Using a Heme‐Based Nanozyme as Bifunctional Redox Mediator for Li−O₂ Batteries

Abstract

The realization of practical aprotic Li−O2 batteries is hindered by superoxide‐related parasitic reactions and high overpotentials. Herein, a heme‐based nanozyme containing iron‐porphyrin derivative ligands is used as a novel electrolyte additive to scavenge superoxide radicals in the Li−O2 system. Specially, this type of nanozyme can act as a bifunctional catalyst for both discharge and charge by coordinating with superoxide intermediates, functioning as a molecular shuttle of superoxide species and electrons between cathodes and products. As a consequence, the Li−O2 batteries exhibit boosted discharge capacity, reduced charge polarization and superior cycling stability in the presence of the nanozyme additive. This first attempt to using nanozyme in Li−O2 batteries should pave a new way for the sustainable cross‐link between biomimetic enzymes and advanced energy storage.

Trifunctional imidazolium bromide: a high-efficiency redox mediator for high-performance Li–O2 batteries

“…1b, the NBT solution with KO 2 and crown ether is changed to blue, which indicates that O 2 ˙ − is formed in the solution, and there is a wide peak at 560 nm in the ultraviolet-visible light (UV-vis) spectrum. 24 The absorbance intensity of the NBT solution decreases with increasing APMImBr concentration, verifying the adsorption of O 2 ˙ − by APMIm + . Therefore, the discharge capacity of the battery increases gradually with the increase of the APMImBr concentration (Fig.…”

Atomic engineering of single-atom nanozymes for enzyme-like catalysis

“…In addition, Mu et al recently reported that the addition of Zn-TCPP(Fe) nanozymes to Li-O 2 batteries would scavenge superoxide radicals, reduce the damage caused by aggressive superoxide intermediates, and improve the cycling stability. 112 The Zn-TCPP(Fe) nanozymes performed as an ORR/OER bifunctional catalyst and served as a molecular shuttle of superoxide species and electrons between cathodes and products in both discharge and recharge processes, leading to enlarged discharge capacity and elevated energy efficiency.…”

Metal‐Organic Framework‐Based Lithium‐Oxygen Batteries

“…Zhou's group designed a soluble Heme-based MOF as an electrolyte additive for LOBs. [32] This MOF was synthesized according to a surfactant-assisted method, as illustrated in Figure 7a. Specifically, the heme-like TCPP(Fe) ligands serve as catalytic active sites, metal nodes act as structure building blocks, and polyvinylpyrrolidone (PVP) is employed as a surfactant to control the growth of MOF crystals.…”

“…Zhou's group designed a soluble Heme‐based MOF as an electrolyte additive for LOBs [32] . This MOF was synthesized according to a surfactant‐assisted method, as illustrated in Figure 7a.…”