Confine, Defect, and Interface Manipulation of Fe₃Se₄/3D Graphene Targeting Fast and Stable Potassium‐Ion Storage

Abstract

The fast electrochemical kinetics behavior and long cycling life have been the goals in developing anode materials for potassium ion batteries (PIBs). On account of high electron conductivity and theoretical capacity, transition metal selenides have been deemed as one of the promising anode materials for PIBs. Herein, a systematic structural manipulation strategy, pertaining to the confine of Fe3Se4 particles by 3D graphene and the dual phosphorus (P) doping to the Fe3Se4/3DG (DP‐Fe3Se4/3DG), has been proposed to fulfill the efficient potassium‐ion (K‐ion) evolution kinetics and thus boost the K‐ion storage performance. The theoretical calculation results demonstrate that the well‐designed dual P doping interface can effectively promote K‐ion adsorption behavior and provide a low energy barrier for K‐ion diffusion. The insertion‐conversion and adsorption mechanism for multi potassium storage behavior in DP‐Fe3Se4/3DG composite has been also deciphered by combining the in situ/ex situ X‐ray diffraction and operando Raman spectra evidences. As expected, the DP‐Fe3Se4/3DG anode exhibits superior rate capability (120.2 mA h g−1 at 10 A g−1) and outstanding cycling performance (157.9 mA h g−1 after 1000 cycles at 5 A g−1).

Free-Standing Carbon Nanofiber Composite Networks Derived from Bacterial Cellulose and Polypyrrole for Ultrastable Potassium-Ion Batteries

“…53 The experimental results are further verified by firstprinciples calculations based on DFT, which constitutes a The optimized geometry structures with a single K atom in each model were acquired by the calculation of adsorption energy (ΔE a ). 54 The adsorption energy of the pristine C model with a single K atom was calculated as −1.16 eV, and the ΔE a of the undoped with carbon defect model was −2.27 eV. This indicates that K-adsorption ability of the defected carbon is higher than that if the pristine carbon.…”

“…The pristine C model of C-BC, undoped with carbon defect model, and N-doped with carbon defect model of C-BC@PPy were employed to differentiate the defect and doping effects on the K-adsorption ability (Figure f–h). The optimized geometry structures with a single K atom in each model were acquired by the calculation of adsorption energy (Δ E a ) . The adsorption energy of the pristine C model with a single K atom was calculated as −1.16 eV, and the Δ E a of the undoped with carbon defect model was −2.27 eV.…”

Prussian blue-derived multiple yolk–single shell-structured Se-doped Fe7S8@NC@C microcube composites as high-rate anodes for sodium-ion batteries

“…[3][4][5] As is known, sodium has more abundant resources and a higher standard electrode potential than lithium; meanwhile Na + ions and Li + ions have very similar physicochemical properties, so SIBs have much lower costs and higher safety compared to LIBs, making them an outstanding contender for new and emerging energy materials. [6][7][8] However, the larger radius and higher atomic mass of Na + compared with Li + result in inferior reaction kinetics in electrode materials, so their capacity and energy density are unsatisfactory. 9 Therefore, the development of high-performance SIBs has become a current frontier topic in the area of energy storage systems.…”

Multielement Co-Doped Carbon Derived from Spent LIBs Boosts Potassium Storage

“…Furthermore, existing fabrication methods are insufficient to meet the application requirements for abundant energy storage devices such as potassium/sodium-ion batteries. 20,21 Here, we innovatively propose a direct conversion strategy from the waste layered cathode material to porous energy carbon materials. The conventional separation and purification procedures are streamlined by the regeneration method, which also makes them flexible and economical.…”

“…These materials have opened up new opportunities due to their adjustable surface area and rich porosity characteristics, strong adsorption capacity, and great chemical and thermal stability. − However, the high cost of their complex synthesis, along with severe and energy-intensive testing conditions, has always been major concerns. Furthermore, existing fabrication methods are insufficient to meet the application requirements for abundant energy storage devices such as potassium/sodium-ion batteries. , …”