Surface Redox-Active Organosulfur-Tethered Carbon Nanotubes for High Power and Long Cyclability of Na–Organosulfur Hybrid Energy Storage

Abstract

Despite the clear benefits of Na and S active materials, Na− S hybrid energy storage devices have yet to be exploited, and existing Na−S batteries cannot provide fast kinetics and long-term stability. Herein, we describe chemical and electronic coupling of the redox-active organosulfur moiety (−S−S−S−) with carbon nanotube (CNT) networks for high power and long cyclability of Na−organosulfur hybrid energy storage devices. The facile and reversible surface redox kinetics of organosulfur-tethered CNT is associated with a two-electron transfer toward the formation of low-order polysulfide, as confirmed by in situ and ex situ analyses. The specific capacitance of SOS-OCNT is 377 F g −1 (94% of theoretical capacitance) and 61.3% of capacitance is retained at 10 A g −1 . The Na−organosulfur hybrid full cells deliver an ultrahigh power density of 13.4 kW kg −1 and high energy density of 27 Wh kg −1 over 50000 cycles.

Mesoporous Yolk‐Shell Structured Organosulfur Nanotubes with Abundant Internal Joints for High‐Performance Lithium–Sulfur Batteries by Kinetics Acceleration

“…In the charging process, the CS and SS bonds almost recover to their previous states (Figure 5b), indicating the highly reversible reaction process of SC@A. [33] However, the Li 2 S peak cannot totally disappear after the charging process (Figure 5c and Figure S22, Supporting Information). A little anchored Li 2 S in the organic framework may serve as interlayer support pillar and benefit the insertion/ desertion of lithium ions, reducing the reaction barrier of subsequent cycles.…”

“…The high-resolution C 1s spectrum of C@A can be deconvoluted to five C species: C sp 2 , C sp 3 , CO, CN, and CO, while SC@A has a new C-S peak (Figure S6, Supporting Information). [33] The S 2p spectrum of SC@A is similar to that of sulfur element with S 2p 1/2 and S 2p 3/2 peaks (Figure 2b), but these two peaks of SC@A red shift to 163.9 and 162.8 eV, respectively, indicating the covalent link of sulfur chains to C@A. [34,35] Besides, the peak at 161.4 eV is assigned to COS group, which may participate in the activation process of the first discharge.…”

“…As shown in the survey XPS spectra (FigureS5, Supporting Information), both C@A and SC@A compounds are composed of C 1s, N 1s, and O 1s peaks, while S 2s and S 2p peaks are only present in SC@A. The high-resolution C 1s spectrum of C@A can be deconvoluted to five C species: C sp 2 , C sp 3 , CO, CN, and CO, while SC@A has a new C-S peak (FigureS6, Supporting Information) [33]. The S 2p spectrum of SC@A is similar to that of sulfur element with S 2p 1/2 and S 2p 3/2 peaks (Figure2b), but these two peaks of SC@A red shift to 163.9 and 162.8 eV, respectively, indicating the covalent link of sulfur chains to C@A [34,35].…”

Electrolytes/Interphases: Enabling Distinguishable Sulfur Redox Processes in Room‐Temperature Sodium‐Sulfur Batteries

“…Besides, organic sulfur in carbonate ester electrolyte is also promising for Na storage utilization, but the number of research is very limited. [ 57 ]…”

Flexible sodium-ion capacitors boosted by high electrochemically-reactive and structurally-stable Sb2S3 nanowire/Ti3C2Tx MXene film anodes

“…Hybrid ion capacitors are promising candidates since they inherit the high energy density from the intercalation mechanism of batteries and the high-power characteristics from supercapacitors [3,4]. Although lithium-ion capacitors using graphite or lithium titanate/active carbon electrodes have been commercialized, the limited lithium reserves and extensive use of energy storage devices justify the substitution of lithium with abundant and cheap sodium [5][6][7][8][9]. Consequently, research has emerged on flexible sodium-ion capacitors (SICs) capable of storing appreciable electricity that can be discharged and charged at exceptionally high rate [10][11][12].…”