EXPLORATION OF CAPACITANCE AND REDOX PROPERTIES OF SELF-ASSEMBLED Phe–Phe WITH FERROCENE CONJUGATES: THEIR UTILIZATION IN ENERGY STORAGE DEVICES

Metallocenes have excellent metallic and semiconducting properties. In this work, ferrocene is conjugated with Phe-Phe linked to nucleoside and PNA. Further, electrochemical properties of a new class of peptide templates having dipeptide Phe-Phe conjugated with ferrocene and common capping groups are studied. This yields either rigid needle-like nanorod or spherical morphologies. The triazole containing peptides demonstrate hollow or porous morphologies which are useful in bioelectronics. To study this, Torey carbon electrodes were fabricated with triazole which is conjugated with ferrocene Phe-Phe peptides. These modified electrodes exhibit an enhanced capacitance. The peptide containing ferrocene on both ends (C-/N-termini) furnished the best result among all the peptides, with a 30-fold increase in capacitance compared to the bare, unmodified electrode. Morphological structures and the elemental composition both remain same before and after cyclic voltammetry which confirms the structural stability on Toray carbon electrode surface. Charge storage behavior in potential regions are far from the redox peak which indicates the enhanced capacitance. Hence ferrocene conjugated peptides can be used as the supercapacitors. These results suggest a new direction in the study of the Phe-Phe motif to rationally engineer new nano-architectures involving short metallocene peptide-based biomaterials, supercapacitor device-material, and biosensors.