Ternary nanocomposite of TiO2-ZnO/MCM-41: synthesis and electrochemical performance in supercapacitors

Abstract

The development of composite materials in nano-scale for electrochemical activity has remained an enormous challenge in the supercapacitors (SCs) arena. In this work, a new type of ternary TiO2-ZnO/MCM-41 nanocomposite was designed and prepared for further improvement to the electrochemical performance. First, mesoporous MCM-41 silica material was prepared with a sol-gel method and then calcinate under 550 °C to form porous material. Subsequently, ZnO-TiO2 crystals were grown on the MCM-41 silica material surface via a solvothermal method to obtain ternary nanocomposite. The morphology and structure features of the ternary nanocomposite were investigated with FESEM, TEM, and AFM. From the BET analysis, the specific surface area (SSA) of the nanocomposite obtained 580 m2·g−1, which provided an excellent platform for the transmission of ions and electrons. After that, energy storage performance was evaluated by electrochemical measurements such as cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and electrochemical impedance spectroscopy (EIS). The electrochemical performance measurements demonstrate a specific capacitance (Cs) as high as 642.4 F·g−1. Moreover, it exhibits excellent cyclic stability with 98.7% capacitance retention after 5000 cycles, which is beyond that of most of the reported silica-based SCs. The current study provided a rational design and synthesis of multifunctional catalysts for the development of SCs applications.