Enhanced Supercapattery Performance Enabled by Nitrogen-Doped Nb₂O₅ Nanostructures

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Nitrogen doping is a key strategy to improve the electrochemical performance of transition metal oxides.
• Niobium oxide (Nb2O5) is a promising material for energy storage applications.

Purpose of the Study:

• To synthesize nitrogen-doped niobium oxide (Nb_N) using urea as a precursor.
• To investigate the structural, compositional, and electrochemical properties of Nb_N.
• To evaluate the performance of Nb_N in a supercapattery device.

Main Methods:

• Thermal treatment with urea for nitrogen doping.
• X-ray Photoelectron Spectroscopy (XPS) and Raman spectroscopy for material characterization.
• Cyclic voltammetry and galvanostatic charge-discharge tests for electrochemical evaluation.
• Assembly and testing of a supercapattery device.

Main Results:

• Successful nitrogen incorporation into niobium oxide without phase changes, leading to improved crystallinity and larger crystallites.
• XPS analysis revealed increased oxygen vacancies, and Raman analysis indicated local lattice distortion in Nb_N.
• Nb_N exhibited higher specific capacity (1297.37 C g⁻¹) compared to undoped niobium oxide (1108.75 C g⁻¹) at 1 A g⁻¹.
• The supercapattery using Nb_N delivered high energy (496.65 Wh kg⁻¹) and power densities (2771.99 W kg⁻¹), with excellent cycling stability over 5000 cycles.

Conclusions:

• Nitrogen doping significantly enhances the structural and electronic properties of niobium oxide.
• Nb_N demonstrates improved pseudocapacitive behavior, making it suitable for high-performance supercapatteries.
• The developed nitrogen-doped niobium oxide offers a promising material for advanced energy storage solutions.