Nickel Metal–Organic Frameworks of Amino Acid Tyrosine-Functionalized Naphthalenediimide for Pseudocapacitor Applications

Abstract

Pseudocapacitors (PSCs) have attracted researcher's attention as electrical energy-storage (EES) devices for modern technology with higher electrochemical performance. PSCs exhibit higher power density (PD), and structural manipulation of electrode should be done to achieve great energy density, longer cycling stability, and simple device architecture. Metal−organic framework has been one of the targeted electrode materials for PSC applications. To achieve higher efficiency and stability, newer materials based on π-conjugated redox molecular structures and biologically important amino acids are an attractive choice for the researchers. Herein, we synthesized nickel chloride (Ni), tyrosine (Tyr,) and naphthalene diimide (NDI) based Ni-Tyr-NDI-MOF via salvo thermal method. The active Ni-Tyr-NDI-MOF material is utilized for the fabrication of Ni-Tyr-NDI-MOF/graphite foil (GF) electrode. The Ni-Tyr-NDI-MOF/ GF electrode in the three-electrode supercapacitor configuration displayed great achievement at 5 mV s −1 scan rate with a specific capacitance (C sp ) of 294.20 and 330.71 F g −1 at 1 A g −1 current density within the 0.0 to 1.4 V potential range. Furthermore, Ni-Tyr-NDI-MOF/GF-based symmetric supercapacitor (SSC) was fabricated at 0.5 A g −1 which displayed a C sp of 180 F g −1 , an energy density of 44.1 Wh kg −1 , and a power density of 1265.02 W kg −1 . The SSC device exhibited excellent cycling stability of 82% after 10,000 galvanostatic charging−discharging cycles. We believe that the Ni-Tyr-NDI-MOF/GF electrode with its excellent electrochemical performance has great potential in EES applications.