectroscopy and brings us substantial new insights for our research” | |
陳煥君 教授 中山大學 Sun Yat-sen University | "The neaSNOM microscope boosted my research in plasmonic properties of noble metal nanocrystals, optical resonances of dielectric nanostructures, and plasmon polaritons of graphene-like two dimensional nanomaterials." | |
Prof. Rainer Hillenbrand Research Center Co-Founder and Scientific Advisor | "After many years of research and development in near-field microscopy, we finally made our dream come true to perform infrared imaging & spectroscopy at the nanoscale. With neaSNOM we can additionally realize Raman, fluorescence and non-linear nano-spectroscopy." | |
| Dr. Dangyuan Lei The Hong Kong Polytechnic University Department of Applied Physics Hong Kong | "We propose to establish a complete set of nano-FTIR and scattering-type SNOM in order to stay competitive in nanophotonics research as well as to maintain our state-of-the-art design and fabrication of novel nanomaterials. Only because of the unique technology from neaspec we were able to win this desirable university grant." | |
Prof. Dan Mittleman Brown University School of Engineering USA | "The neaSNOM near-field microscope and it’s user-friendly software offer us an incredible flexibility for the realization of our unique experiments – without compromises in robustness, handling and ease-of-use." | |
| Dr. Raul Freitas Centro Nacional de Pesquisa em Energia e Materiais (CNPEM) Laboratório Nacional de Luz Síncrotron (LNLS) Brazil | "The great stability and robustness of the neaSNOM are key features for serving our diverse user’s demands. The neaSCAN software is user-friendly and intuitive allowing fresh users to quickly start measuring." | |
| Prof. Dr. Rupert Huber University of Regensburg Department of Phyics Germany | "The unique dual beam-path design of the neaSNOM near-field microscope makes neaspec the natural choice for ultrafast spectroscopy at the nanoscale." |
