Unveiling the Pyridine Functionalized Dicyanostilbene/Reduced Graphene Oxide Electrode Materials for High Performance...

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Pseudocapacitors (PSCs) are key next-generation electrical energy storage (EES) devices, but current inorganic transition metal oxide-based PSCs face cost and stability challenges.
• Organic electrode materials derived from renewable sources are emerging as sustainable alternatives to address these limitations.
• Reduced graphene oxide (rGO) is a promising substrate for electrode development due to its high surface area and conductivity.

Purpose of the Study:

• To enhance the electrochemical performance of pseudocapacitors by developing novel organic electrode materials.
• To investigate the potential of non-covalently functionalized reduced graphene oxide (rGO) with a redox-active organic molecule, (2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(pyridin-4-yl)acrylonitrile) (DCBS), for supercapacitor applications.
• To evaluate the charge storage capacity, device stability, and energy density of the synthesized DCBS/rGO composite electrodes.

Main Methods:

• Non-covalent functionalization of reduced graphene oxide (rGO) with (2Z,2'Z)-2,2'-(1,4-phenylene)bis(3-(pyridin-4-yl)acrylonitrile) (DCBS) to create composite electrode materials.
• Fabrication of three-electrode supercapacitor (SC) and symmetric supercapacitor (SSC) devices using the DCBS/rGO composite electrodes.
• Electrochemical characterization including specific capacitance measurements at various current densities and galvanostatic charge-discharge (GCD) cycling tests to assess stability.

Main Results:

• The DCBS/rGO composite electrode exhibited excellent specific capacitance of 318.98 F g⁻¹ at 0.5 A g⁻¹ in a three-electrode SC setup.
• In an SSC configuration, the DCBS/rGO electrode achieved a specific capacitance (Csp) of 135.10 F g⁻¹ at 0.5 A g⁻¹, with an energy density of 24.31 Wh kg⁻¹ at 1080 W kg⁻¹.
• The SSC device demonstrated remarkable cycling stability, retaining 98.3% of its capacitance after 10,000 GCD cycles at 3 A g⁻¹.

Conclusions:

• The pyridine ring and nitrile functional groups in DCBS contribute to enhanced faradaic redox reactions and electrode stability.
• The DCBS/rGO composite material significantly improves charge storage capacity, device stability, and energy density for supercapacitors.
• This study highlights the potential of DCBS/rGO as a high-performance organic electrode material for advanced electrical energy storage applications.