Routine Femtogram-Level Chemical Analyses Using Vibrational Spectroscopy and Self-Cleaning Scanning Probe Microscopy Tips

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• 作者：Keunhan Park ; Jungchul Lee ; Rohit Bhargava ; William P. King
• 刊名：Analytical Chemistry
• 出版年：2008
• 出版时间：May 1, 2008
• 年：2008
• 卷：80
• 期：9
• 页码：3221 - 3228
• 全文大小：578K
• 年卷期：v.80,no.9(May 1, 2008)
• ISSN：1520-6882

文摘

Simultaneous structural and chemical characterization ofmaterials at the nanoscale is both an immediate need andan ongoing challenge. This article reports a route toaddress this need, which can be rapidly adopted bypractitioners, by combining the benefits of widely availablescanning probe microscopy and vibrational microspectrometry. In an atomic force microscope (AFM), the probetip can provide a nanoscale topographic image. Here, weuse a temperature-controlled probe tip to selectivelyacquire an analyte from a specified location and determineits mass in a thermogravimetric manner. The tip is thenanalyzed via complementary Raman and Fourier transform infrared microspectrometers, providing a molecularcharacterization of samples down to the femtogram levelin minutes. The probe can be self-cleaned and employedfor repeated use by rapidly heating it to vaporize theanalyte. By combining the established analytical modalities of AFM and vibrational spectrometry, a completephysical and molecular characterization of nanoscaledomains is possible: mass determination is facile, thermal analyses can be integrated on the probe, and theobtained spectral data can be related to existing knowledge bases.