Instrumentation commercial SECM instrument application

With scanning electrochemical microscopy (SECM) becoming a widely used and mature technique, with a wide range of applications, many in fields outside of fundamental or applied electrochemistry, relatively few researchers construct their own instruments. Thus, we will not deal with homebuilt instruments in this chapter. Those interested in constructing an SECM are referred to a chapter that goes into details about the basics of this in the first edition of this book. A number of companies have commercialized SECM instrumentation (Table 2.1). Thus in this chapter we will discuss, as an example, the operation of a commercial SECM, the CH Instruments model series 900, which is the most frequently used instrument. Information about the other instruments can be obtained from the manufacturers or their websites. Some practical aspects of cell construction and using a commercial SECM are also addressed. 

Finally, SECM offers a new application area for miniaturized electrochemical and biochemical sensors. They can be used in connection with a positioning system to solve, for instance, problems of cell biology, material science, and interfacial geochemistry. Since SECM instruments are now available from different commercial sources, a much broader application in the electrochemical sensor community is expected within the next years. 

SECM instruments suitable for imaging require a PC equipped with an interface board to synchronize acquisition of the electrochemical data with the movement of the tip. Building an SECM for kinetic experiments at fixed tip position or approach curve measurements is relatively easy, but fairly sophisticated software and some electronic work is necessary to construct a computer-controlled apparatus for imaging applications. Details on the construction of SECM instruments can be found elsewhere [6, 13-18, 53, 55]. An SECM is now available commercially from CH Instruments, Inc. (Austin, TX, USA). The instrument employs piezoelectric actuators, a three-axis stage, and a bipotentiostat controlled by an external PC under a 32-bit Windows environment. Various standard electrochemical techniques are incorporated along with SECM imaging, approach curves, and the modes described in Sect. 3.3.I.I. 

As SECM instrumentation has been extensively and thoroughly discussed in Chapter 2 of reference (1) and there are also commercial instruments (e.g., CH Instruments, Heka, and Uniscan) on the market, we mainly focus on experimental aspects encountered in imaging and tip positioning with SECM. Readers who are interested in the design of an SECM instrument can refer to that chapter. We also intend to include here an up-to-date account of the newly developed combined techniques so that interested individual investigators may appreciate the design of SECM-related techniques for their specific applications. 

Because of its simplicity of use and quantitative results, Scanning Electrochemical Microscopy (SECM) has become an indispensable tool for the study of surface reactivity. The fast expansion of the SECM field during the last several years has been fueled by the introduction of new probes, commercially available instrumentation, and new practical applications. Scanning Electrochemical Microscopy, Second Edition offers essential background and in-depth overviews of specific applications in self-contained chapters. 

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