Fabrication of NbTe2@rGO nanosheet by hydrothermal route for cost-effective supercapacitor electrode

Abstract

The expansion of energy storage devices with extensive stability and high energy density is a crucial area of research that requires immediate attention. In light of these requirements, it was worth noting that supercapacitor (SC_s) exhibit great potential as viable options for achieving these demands. Supercapacitor (SC_s) despite their potential currently exhibit energy density levels that fall short of the necessary threshold for long-term applications. This limitation primarily stems from the challenge of identifying the ideal materials to enhance their performance. However, transition metal tellurides have a well-studied group of materials that have garnered noticeable consideration because of high energy density. Herein, we present a novel hydrothermal method that involves the fabrication of reduced graphene oxide (rGO) nanosheet combined with niobium telluride (NbTe₂) material. However, the NbTe₂@rGO nanohybrid's specific capacitance (C_sp) was 1475 F g⁻¹, which was approximately twice as high as the specific capacitance of the NbTe₂ (667 F g⁻¹) electrode with a specific capacity of 826 C/g at 1 A g⁻¹ which could be ascribed to interconnection between nanoparticles and nanosheets in the NbTe₂@rGO nanohybrid with lower R_ct = 0.02 Ω and outstanding cycling stability even after undergoing 7000th cycles with a capacitance retention of (97 %). The NbTe₂@rGO nanohybrid demonstrated an impressive power density of 285 W kg⁻¹ and energy density of 22 Wh kg⁻¹ at 1 A g⁻¹ in its symmetric two-electrode performance. The findings of this investigation suggested that NbTe₂@rGO nanohybrid exhibits promising material for future energy storing devices.