Highly Dispersed Antimony–Bismuth Alloy Encapsulated in Carbon Nanofibers for Ultrastable K-Ion Batteries

Abstract

Antimony-based alloys have appealed to an ever-increasing interest for potassium ion storage due to their high theoretical capacity and safe voltage. However, sluggish kinetics and the large radius of K+ lead to limited rate performance and severe capacity fading. In this Letter, highly dispersed antimony–bismuth alloy nanoparticles confined in carbon fibers are fabricated through an electrospinning technology followed by heat treatment. The BiSb nanoparticles are uniformly confined into the carbon fibers, which facilitate rapid electron transport and inhibit the volume change during cycling owing to the synergistic effect of the BiSb alloy and carbon confinement engineering. Furthermore, the effect of a potassium bis­(fluorosulfonyl)­imide (KFSI) electrolyte with different concentrations has been investigated. Theoretical calculation demonstrates that the incorporation of Bi metal is favorable for potassium adsorption. The combination of delicate nanofiber morphology and electrolyte chemistry endows the fiber composite with an improved reversible capacity of 274.4 mAh g–1, promising rate capability, and cycling stability upon 500 cycles.

Electrospun carbon-based nanomaterials for next-generation potassium batteries

“…9e), BiSb NPs embedded in CNFs (BiSb@CNFs) were fabricated via electrospinning. 149 Fig. 9f shows that BiSb NPs with a diameter of around 100–150 nm encapsulated in CNFs can alleviate the volume change of the BiSb alloy.…”

“…Reproduced with permission. 149 Copyright 2022, American Chemical Society. In situ TEM characterization of red P@N-PHCNFs during the potassiation process.…”

Facile synthesis of BiSb/C composite anodes for high‐performance and long‐life lithium‐ion batteries

“…Herein, we have successfully synthesized BiSb/C composites from relatively cheap commercially available microsized Bi, Sb, and graphite via simple, low‐cost, and efficient high‐energy mechanical milling (HEMM) process for high‐capacity and long‐cycle life LIBs. Bi and Sb can form bimetallic alloys at any molar ratio, providing the possibility of compositional control for high electrochemical performance 43–46 . Compositing Sb with Bi (specific capacity of ∼385 mAh g –1 : Li 3 Bi, high volumetric capacity of ∼3800 mAh cm –3 , and volume change of ∼215%) 47–49 through the ball‐milling could be an effective way to partly address the issues associated with the large volume changes of pristine Sb and Bi.…”

A Self-Stratified Thermally Regenerative Battery Using Nanoprism Cu Covering Ni Electrodes for Low-Grade Waste Heat Recovery

“…Benefiting from the nanoprism Cu layer, the large electrode surface area is promising to promote the charging reaction kinetics of anodic reaction , (Figure (a)). LSV tests were used to focus the reaction rates of Cu and NH 3 on Cu foam and NP Cu@Ni.…”

“…To confirm this feature and get the characterization details, the cathode electrodes after discharge under a constant current density of 25 mA cm −2 were obtained and investigated using TEM and XRD tests. The crystal structure of the original and self-restored electrodes was further characterized by HR-TEM observations as shown in Figure 3 Benefiting from the nanoprism Cu layer, the large electrode surface area is promising to promote the charging reaction kinetics of anodic reaction 30,31 (Figure 4(a)). LSV tests were used to focus the reaction rates of Cu and NH 3 on Cu foam and NP Cu@Ni.…”