Nano-electrode arrays

Nano-electrode arrays towards the sensor with the record analytical performances... 

Micro- (and even nano-) electrode arrays are commonly produced with photolithography and electronic beam techniques by insulating of macro-electrode surface with subsequent drilling micro-holes in an insulating layer [136, 137], Physical methods are, however, expensive and, besides that, unsuitable for sensor development in certain cases (for instance, for modification of the lateral surface of needle electrodes). That s why an increasing interest is being applied to chemical approaches of material nanostructuring on solid supports [140, 141],... 

Nano-electrode arrays can be formed through nano-structuring of the electrocatalyst on an inert electrode support. Indeed, if the current of the analyte reduction (oxidation) on a blank electrode is negligible compared to the activity of the electrocatalyst, the former can be considered as an insulator surface. Hence, for the synthesis of nanoelectrode arrays one has to carry out material nano-structuring. Recently, an elegant approach [140] for the electrosynthesis of mesoporous nano-structured surfaces by depositioning different metals (Pt, Pd, Co, Sn) through lyotropic liquid crystalline phases has been proposed [141-143],... 

Prussian blue-based nano-electrode arrays were formed by deposition of the electrocatalyst through lyotropic liquid crystalline [144] or sol templates onto inert electrode supports. Alternatively, nucleation and growth of Prussian blue at early stages results in nano-structured film [145], Whereas Prussian blue is known to be a superior electrocatalyst in hydrogen peroxide reduction, carbon materials used as an electrode support demonstrate only a minor activity. Since the electrochemical reaction on the blank electrode is negligible, the nano-structured electrocatalyst can be considered as a nano-electrode array. 

The resulting Prussian blue-based nano-electrode arrays in FIA demonstrate a sub-ppb detection limit (1 X 10 9 mol I. ) and a linear calibration range starting from the detection limit and extending over seven orders of magnitude of H202 concentrations (1 X 10 9 1 X 10 2 mol L ), which is the most advantageous analytical performance in electroanalysis. As a conclusion from the evidence in this chapter, Prussian... 

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