▎ 摘　　要

Graphene oxides are considered to show great promise for the construction of high-performance electrochemical devices for sensing and energy storage applications. Herein, we show that, despite the advantages of graphene oxides, such as facile preparation in bulk quantities and enhanced electrochemical performances, these electrode materials, namely, graphene oxide, chemically reduced graphene oxide, and graphite oxide, show very limited potential windows in the cathodic region because of their inherent electroactivity. This has a profound influence on the use of these materials in electrochemical devices when the cathodic part of the electrochemical window for the reduction of electrolytes is required. The highly limited electrochemical window of these graphene oxides must be taken into account in the construction of new electrochemical devices working in the cathodic region.