Inorganic–Organic Composite of FeOOH-GO-PEDOT with High Capacity for Lithium Storage

Transition metal oxides are critical components in lithium-ion batteries due to their high electrochemical activity, which allows them to efficiently store and release lithium ions during charge and discharge cycles. However, these materials often suffer from poor crystal structure stability, making them susceptible to structural changes that degrade cycling stability. To overcome this issue, in this study, a novel inorganic–organic composite is proposed and prepared. Graphene-coated FeOOH (FeOOH-GO) was synthesized through a solution blending reaction, followed by ultrasonic mixing with a Poly(3, 4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) aqueous solution to obtain an inorganic–organic composite, denoted as FeOOH-GO-PEDOT. The structural and electrochemical properties of the composite materials were characterized using techniques such as powder X-ray diffraction (XRD), scanning electron microscopy (SEM) with elemental mapping, and thermogravimetric differential thermal analysis (TG-DTA). The results demonstrated that the composite electrode, modified with 40% graphene and PEDOT:PSS, exhibited excellent electrochemical performance, with an initial charge/discharge capacity of 1766.4 mAh g–1. After 100 cycles at a current density of 0.5 C (1 C = 500 mA g–1), the discharge capacity was maintained at 1238.4 mAh g–1. This composite material also exhibited good rate performance (200 mAh g–1 at 5 C) and high cycle stability (capacity retention of 70% after 100 cycles at 1 C), with the enhanced electrochemical performance primarily attributed to the open, sheet-like staggered barrier structure.