Integrating metal oxides and carbon materials holds significant potential for enhancing the energy and power densities of supercapacitors. However, designing and fabricating these composite materials at scale remains challenging. Here, we present a fast, scalable, one-pot hydrodynamic synthesis method to prepare ion-conductive and defect-free graphene from graphite and MnO2/graphene nanocomposites. Utilizing Taylor–Couette flow, this method efficiently shear-exfoliates graphite into large quantities of high-quality graphene sheets. MnO2 is then deposited on the graphene in a fluidic reactor within 10 minutes. The resulting MnO2/graphene nanocomposite demonstrates outstanding electrochemical performance, including a high specific capacitance of 679 F/g at 25 mV/s, a high rate capability with 74.7% retention at 1000 mV/s, and excellent cycling stability (∼94.7% retention over 20,000 cycles). An asymmetric supercapacitor device, with a graphene anode and MnO2/graphene cathode, achieves high energy (35.2 W h/kg) and power (7.4 kW/kg) densities, with high rate capability and long cycle life. – Journal cover design by scapiens
[Scientific Journal cover design] Low-Thermal-Budget Fluorite-Structure Ferroelectrics for Future Electronic Device Applications
In article number 2100028, Jiyoung Kim, Si Joon Kim, and their team review key factors involved in developing fluorite-structure ferroelectrics
