Porous carbon nanotubes etched by water steam for high-rate large-capacity lithium–sulfur batteries

Abstract

A simple, green, scalable one-step approach to obtain porous CNTs (PCNTs) with a high specific surface area and pore volume has been developed involving a mild chemical reaction between CNTs and rare oxygen sourced from nebulized water vapor at high temperatures.

Steam-Etched Spherical Carbon/Sulfur Composite with High Sulfur Capacity and Long Cycle Life for Li/S Battery Application

“…1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 During the positive scanning, the oxidation peak corresponds to the reaction from the solid Li 2 S and Li 2 S 2 to polysulfides and sulfur. [22][23][24]39 Comparing with KB-S, the A-KB-S shows higher reduction peak current and oxidation peak current, as well as higher onset reduction potential.…”

“…23,43 Firstly, water steam is absorbed into the pores of the carbon particles, and then reacts with carbon under high temperature. During this process, more abundant microand meso-pores are formed inside the carbon sphere after a series of carbon gasification reactions (Schematic 2), with CO, CO 2 and H 2 releasing.…”

“…Choi et al also developed many kinds of porous carbon materials with advanced Li/S battery performance. 6,12,[20][21][22][23][24][25][26][27][28][29][30][31][32][33] Carbon materials with controlled morphology and tunable pore structure have shown excellent performance. [34][35][36][37][38] However, most reported results on Li-S batteries are obtained from cathodes with a ''low sulfur content'' of only about 60 wt.…”

Improved performance of sulfur cathode by an easy and scale-up coating strategy

“…After the first cycle, the subsequent CV curves change slightly but overlap very well, which indicates good cycle stability. Moreover, the slight change between the first and second cycles of the CV curves is possibly related to the movement of the sulfur compounds from primary position to the stable location [29,33]. The CV curves of the pristine sulfur cathode is also obtained, as presented in Fig.…”

Coating of sulfur particles with manganese oxide nanowires as a cathode material in lithium–sulfur batteries

“…However, they have some drawbacks, e.g., the insulating nature of sulfur (5 Â 10 À 30 S cm cm À 1 at room temperature) and the dissolution of lithium polysulfides [3]. To resolve these issues, various studies have been performed with various carbons [4], polymer coatings [5], and metallic oxides [6]. Among these materials, metallic oxide is fascinating because it provides higher electrode density than carbon materials as well as comparable diffusion of Li þ in the structure.…”