Boosted crystalline/amorphous Fe2O3-δ core/shell heterostructure for flexible solid-state pseudocapacitors in large scale

Sun, Shuo; Zhai, Teng; Liang, Chaolun; Savilov, S. V.; Xia, Hui

doi:10.1016/j.nanoen.2018.01.015

Cited by 249 publications

(142 citation statements)

References 43 publications

Supporting

Mentioning

135

Contrasting

Order By: Relevance

“…Generally, SCs are divided into two categories; one, referred to as electric double‐layer capacitors (EDLCs), is based on the accumulation of electrolyte ions near the surface of electrode materials in the form of electrical double layer (EDL), and the other one, referred to as pseudo‐capacitor, involves “reversible” Faradic reaction and is mainly based on either metal oxides or conductive polymers . Recently, there has been great interest in pseudo‐capacitors due to their relatively higher Faradic capacitances than EDLCs .…”

Section: Introductionmentioning

confidence: 99%

High‐performance activated carbons for electrochemical double layer capacitors: Effects of morphology and porous structures

et al. 2019

View full text Add to dashboard Cite

Summary In this work, we prepare a series of activated carbons (ACs) from xylose with different combinations of hydrothermal synthesis (HTS) and chemical activation with KOH. The prepared ACs exhibit a variety of morphologies and porous structures, which depend on the conditions used in the hydrothermal synthesis and the chemical activation. The largest surface area (SBET) of the prepared ACs, which is calculated by the Brunauere Emmette Teller (BET) method, is ~3500 m2/g, and the largest volume fraction of mesopores of the prepared ACs is 60%. The correlations between the specific electrochemical properties of the ACs and the structures of the ACs (ie, porous structures and morphologies) are discussed. Spherical ACs exhibit superior rate performance with low impedance. The ACs with three‐dimensional interconnected network of large surface area and porosity possess high specific capacitance. The largest specific capacitance reaches 340 F/g at a current density of 0.5 A/g and 220 F/g at a current density of 50 A/g, which are superior or comparable to those of similar systems. The long‐term capacitance retention is ~86.8% after 10 000 cycles at a current density of 50 A/g. The energy density reaches 48 Wh/kg at a power density of 13.6 kW/kg.

show abstract

Section: Introductionmentioning

confidence: 99%

High‐performance activated carbons for electrochemical double layer capacitors: Effects of morphology and porous structures

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Although Fe 2+ ions do not directly interact with the absorption, they affect the adsorption of Fe 3+ ions through super exchange coupling. The lower peak intensity of N‐Fe 2 O 3− x /CC suggests a high concentration of Fe 2+ dopant as compared to A‐Fe 2 O 3 /CC . With no doubts, this doping of low‐valent iron would enhance the concentration of charge carriers and thus the electrical conductivity, as confirmed by the Mott−Schottky plot (Figure S5, Supporting Information) and linear sweep voltammetry (Figure S6, Supporting Information).…”

Section: Resultsmentioning

confidence: 87%

Dual‐Doped Hematite Nanorod Arrays on Carbon Cloth as a Robust and Flexible Sodium Anode

Sun

Wang

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

Rechargeable batteries with flexibility can find tremendous applications in wearable and bendable electronics. One central mission for the advancement of such high‐performance batteries is the exploration of flexible anodes with electrochemical and mechanical robustness. Herein reported is a robust and flexible sodium‐ion anode based on self‐supported hematite nanoarray grown on carbon cloth. The ammonia treatment that results in dual doping of both nitrogen and low‐valent iron renders surface reactivity and electric conductivity to the material. The dual‐doped hematite arrays afford a robust activity for sodium storage, exhibiting reversible capacities of 895 and 382 mAh g−1 at current rates of 0.1 and 5 A g−1, respectively, or 615 and 356 mAh g−1 by removing the contribution of the substrate. They also sustain 85% of the initial capacity upon 200 cycles at 0.2 A g−1. To demonstrate the flexibility, full cells composed of a hematite array anode and Na3V2(PO4)3/C cathode are assembled. The cell is capable of affording an energy density of 201 Wh kg−1 and sustaining repeated bending without performance decay, demonstrating a significant potential in practical application.

show abstract

“…Moreover, the NP c‐V 2 O 3 /r‐VO 2‐x also outperforms some of the best pseudocapacitive electrodes in previous reports. Similarly, Xia and his co‐workers developed a unique crystalline core/amorphous shell heterostructure at near‐surface of Fe 2 O 3 nanorods through a simple room‐temperature treatment in NaBH 4 solution (denoted as ASV‐FO; Figure a) . The thickness of the amorphous layer in ASV‐FO could be easily tuned from 1 to 5 nm by varying the NaBH 4 concentrations, which is beneficial to the Li + mobility in ASV‐FO (7c).…”

Section: Recently Emerging Approaches For Surface Engineeringmentioning

confidence: 99%

“…Similarly, Xia and his co-workers developed a unique crystalline core/amorphous shell heterostructure at near-surface of Fe 2 O 3 nanorods through a simple room-temperature treatment in NaBH 4 solution (denoted as ASV-FO; Figure 7a). [63] The thickness of the amorphous layer in ASV-FO could be easily tuned from 1 to 5 nm by varying the NaBH 4 concentrations, which is beneficial to the Li + mobility in ASV-FO (7c). As schematically illustrated in Figure 7d, the amorphous surface layer on Fe 2 O 3 nanorods generated through a facile NaBH 4 treatment at room temperature not only can facilitate the Li + diffusion at the electrode surface but also induce the crystalline/amorphous heterostructure to serve as extra Li + storage sites, leading to enhanced charge storage capability.…”

Section: Heterostructure Around Surfacementioning

confidence: 99%

Surface Engineering for Advanced Aqueous Supercapacitors: A Review

Yang

et al. 2019

ChemElectroChem

View full text Add to dashboard Cite

Considerable attention has been focused on aqueous supercapacitors (SCs), owing to their large power density and excellent cycling stability, which makes them more suitable for high power applications. However, the lower energy densities (E) of aqueous SCs as compared to batteries have impeded their range of commercial applications. To overcome this challenge, intensive studies have been devoted to the topic, in which surface engineering becomes critical to the high‐performance electrode design due to the efficient manipulation of a material surface to boost energy storage while maintaining the integrity of interior of the material. The purpose of this Minireview article is to highlight recent significant breakthroughs realized through surface engineering approaches such as surface functionalization, heterostructure design, and surface charge modulation. Current challenges, emerging trends, and opportunities for advanced SCs are discussed accordingly.

show abstract

Boosted crystalline/amorphous Fe2O3-δ core/shell heterostructure for flexible solid-state pseudocapacitors in large scale

Cited by 249 publications

References 43 publications

High‐performance activated carbons for electrochemical double layer capacitors: Effects of morphology and porous structures

High‐performance activated carbons for electrochemical double layer capacitors: Effects of morphology and porous structures

Dual‐Doped Hematite Nanorod Arrays on Carbon Cloth as a Robust and Flexible Sodium Anode

Surface Engineering for Advanced Aqueous Supercapacitors: A Review

Contact Info

Product

Resources

About