The electrochemical properties of glassy carbon (GC) modified by nitrogen ion implantation (a fluence of 1 X 10(16) ions cm(-2)) at various target temperatures were studied by conventional electrochemical methods. The structure of ion-implanted surface layers of carbon materials has already been investigated by Raman spectroscopy, which has revealed that the implantations at high and low target temperatures produce a graphitic and an amorphous structure respectively. GC implanted at high temperatures (150, 300 and 400 degrees C) showed electrochemical properties resembling those of non-implanted GC as a result of its graphitic structure. In contrast, GC implanted at low temperatures (-70 and 30 degrees C) forms an electrode surface with an electrochemically inert nature and a low double-layer capacity, which is due to the formation of an amorphous surface layer. A structure of this type is commonly formed by ion implantation into diamond, highly ordered pyrolytic graphite and GC, which has high electrical resistivity and high wear resistance. It was found that the target temperature during ion implantation has a strong effect on the structure and properties of carbon materials. The electrochemically inert and highly wear-resistive carbon formed by low temperature ion implantation will be useful as a superior stable carbon material.