AI-Based Stoichiometric Engineering of Zinc Cobaltite

Syed Shehzad Hassan; S.M. Hassan Raza; Iqra Nazeer; Syed Amer Mahmood

Authors

Syed Shehzad Hassan Department of Physics Government College University Lahore
S.M. Hassan Raza Department of Space Science, Punjab University
Iqra Nazeer Department of Space Science, University of Punjab Lahore
Syed Amer Mahmood Department of Space Science, University of The Punjab Lahore

Keywords:

Stoichiometric Variations, Zinc Cobaltite, Electrochemical Performance, Structure-Property-Performance

Abstract

This study investigates the impact of stoichiometric variations and defect engineering on the structural, electrical, and electrochemical properties of zinc cobaltite (Zn_1-xCo_(1+x)-O4) synthesized via a modified sol-gel method. By systematically varying the Zn: Co ratio, an optimal composition, Zn_0.75Co_2.25O₄, was identified, demonstrating superior performance metrics. SEM images confirmed the morphological changes of spinel phase, with lattice parameter variations correlating to Zn content. EIS analysis revealed that moderate oxygen vacancies significantly enhanced conductivity, with Zn_0.75Co_2.25O₄ exhibiting the highest electrical and electrochemical performance. The optimized material achieved a specific capacity of 290 mAh/g at 1 A g^-1 and retained ~90% capacity after 500 cycles, surpassing prior benchmarks. This study provides a detailed understanding of the structure-property-performance relationship, highlighting the potential of defect-engineered zinc cobaltite for advanced energy storage applications.

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