MWCNT-mesoporous silica nanocomposites inserted in a polyhedral metal–organic framework as an advanced hybrid material for energy storage device

Abstract

Here, three different materials were prepared containing high-conductivity multi-walled carbon nanotubes (MWCNTs), a high power density of mesoporous ordered silica SBA-15 (due to the high specific surface area), and nanoporous walls to improve the energy and power densities of energy storage devices. Thus, a hybrid composite of SBA-15 and MWCNTs was fabricated. The new composite of SBA-15/CNTs was decorated with a tri-metal organic framework, NiCoCu-BTC (1,3,5-benzenetricarboxylic acid, H₃BTC), via a simple, low-cost, and one-step solvothermal method. The structural features of the prepared nanomaterial play a key role in increasing the number of active sites and accelerating ion/electron transfer. Also, the trimetallic organic framework (due to its different oxidation states) provides richer redox reactions than monometallic and bimetallic ones to produce a high energy density material. This nanocomposite was used as an efficient electrode material in the fabrication of high-performance supercapacitors. The prepared nanocomposite demonstrated excellent electrochemical performance with a high specific capacity of 868 C g⁻¹ (2067 F g⁻¹) at a current density of 1.0 A g⁻¹, good rate capability (563 C g⁻¹ at 10 A g⁻¹), and high cycling durability. The excellent electrochemical performance of SC@NCC-BTC suggests that this composite is a promising candidate for energy storage applications.