Single-Atom Yttrium Engineering Janus Electrode for Rechargeable Na–S Batteries

Abstract

The development of rechargeable Na–S batteries is very promising, thanks to their considerably high energy density, abundance of elements, and low costs and yet faces the issues of sluggish redox kinetics of S species and the polysulfide shuttle effect as well as Na dendrite growth. Following the theory-guided prediction, the rare-earth metal yttrium (Y)–N4 unit has been screened as a favorable Janus site for the chemical affinity of polysulfides and their electrocatalytic conversion, as well as reversible uniform Na deposition. To this end, we adopt a metal–organic framework (MOF) to prepare a single-atom hybrid with Y single atoms being incorporated into the nitrogen-doped rhombododecahedron carbon host (Y SAs/NC), which features favorable Janus properties of sodiophilicity and sulfiphilicity and thus presents highly desired electrochemical performance when used as a host of the sodium anode and the sulfur cathode of a Na–S full cell. Impressively, the Na–S full cell is capable of delivering a high capacity of 822 mAh g–1 and shows superdurable cyclability (97.5% capacity retention over 1000 cycles at a high current density of 5 A g–1). The proof-of-concept three-dimensional (3D) printed batteries and the Na–S pouch cell validate the potential practical applications of such Na–S batteries, shedding light on the development of promising Na–S full cells for future application in energy storage or power batteries.

Manipulating the Spin State of Fe Sites via Fe–O–Si Bridge Bonds for Enhanced Polysulfide Redox Kinetics in the Li–S Battery

“…Furthermore, in situ Raman spectra are performed to monitor the LiPSs evolution mechanism. As illustrated in Figure 4e, for the FM-Hal/S cathode, the peaks of ∼150, ∼215, and ∼471 cm −1 can be attributed to the characteristic peaks of S 8 2− at 2.42 V. 31,49 The peaks of S 4 2− and S 6 2− (located at ∼199, ∼393, and ∼450 cm −1 ) appear during the following discharge process (2.26 V). Moreover, when the battery continues to discharge to 1.61 V, the intensity of S 4 2− and S 6 2− peaks decreases, while the new broad peak at ∼375 cm −1 corresponds to S 2…”

Defect engineering of two-dimensional materials for advanced energy conversion and storage

“…Particularly, similar to the Li-S batteries, the solubility of sodium polysulfides will lead to a severe shuttle effect. [439][440][441][442][443] Therefore, developing advanced S host materials is highly required to compete with traditional LIBs and Li-S batteries. To solve these problems, Bao et al reported an in situ S-doping approach for the fabrication of functionalized MXene nanosheets by introducing heteroatomic S into the precursor (Fig.…”

Recent advances of stimuli-responsive viologen-based nanocomposites

“…The investigation of MOFs is related to coordination chemistry, organic chemistry, inorganic chemistry, synthetic chemistry, etc., and displays extensive application prospects in detection, [43][44][45] adsorption and separation, [46][47][48] luminescence, 49-51 magnetism, 52,53 catalysis, 54,55 and energy storage. [56][57][58] Recently, bipyridine ligands that grafted substituents of nitrogenous oxygen ligands onto the bipyridine skeleton are successfully synthesized. Due to the excellent coordination ability of nitrogen and oxygen atoms, the modified bipyridine ligands are easily coordinated with metal ions or ion clusters.…”

“…, and displays extensive application prospects in detection, 43–45 adsorption and separation, 46–48 luminescence, 49–51 magnetism, 52,53 catalysis, 54,55 and energy storage. 56–58…”