BIAN-based durable polymer metal complex as a cathode material for Li–O2 battery applications

Abstract

Among several strategies employed to reduce overpotential and achieve reliable reversibility with Li-O 2 batteries, the use of atomically dispersed bifunctional carbon catalysts is very attractive. However, most of the methods used to prepare these bifunctional oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) catalysts require high temperatures and exhibit low yields, and it is therefore difficult to predetermine the active sites qualitatively and quantitatively. Here, we propose the use of atomically dispersed metal centers coordinated to diimine moieties of conjugated polymers as bifunctional catalysts without further modification (pyrolysis or composite formation) for Li-O 2 battery applications. Poly(bisiminoacenaphthenequinone) (BIAN) iron complex (BP-Fe) catalysts showed high OER activities, which enabled 100% coulombic efficiency for 160 galvanostatic charge discharge cycles with a capacity limit of 500 mAh/g at a current density of 250 mA/g. The overpotential corresponding to charging was as low as ~1.0 V and exhibited almost no change in discharge overpotential across 160 cycles. Additionally, it showed a commendable rate capability with only a 170 mV increase in charge overpotential when the charge-discharge rate was increased from 100 to 500 mA/g.

Enabling Ultrafast Charging in Graphite Anodes Using BIAN-Based Conjugated Polymer/Lithium Polyacrylate as a Binder

“…The synthesis of the P-BIAN was performed using the procedure reported by Matsumi et al ,− The synthesis process of BIAN-LiPAA is shown in Figure . The synthesized polymer was successfully characterized via 1 H NMR and Fourier transform infrared (FT-IR) spectroscopy, and the results are shown in the Supporting Information.…”

“…Our previous studies have reported the robustness of BIAN-type conjugated polymer binders in graphite and Si-based anodes. ,− Structural highlights of the BIAN-type conjugated polymer binder are as follows: (a) the fused-planar naphthalene moiety of the polymer forms a π–π stacking interaction with the graphite skeleton, (b) the copper current collector clings to the diamine component of the polymer, allowing the binder to hold the electrode laminate intact on the current collector, and (c) the conjugated network of the polymer is provided by the BIAN-phenylene moiety as a component of the polymeric backbone, ensuring better electronic conductivity across the electrode matrix. , However, the Li + ion diffusion, R CT , and activation energy of lithiation of the anode can be further improved to enable XFC through additional binder design.…”

Design of Ir/Pt dual electrocatalysts loaded on exfoliated acetylene black for Li air battery application

“…FAB180-Pt/Ir 1:1 sample was chosen for CV measurements in nonaqueous medium, prior to air-battery test. It is important to thoroughly assess the catalyst's performance in a non-aqueous electrolyte beforehand [15,28]. CV for FAB180-Pt/Ir 1:1 measured in nonaqueous medium is shown in figure 8.…”

“…CV for FAB180-Pt/Ir 1:1 measured in nonaqueous medium is shown in figure 8. 0.1 M LiTFSI in TEGDME was used as nonaqueous electrolyte [28]. At the 50th cycle, the OER peak was not seen clearly around 1.41 V and ORR peak was seen in −1.75 V. After 100 cycles, change was seen around 1.21 V and −1.53 V. After 250 cycles the OER peak appeared more clearly.…”

“…The synergistic combination of ORR and OER processes is expected to improve the efficiency of oxygen-related reactions, resulting in reduced overpotential and increased cycle stability [27]. This approach holds promise for addressing the challenges associated with the formation and breakdown of Li x O 2 and improving the overall performance of Li-air batteries [28]. Following these, acetylene black has emerged as a promising choice for carbon-based supports in Li-air battery cathode catalysts due to its environmental friendliness, high stability, corrosion resistance, strong mechanical strength, and advantageous interaction with metal substrates [29].…”