Fe-phthalocyanine derived highly conjugated 2D covalent organic framework as superior electrocatalyst for oxygen reduction reaction Articles uri icon

authors

  • Kumar, Anuj
  • Ubaidullah, Mohd
  • PANDIT, BIDHAN
  • Yasin, Ghulam
  • Gupta, Ram K.
  • Zhang, Guoxin

publication date

  • September 2023

start page

  • 1

end page

  • 10

issue

  • 1

volume

  • 18

International Standard Serial Number (ISSN)

  • 2731-9229

abstract

  • Although porphyry systems like metallo-phthalocynine are recognized as promising molecular models for electrocatalytic
    oxygen reduction reaction (ORR), their poor durability and methanol tolerance are still challenges and need improvement
    before being considered for practical applications. Herein, we successfully designed and constructed a Fe-phthalocyanine-
    derived highly conjugated 2D covalent organic framework (2D FePc-COF), using octa-amino-Fe-phthalocyanine
    (OA-FePc) and cyclohexanone as precursors. The prepared 2D FePc-COF was characterized via multiple analytic techniques. The electrochemical studies indicated that prepared 2D FePc-COF was far more superior to OA-FePc and 20%
    Pt/C, displaying anodic shift of 100 and 50 mV (vs RHE) in formal potential, respectively. Moreover, this catalyst also
    demonstrated excellent methanol tolerance and durability (over 10,000 CV cycles). Theoretical investigations revealed
    that due to extended conjugation and elimination of electron donating groups (-NH2), the shifting of dz2-
    orbital (Fe)energy took nearer to π*-orbital (O2), allowing optimum coupling of both the orbitals, thereby enhancing 4e− ORR. This work demonstrates the art of molecular design, aiming at improving catalytic activity of macrocyclic molecular systems towards ORR.

subjects

  • Materials science and engineering

keywords

  • electrocatalytic activity; fe-phthalocyanine; molecular catalysts; oxygen reduction reaction