Electrochemical characterization of titanium nitride microelectrode arrays for charge-injection applications

A key issue in the development of neural prosthetic systems has been the selection of appropriate electrode materials. Titanium Nitride (TIN) offers several advantages including higher surface area provided by its columnar structure and capacitive charge-injection process. Both dc and ac electrochemical techniques were employed in the study. The results showed that no oxidation and reduction peaks were observed within water window potentials. TiN surface was stable when stimulated by a charge balanced biphasic current pulse within the water window. Gassing on the electrode surface appears damaging TiN coating and causing loss of charge injection capacity.

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