Defect structures in supercapacitor electrodes: non-oxide 2D materials and metal oxides


Güngör A., Ammar A. U., Rostas A. M., Erdem E.

JOURNAL OF MATERIALS CHEMISTRY A, vol.13, no.42, pp.36030-36055, 2025 (SCI-Expanded, Scopus)

  • Publication Type: Article / Review
  • Volume: 13 Issue: 42
  • Publication Date: 2025
  • Doi Number: 10.1039/d5ta04716a
  • Journal Name: JOURNAL OF MATERIALS CHEMISTRY A
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Chemical Abstracts Core, Chimica, Communication Abstracts, Compendex, INSPEC, MEDLINE, Metadex, Civil Engineering Abstracts
  • Page Numbers: pp.36030-36055
  • Kocaeli University Affiliated: Yes

Abstract

This review analyzes how crystallographic and interfacial defects govern charge storage in supercapacitor electrodes by shaping electronic structure, charge/ion transport, and redox kinetics. We explicitly decouple chemistry (oxide vs. non-oxide) from dimensionality (2D vs. 3D) to avoid conflation, treating non-oxide 2D materials and metal oxides as orthogonal categories. Across point defects, edge/termination states, and lattice disorder, we show how defect-driven mixed valence, oxygen-vacancy formation, and small-polaron conduction set the density and accessibility of (pseudo)capacitive sites and control the trade-offs between rate capability, stability, and safety. A concise framework connects defect type and distribution to measurable electrochemical responses (capacitance, kinetics, cyclability), supported by multimodal spectroscopy and in situ/operando methods that quantify defect populations under working conditions. Finally, we distill practical design rules-vacancy/termination control, aliovalent doping, and phase/strain engineering-that translate defect chemistry into targeted performance gains, providing a unifying roadmap for defect-engineered supercapacitor electrodes.