Synthesis and characterization of Nb-doped strontium cobaltite@GQD electrodes for high performance supercapacitors

Poonam R. Kharangarh, Nuggehalli M. Ravindra, Gurmeet Singh, Siva Umapathy

Research output: Contribution to journalArticlepeer-review

25 Scopus citations


In this study, the fabrication and characterization of Nb-doped strontium cobaltite, SrCo0.9Nb0.1O3-δ (SCN), with a significant concentration of oxygen vacancies, as a charge storage material, prepared using sol-gel method, is reported. The results obtained show that the diffusion of oxygen ions is a rate limiting factor for charge storage. The perovskite material, niobium doped strontium cobalitite, on nano graphene sheets such as SCN@GQDs, has been prepared. The Graphene Quantum Dots (GQDs) have been synthesized by using a facile hydrothermal method. The morphology of SCN@GQDs was characterized by FESEM, and TEM. Additional characterization techniques such as PXRD, Raman Spectroscopy, FTIR, TGA/DTA, and BET were performed to observe the structure, porosity, functional groups, defects and thermal behavior of the material. The prepared SCN@GQDs act as an effective electrode material and exhibit high energy density. These SCN@GQD electrodes have been investigated for their electro-chemical properties. The specific capacitance of the synthesized perovskite materials, at 0.1 Ag−1 for supercapacitor, is higher than those of GQDs and SCN due to the improved conductivity, presence of oxygen vacancies and fast ion diffusion between the working electrodes and electrolyte. These properties of SCN@GQD perovskite material, with nanographene sheets, for boosting the capacity of electrodes, provide excellent opportunities for applications in supercapacitors. This perovskite material is superior in comparison to other candidates due to its larger oxygen vacancy concentration and higher oxygen-ion mobility.

Original languageEnglish (US)
Article number105388
JournalJournal of Energy Storage
StatePublished - Nov 1 2022

All Science Journal Classification (ASJC) codes

  • Renewable Energy, Sustainability and the Environment
  • Energy Engineering and Power Technology
  • Electrical and Electronic Engineering


  • Graphene quantum dots
  • Hydrothermal method
  • KFeCN electrolyte
  • Nb-doped strontium cobaltite (SCN)
  • Supercapacitor electrode


Dive into the research topics of 'Synthesis and characterization of Nb-doped strontium cobaltite@GQD electrodes for high performance supercapacitors'. Together they form a unique fingerprint.

Cite this