Encapsulation of Iodine in Nitrogen-Containing Porous Carbon Plate Arrays on Carbon Fiber Cloth as a Freestanding Cathode for Lithium-Iodine Batteries

Abstract

Rechargeable lithium-iodine (Li-I2) batteries are a promising energy storage technology because of their cost-effectiveness and nature abundance of iodine. However, the low electron conductivity, slow diffusion kinetics, and poor stability of iodine are the big hindrances to the technology development. We report here an approach to improving iodine cathode performance by stabilizing iodine with polyvinylpyrrolidone (PVP) and porous nitrogen-containing carbon plate arrays (PNCA) grown on carbon fiber cloth. This freestanding composite electrode exhibits a charge storage capacity of 132 mA h g–1 at 5C and stable cycling stability (150 mA h g–1 after 1000 cycles at 1C). The cycling stability of the electrode is due to the confinement effect of PNCA and PVP via both physical and chemical forces. In situ Raman spectroscopy results suggest that the I3 –/I– redox couple is highly reversible during galvanostatic charge/discharge cycling. The pseudocapacitive lithium storage behavior of the composite electrode enables its high rate performance in Li-I2 batteries. This work provides a facile approach to designing freestanding cathode materials for high-rate and stable Li-I2 batteries.

Hydrogen‐Bonded Organic Framework for High‐Performance Lithium/Sodium‐Iodine Organic Batteries

“…The I 2 /HOF and I 2 /Ti 3 C 2 T x electrodes showed similar redox features (Figure S17). Typical electrochemical discharge/charge curves for the I 2 /HOF@Ti 3 C 2 T x electrode exhibit two symmetrical voltage plateaus, with discharge curves of 3.29–3.48 V and 2.55–2.94 V and charge curves of 3.34–3.55 V and 2.95–3.23 V, indicating its good reversibility (Figure 4c) [44–46] . The in‐situ XRD was conducted for Li‐I 2 batteries to investigate the electrochemical reaction mechanism of I 2 /HOF@Ti 3 C 2 T x (Figure S18).…”

“…Typical electrochemical discharge/charge curves for the I 2 / HOF@Ti 3 C 2 T x electrode exhibit two symmetrical voltage plateaus, with discharge curves of 3.29-3.48 V and 2.55-2.94 V and charge curves of 3.34-3.55 V and 2.95-3.23 V, indicating its good reversibility (Figure 4c). [44][45][46] The in-situ XRD was conducted for Li-I 2 batteries to investigate the electrochemical reaction mechanism of I 2 /HOF@Ti 3 C 2 T x (Figure S18). At the fully charged state (3.6 V), the diffraction peaks located at 24.0°, 24.6°, and 28.7°correspond to the characteristic peaks of I 2 (PDF#05-0558).…”

Iron anode‐based aqueous electrochemical energy storage devices: Recent advances and future perspectives

“…Besides nonmetal S (or extended chalcogens like Se and Te) cathodes, the elemental iodine (I 2 ) may also trigger great scientific enthusiasm in aqueous EES devices due to its abundance in ocean and eco-friendly nature, quick I 2 /Ireaction kinetics and considerable theoretical specific capacity (~211 mAh g −1 ). [114][115][116] However, some tough obstacles, including adverse I 2 disproportion/parasitic reactions in either alkaline or acidic aqueous solutions, and undesired shuttling effect of iodine species, still require addressing carefully. [117] These factors would deteriorate the capacity retention and other operation parameters, or even cause a sudden battery failure.…”

“…The alternative use of 3D anodes grown directly on conductive current collectors would not only simplify the electrode manufacturing and save the extra electrode additives, but also provide unique advantages including direct electron transport along specific direction, shortened ions diffusion pathways, more sufficient electrode-electrolyte contacting areas, and proper mechanical accommodation/release for strains induced by anodic phase transformation. [63,64,114,143,149,150] A recent typical example is the use of conformal surface coating strategy to design hybrid arrayed Fe 3 O 4 nanorods via atomic layer deposition (ALD) technique. [150] The resultant Fe 3 O 4 @TiO 2 core-shell nanorod arrays demonstrate the following inherent advantages (Figure 7C): (i) ALD technique ensures high uniformity and precise thickness control of TiO 2 shells, and their robust mechanical adhesion to Fe 3 O 4 ; (ii) the outer TiO 2 is a classic Li + intercalation anode with less volume change, capable of acting as a durable "armor" against volume expansion of inner Fe 3 O 4 nanorods during charging/discharging; (iii) the presence of TiO 2 shells contributes to additional capacity via Li + surface adsorption/desorption, and also partially suppresses the HER; (iv) straightforward alignment of individual nanorods onto current collectors enables direct electrons transfer and easy electrolytic penetration into entire electrode regions.…”

Long-Lasting Zinc–Iodine Batteries with Ultrahigh Areal Capacity and Boosted Rate Capability Enabled by Nickel Single-Atom Electrocatalysts

“…Moreover, NiSAs-HPC and HPC have high specific surface areas of 883.8 and 914.8 m 2 g –1 , respectively. It is notable that the large surface area and high pore volume can facilitate iodine infiltration, while the hierarchical micromesoporous structure strongly restricts the dissolution of intermediate polyiodides and further suppresses the induced shuttling. , …”