粉末样品的原子力显微镜研究方法

Study on the powder imaging method of atomic force microscopy

本文提出了用纯净水对粉末样品充分湿润以后,把粉末样品置于空气中,待其自然蒸发到样品表面只有分子结合水以后再进行AFM扫描成像的粉末样品原子力显微镜研究方法。通过分析实验过程发现,原始粉末样品颗粒表面大量的过剩电荷被分子结合水层中和,解决了扫描过程中颗粒易于粘到针尖上的问题;颗粒间存在的分子结合水与毛细管水,使颗粒之间结合牢固,解决了扫描过程不稳定的问题。实验结果表明,该法获得的粉末样品形貌图清晰真实,且具有简单易行,适用范围广的特点。另外,该方法提出了一种针尖在大气中振动,而被扫描样品在液体中的复合扫描环境,具有进一步深入研究和推广的价值。

In this article, a method on powder sample imaging of atomic force microscopy was presented. The powder sample was wetted up by pure water and placed in the air, and it was put into the atomic force microscope to be scanned after pure water was vaporized till there was only molecular binding water on the powder sample surface. With the analysis of the experimental process, we found that the problem of adhesion of the particles to the tip when using AFM to scan the sample＇ s surface was solved through molecular binding water neutralized the residual charges on the surface of the particles. And the difficulty of the instability of the particles when the scanning process was going on was conquered by molecular binding water and capillary water which existed in the interspaces of the particles and made them band together hard. The powder sample morphologies obtained were clear and genuine. The experimental results indicated this method was easy but feasible and could be applied widely. Furthermore, a new and complex scanning circumstance of AFM was occured in this method, in which the tip vibrated in the air but the scanning sample was in water. This concept of complex scanning circumstance is worth more investigation and generalizing.