A new rapid synthesis of hexagonal prism Zn-MOF as a precursor at room temperature for energy storage through pre-ionization strategy

Abstract

In this paper, a new hexagonal prismatic Zn-MOF is rapidly synthesized at room temperature through a one-step precipitation method as precursor for the preparation of porous carbon. The SEM and GCD tests indicate that the pre-ionization process of BTC greatly accelerates the reaction speed between BTC and Zn ions, and only 0.5 h is required for the preparation of Zn-MOF with orderly morphology at room temperature, far less than 3–24 h of the existing hydrothermal synthesis. The derived porous carbon (BTCC) is provided with a considerable specific surface area of 1,464 m2 g−1 and suitable pores of 3.9 nm in size. Its richly porous structure offers a superior supercapacitor performance. The BTCC electrode offered a high specific capacitance and an excellent cycle stability. Furthermore, the assembled two symmetrical supercapacitors, C|1 M Na2SO4|C and C|6 M KOH|C, provide high energy density of 22.4 Wh kg−1 and 13.7 Wh kg−1, respectively. Their energy retention rates were 80.0% and 89.4%, respectively after 10,000 cycles at 20 A g−1. The proposed pre-ionization strategy is a facile, convenient and easy-to-industrial method for the preparation of new MOFs, thereby significantly reducing the manufacturing cost of porous carbon for energy storage.