Enhancing hybrid supercapacitor performance using porous bimetallic nickel cobalt telluride hexagonal nanoplates

Abstract

Mixed metal chalcogenides have garnered significant attention as promising electrode materials for energy storage applications, particularly in hybrid supercapacitors, owing to their exceptional electrochemical properties. While sulfides and selenides have been extensively investigated, tellurium-based chalcogenides despite their high intrinsic electrical conductivity and good redox behavior remain relatively underexplored in such configurations. To bridge this knowledge gap, we present the rational design and synthesis of porous NiCoTe (NCT) hexagonal nanoplates through a facile hydrothermal method followed by a tellurization process. The incorporation of bimetallic telluride into a meticulously engineered porous architecture induces marked synergistic interactions, culminating in an electrode material endowed with exceptional electrochemical properties. The NCT electrode demonstrates a remarkable specific capacity of 1283 C g⁻¹ at 1 A g⁻¹, exceptional rate capability (73% retention at 48 A g⁻¹), and outstanding cycling stability (90.23% capacity retention over 12 000 cycles at 24 A g⁻¹). To assess its practical viability, a hybrid supercapacitor (AC//NCT) was fabricated, pairing the NCT cathode with an activated carbon (AC) anode. The assembled device delivers an impressive energy density of 65.46 W h kg⁻¹ while exhibiting robust long-term stability, retaining 87.2% of its initial capacity after 12 000 cycles. These findings not only underscore NCT as a high-performance electrode material but also establish a strategic framework for the development of advanced transition metal telluride (TMT)-based architectures.