Silver-Intermediated Perovskite La_0.9FeO_3−δ toward High-Performance Cathode Catalysts for Nonaqueous Lithium–Oxygen Batteries

Abstract

Development of efficient cathode catalysts is crucial for achieving high-performance rechargeable lithium–oxygen batteries. Herein, a simple one-step electrospun method was applied to obtain a silver-modified perovskite La0.9FeO3−δ (Ag@LFO) as an efficient cathode catalyst. The synthesized catalyst has two characteristics: first, the doping of Ag led to a tailored electronic structure including the generation of Fe4+; second, the in situ grown Ag exhibits a stronger interaction with perovskite. These two advantages result in high oxygen adsorbability and increased percentage of highly active oxygen species. Therefore, film-like Li2O2 was observed during discharge on the Ag@LFO cathode, which is beneficial for decomposition during recharge, whereas Li2O2 generated on the LFO cathode was largely toroidal. Density functional theory calculations were used to discuss the Li2O2 growth mechanism. As a result, compared to La0.9FeO3−δ and post-loading silver-decorated La0.9FeO3−δ (Ag/LFO), Ag@LFO exhibits lower overpotential, improved rate-capability, higher discharge specific capacity, and especially promoted cycling performance that is triple that of LFO.

Halide Perovskite Materials for Energy Storage Applications

“…The halide perovskite materials could be extended to a range of secondary battery systems. The application of halide perovskites in various energy systems is promising, since the perovskite structures have been found applicable to a number of alkali-ion batteries, [241,242] lithium-sulfur batteries, lithiumoxygen batteries, [243][244][245][246][247][248][249][250][251][252][253][254][255][256] and zinc-air batteries. [257][258][259][260][261] Further deployment depends on the improvement of the halide perovskites stability when they are in contact with the salient species in the battery devices, such as the aqueous environment and basic/acidic electrolyte.…”

Cation‐Exchange‐Induced Metal and Alloy Dual‐Exsolution in Perovskite Ferrite Oxides Boosting the Performance of Li‐O2 Battery

“…Chemie ment of Fe atoms in LFCO and reduced LFCO.Asshown in Figure 3g,the spectra of LFCO and reduced LFCO were all well fitted by resolving into two sextets.The two sextets in all samples display an isomer shift (IS) in the range of 0.36-0.4 mm s À1 ,w hich are consistent with those reported for the high-spin Fe 3+ in octahedral coordination. [8,20] Thepresence of double sextet illustrated that Fe 3+ has two different coordination environments.I ti sw orth noting that the intensity of the first sextet (blue line) increased with the increase of reduction temperature,w hile the intensity of the second sextet (red line) performs the opposite trend (Figure 3g). We assumed that the first sextet is attributed to the Fe atoms surrounded by 6F ea toms via bridged oxygen bond (Fe-O-Fe), while the second sextet represents surrounding Fe atoms are partial replaced by Co atoms (Fe-O-Co), as shown in Figure 3d.T his is because in LFCO,C o 3+ shows ah igh-spin state,w hich affects the magnetic field of neighbor FeO 6 octahedral, leading to the spilled of sextet.…”

A renaissance of N,N-dimethylacetamide-based electrolytes to promote the cycling stability of Li–O2 batteries

“…The CV curve of the battery with 2 M LiTFSI and 1 M LiNO3 displays a typical Li-O2 battery behavior and shows the strongest anodic and cathodic peak intensities, indicating an improved ORR and OER kinetics. 35,36 The discharge and charge performance of the Li-O2 batteries without any cathode catalysts at a fixed specific capacity of 1000 mAh g -1 and a current density of 300 mA g -1 is then evaluated in Fig. 5b-d.…”