A polymer-direct-intercalation strategy for MoS2/carbon-derived heteroaerogels with ultrahigh pseudocapacitance

Abstract

The intercalation strategy has become crucial for 2D layered materials to achieve desirable properties, however, the intercalated guests are often limited to metal ions or small molecules. Here, we develop a simple, mild and efficient polymer-direct-intercalation strategy that different polymers (polyethyleneimine and polyethylene glycol) can directly intercalate into the MoS2 interlayers, forming MoS2-polymer composites and interlayer-expanded MoS2/carbon heteroaerogels after carbonization. The polymer-direct-intercalation behavior has been investigated by substantial characterizations and molecular dynamic calculations. The resulting composite heteroaerogels possess 3D conductive MoS2/C frameworks, expanded MoS2 interlayers (0.98 nm), high MoS2 contents (up to 74%) and high Mo valence (+6), beneficial to fast and stable charge transport and enhanced pseudocapacitive energy storage. Consequently, the typical MoS2/N-doped carbon heteroaerogels exhibit outstanding supercapacitor performance, such as ultrahigh capacitance, remarkable rate capability and excellent cycling stability. This study offers a new intercalation strategy which may be generally applicable to 2D materials for promising energy applications.

MoS2/carbon composites prepared by ball-milling and pyrolysis for the high-rate and stable anode of lithium ion capacitors

“…23 Nonetheless, the electrochemical performance of MoS 2 is subject to its terrible intrinsic conductivity and severe volume changes during cycles, which will bring about the pulverization of electrode and the failure of active materials. [24][25][26] Recently, there are some strategies, such as preparing nano-sized MoS 2 , 27,28 mixed with conductive carbon matrix, [29][30][31] and increasing the interlayer distance, 22,32 to compensate the above shortage. However, many above synthetic methods are complicated and difficult for scale production so that researchers are looking forward to nding simple and scalable ways to synthesizing MoS 2 -based anode materials with superior rate property and long cycle life.…”

Vanadium‐Incorporated Metallic (1‐T) Molybdenum Sulfide Nanoroses for High‐Energy‐Density Asymmetric Supercapacitors

“…Here, i is the current [mA] at a particular potential, is the scan rate [mV s −1 ], and a and b are the adjustable parameters. It is observed that MVS nanoroses follow the charge‐storage mechanism through pseudocapacitive intercalation ( b >0.5), thus assuring the contribution from both capacitive and faradaic currents, whereas battery‐like intercalation behavior was more prominent in MS with b <0.5. This was further confirmed by the increasing capacitive contribution with increasing scan rates (Figure d).…”

“…Consequently, the metallic 1T phase reveals more electroactive sites owing to the exposed basal plane in comparison with inactive basal planes of the semiconducting 2H phase . One of the best strategies to form the metallic phase is to intercalate guest species, such as Li + , H + , and K + , into the layers . However, when this strategy was adopted, maximum utilization for charge storage was not possible.…”

In‐situ formation and intercalation of carbon dots induced high‐yield 1T‐molybdenum disulfide as electrode materials

“…It can be seen that the typical (002) reflection peak disappeared and split into two different peaks at 9.0° and 16.6°, respectively. It probably attributes to the strong interaction and exploitation of CDs into the MoS 2 layers, so that expanding the spacing of MoS 2 nanolayers . The d‐spacing (002) of S4 hybrid was calculated to be 0.84 nm was higher than S0 (0.68 nm) according to the Scherer equation.…”