Molecular Regulation on Carbonyl-Based Organic Cathodes: Toward High-Rate and Long-Lifespan Potassium–Organic Batteries

Abstract

Organic redox-active molecules have been identified as promising cathodes for practical usage of potassium-ion batteries (PIBs) but still struggle with serious dissolution problems and sluggish kinetic properties. Herein, we propose a pseudocapacitance-dominated novel insoluble carbonyl-based cathode, [2,6-di­[1-(perylene-3,4,9,10-tetracarboxydiimide)]­anthraquinone, AQ–diPTCDI], which possesses high reversible capacities of 150 mAh g–1, excellent cycle stability with capacity retention of 88% over 2000 cycles, and fast kinetic properties. The strong intermolecular interactions of AQ–diPTCDI and in situ formed cathode electrolyte interphase films support it against the dissolution problem. The high capacitive-like contribution in capacities and fast potassium-ion diffusion enhance its reaction kinetics. Moreover, a symmetric organic potassium-ion battery (OPIB) based on AQ–diPTCDI electrodes also exhibits outstanding K-storage capability. These results suggest that AQ–diPTCDI is a promising organic cathode for OPIBs and provide a practicable route to realize high-performance K storage.

Ultrastable Bioderived Organic Anode Induced by Synergistic Coupling of Binder/Carbon-Network for Advanced Potassium-Ion Storage

“…The 1st and 10th curves of the J@CNT-SA electrode almost overlap at a high frequency (Figure S12; the donation from SEI layers), indicating that the R SEI values are almost stable during cycling and the formation of a stable SEI film. 51 Although the J@CNT-SA electrodes show a high R ct value in the first cycle, the small increase in R ct after 10 cycles indicates a good reversibility of the electrode, which is also reflected in the σ (Warburg coefficient) value (Figure 4i and Table S2).…”

A Facile Strategy for Synthesizing Organic Tannic Metal Salts as Advanced Energy Storage Anodes

“…The irreversible reduction peak around 0.65 V shows that SEI film was also formed on the electrode surface. In the subsequent cycles, the cathode peak at 0.98 V gradually shifted to 0.78 V, synchronously, and the anode peak gradually shifted from 1.05 to 0.84 V. The lower symmetry of the peak indicated a reduction in the reversibility of the redox reaction, which may cause a loss of capacity [48] . And it changed more slowly in the next number of cycles, exhibiting that it tended to more stable after the first several cycles [49] .…”

“…In the subsequent cycles, the cathode peak at 0.98 V gradually shifted to 0.78 V, synchronously, and the anode peak gradually shifted from 1.05 to 0.84 V. The lower symmetry of the peak indicated a reduction in the reversibility of the redox reaction, which may cause a loss of capacity. [48] And it changed more slowly in the next number of cycles, exhibiting that it tended to more stable after the first several cycles. [49] Figure 2c and 2d display the first five discharge and charge profiles of LiTA and NaTA, respectively.…”

Molecular structure design of planar zwitterionic polymer electrode materials for all-organic symmetric batteries

“…S16-S18 †) and the TEM images of the cycled PSQ anode (Figure S19 †) show the compact electrode surface, which might be attributed to the development of a solid electrolyte interface (SEI). 58,60,61 The SEI film might be helpful for inhibiting the dissolution of organic materials in the electrolyte and protecting them from being affected by electrochemical byproducts such as HF, thus being conducive to their long-term cycling stability.…”