Structure-performance relationship in copper phthalocyanine-based supercapacitor electrodes: influence of substituent geometry from molecular design to electrochemical function


Siyahjani-Gultekin S., ÖZTÜRMEN B. A., Sahin D., Yilmaz G., Ercan B. T., Gultekin B., ...Daha Fazla

DALTON TRANSACTIONS, cilt.55, sa.21, ss.8292-8303, 2026 (SCI-Expanded, Scopus) identifier identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 55 Sayı: 21
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1039/d5dt02965a
  • Dergi Adı: DALTON TRANSACTIONS
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Chemical Abstracts Core, Chimica, Compendex, MEDLINE
  • Sayfa Sayıları: ss.8292-8303
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

This work investigates how the substituent position governs the structure-performance relationship of copper phthalocyanine (CuPc) derivatives used as supercapacitor electrodes. Two positional isomers bearing the same (3,4,5-trimethoxybenzyl)oxy substituent, namely the peripheral derivative (TMe-Cu) and the non-peripheral derivative (n-TMe-Cu), were synthesized and characterized by spectroscopic and structural techniques. Electrochemical evaluation in 1 M H2SO4 using cyclic voltammetry, galvanostatic charge-discharge, electrochemical impedance spectroscopy, and scan-rate-dependent kinetic analyses revealed a pronounced performance advantage for n-TMe-Cu, which delivered a specific capacitance of up to 360 F g(-1) at 1 A g(-1) and retained 80% of its initial capacitance after 5000 cycles. Dunn analysis showed that n-TMe-Cu exhibits a substantially higher surface-controlled contribution than TMe-Cu, indicating that a larger fraction of charge storage proceeds through rapidly accessible interfacial pathways. In conjunction with the observed morphological differences between the two electrodes, these results suggest that non-peripheral substitution promotes a more electrochemically accessible electrode architecture and more favourable charge-storage kinetics. Overall, this study demonstrates that substituent geometry is a key molecular design parameter for regulating electrochemical utilization and rate performance in CuPc-based organic electrode materials.