Binder-free cauliflower-like NiCoP@EG nanocomposite electrode with superhydrophilic surface for high-performance asymmetric supercapacitors

Erdemir F., Baskara F., Güler O., Canakci A., Varol T., Reis H. A.

JOURNAL OF ENERGY STORAGE, cilt.147, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 147
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1016/j.est.2025.120213
  • Dergi Adı: JOURNAL OF ENERGY STORAGE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

In this study, a binder-free cauliflower-like NiCoP nanostructure is synthesized on expanded graphite (EG) paper through a sequential solvothermal, phosphorization, and electrolysis process. The hierarchically textured surface morphology, characterized by a rough and porous appearance, together with the intrinsic surface chemistry, enables superhydrophilic behavior. Surface wettability and structural properties were characterized in detail by contact angle measurements, SEM, and XPS analyses. Electrochemical tests revealed an excellent areal capacitance of 5.96 F cm(-2) (2384 F/g) at 1 mA cm(-2) and outstanding cycling stability, retaining 113.1 % of its initial capacitance after 6000 charge-discharge cycles. Moreover, a CR2032-type asymmetric supercapacitor is assembled using NiCoP@EG as the positive and AC@EG as the negative electrode. The device delivers 848 mF cm(-2) at 1 mA cm(-2), along with a high energy density of 231.1 mu Wh cm(-2) at a power density of 8946.2 mu W cm(-2), indicating outstanding rate capability. These findings highlight the synergistic advantages of combining morphology-engineered NiCoP with a binder-free EG platform, offering a promising route toward high-performance microscale energy storage systems.