Structural reconstruction of N/S-assisted carbon polyhedral matrix endowed with bimetallic phosphide heterostructures for energy storage


Thondaiman P., Raj C. J., Manikandan R., Cristobal V., KAYA C., Kim B. C.

Sustainable Materials and Technologies, vol.38, 2023 (SCI-Expanded) identifier

  • Publication Type: Article / Article
  • Volume: 38
  • Publication Date: 2023
  • Doi Number: 10.1016/j.susmat.2023.e00742
  • Journal Name: Sustainable Materials and Technologies
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, INSPEC
  • Keywords: Asymmetric supercapacitor, Bimetallic phosphide, Carbon matrix, N/S doped carbon, ZIF-67
  • Yıldız Technical University Affiliated: Yes

Abstract

The synergism of heteroatom-doped carbon polyhedral with mixed-metal networks offers a myriad of electroactive sites that aid in excellent capacitive performance. Herein, a simple precipitation method was implemented to synthesis thiourea functionalized bimetallic ZIF-67 polyhedral as a sacrificial template, facilitating the construction of a superior N/S‑carbon matrix with a Co-Ni-P (CNS/CNP) architecture through various thermal phosphorization processes. The CNS/CNP-2 revealed remarkable attributes after phosphorization at 500 °C, including a maximum specific capacitance of 588 F g−1 at a specific current of 1 A g−1 in 3 M KOH electrolyte. This outstanding performance arises from the synergy of N/S carbon matrix, which significantly increases electroactive sites and structural stability, and Co-Ni-P network, which enhances both redox-active site density and conductivity, facilitating rapid ion diffusion. Furthermore, an asymmetrical supercapacitor was integrated as CNS/CNP-2//AC and revealed a maximum specific energy and power of 30.3 W h kg−1 and 12,489 W kg−1, respectively, with capacitance retention of 90% even for 10,000 cycles. The ASC device was designed as a coin-cell to facilitate real-time applications. The study demonstrates that a synergistic effect between Co–Ni metal ions and a heteroatom matrix can yield an electrode material with a high specific capacity for energy storage devices.