掃描式電化學顯微鏡的歷史與最新應用

The History of Scanning Electrochemical Microscopy and Its Applications on Scanning 2D-material Mxene

蔡沛先(Pei-Hsien Tsai) ； 林晏慈(Yen-Tzu Lin) ； 徐悅恬(Yueh-Tien Hsu) ； 林子恩(Tzu-En Lin)

《化學》 79卷1期 (2021/03) Pp. 3-11

https://doi.org/10.6623/chem.202103_79(1).008

摘要

電化學掃描式顯微鏡（SECM）為一種表面探針掃描分析技術，其原理是利用微電極或奈米電極探針的尖端與樣品間產生的交互反應，來分析的材料表面形貌或是檢測電化學活性物質的分布，並形成高分辨率的影像。SECM通常是由電化學工作站、三電極系統以及精密馬達所組成。其中探針是工作電極，另外還有輔助電極以及參考電極。傳統的工作電極以玻璃封裝的鉑電極為主，然而玻璃電極操作困難，不但易斷，還可能因為樣品表面的凹凸不平導致訊號受干擾。為了解決這個問題，我們發展了軟電極（系統），可以用接觸模式（contact mode）掃描樣品。也有人將SECM結合其他儀器，例如原子力顯微鏡（AFM）、掃描離子電導顯微鏡（SICM），來解決傳統電極的問題並且獲得更多測量資訊。目前SECM以及相關技術已廣泛應用於多種領域，如分析化學、電催化研究、腐蝕研究及表面修飾等。本篇文章除了介紹SECM操作的原理與歷史起源外，還統整並討論了目前的研究現況，並展示最新的研究，利用SECM掃描MXene奈米顆粒。MXene是由幾個原子層厚度的二維過渡金屬碳化物、氮化物或碳氮化物構成，其具獨特的金屬導電性、良好的親水性，高表面積比和廣泛可調等特性，已應用在能量存儲、傳感、光電、催化和生物醫學等眾多領域。SECM的圖片可以確認MXene的高導電性，並且分析MXene在聚偏二氟乙烯膜（PVDF）上的分布。

關鍵字

掃描式電化學顯微鏡 ； 軟電極 ； 軟探針 ； 二維材料 ； 表面分析 ； MXene

並列摘要

Scanning electrochemical microscope (SECM) is a scanning probe technique, which measures the Faraday currents in local area and analyzes the electrochemical behavior of the sample interphase through the tip and sample interaction. These spatially resolved signals acquired from the probe, an ultramicroelectrode (UME) tip (or nanoelectrodes) allow imaging of the sample surfaces by moving or scanning the tip across the surface in the x-y plane (or another plane). SECM is usually constructed by a three electrodes system which consists of a working electrode (UME), an auxiliary electrode, a reference electrode and a potentiostat. However, the conventional working electrode is glass-encapsulated Pt electrode, which is difficult to manipulate. To solve this problem, researchers developed Soft-Probe SECM scanning in contact mode, or combined SECM with other techniques, such as atomic force microscope (AFM) and scanning ion conductance microscope (SICM) In recent years, SECM has been widely used in many fields, such as analytical chemistry, electrocatalysis, corrosion and surface modification. In this paper, we introduce the working principle and history of SECM, as well as commonly used operation modes. The current research about SECM is summarized and discussed. Moreover, the novel results of SECM scanning image of MXene is presented. MXene is a family of two-dimensional transition metal carbides, nitrides and carbonitrides. It has high conductivity, good hydrophilicity, and high biocompatibility so it has been applied in energy storage, sensing, optoelectronics, catalysis, and biomedicine. Finally, we explored the properties of MXene by using SECM coupled with soft probe scanning in contact mode.

並列關鍵字

Scanning electrochemical microscopy ； Soft microelectrode ； Soft probe ； Surface analysis ； MXene