Temperature-aided multi-faced electrochemistry of copper (II) ions set inside self-assembled 2D homocysteine films attached onto the gold surface

Transformation of the “ordinary,” (originally appearing) electrochemical cyclic voltammetry (CV) signal of Au/homocysteine/Cu(II) two-dimensional (2D) composite to the amplified sharp voltammetric response was studied in electrolyte solutions by means of the fast-scan cyclic voltammetry. The composite was constructed via building self-assembled (SAM) monolayer of L-homocysteine (L-Hcy) or DL-homocysteine (DL-Hcy) on a gold electrode surface with subsequent anchoring copper(II) on it. The change of nature of electrochemical response of the system was triggered by the moderate elevation of temperature of the cell (containing phosphate buffer or sodium chloride serving as electrolyte solutions). Solutions at the first stage of the overall procedure of SAM preparation contained L-Hcy or DL-Hcy components, and the copper chloride, at the second stage, aiming anchoring Cu ions onto SAM. This work is another outstanding case reporting about the remarkable specific CV signal transformation for emerging hybrid 2D bioinspired redox-active 2D systems presumably capable of collective charge-carrier exchange transformations.

Graphical Abstract