Comparative Study of Bimetallic Cu/Co MOF Synthesis Strategies and Their Electrochemical Features

Abstract

In this work, three distinct synthetic procedures—step-by-step (CC-1), single-step (CC-2), and simple mixing (CC-3)—were utilized to investigate their effects on the formation of heterostructures in bimetallic Cu/Co-MOFs. The resulting MOF crystal structure reveals a 1:1 ratio of Co to Cu metal ions, and it was evaluated using the above two strategies and compared this electrochemical activity with a simple mixture of individual MOFs, forming a heterojunction. To maximize the benefits of this synthesis approach for supercapacitor uses, electrochemical analyses were conducted. These analyses revealed a capacitance of CC-1 is 438 F/g at 1 A/g, which is 1.14 times that of CC-2 and 2.76 times higher than the CC-3 samples. The notable performance is endosed to the synergistic contributions from each 2D material component and the formation of a stable heterostructure, owing to the optimal metal ion loading. The best-performing CC-1 electrode was further tested in both asymmetric (AD) and symmetric (SD) coin cell devices. The AD demonstrated an energy density (ED) of 40.4 Wh/kg through a power density (PD) of 302.3 W/kg with 75% steadiness, while the SD displayed an ED of 15.7 Wh/kg and a PD of 346.7 W/kg by 88% stability.