Plasma Treatment for Nitrogen‐Doped 3D Graphene Framework by a Conductive Matrix with Sulfur for High‐Performance Li–S Batteries

Abstract

Lithium ion batteries (LIBs) are widely used storage devices, which have a wide range of applications in electrical devices, hybrid electric vehicles, and for harvesting of renewable energy. [1] However, increasing demands for high-performance energy storage are unlikely to be satisfied by the theoretical capacities of the LIBs. [2] In particular, alternative cathode materials are required. [3] Recently, lithium-sulfur (Li-S) batteries have received attention owing to their high theoretical specificCarbon materials have received considerable attention as host cathode materials for sulfur in lithium-sulfur batteries; N-doped carbon materials show particularly high electrocatalytic activity. Efforts are made to synthesize N-doped carbon materials by introducing nitrogen-rich sources followed by sintering or hydrothermal processes. In the present work, an in situ hollow cathode discharge plasma treatment method is used to prepare 3D porous frameworks based on N-doped graphene as a potential conductive matrix material. The resulting N-doped graphene is used to prepare a 3D porous framework with a S content of 90 wt% as a cathode in lithium-sulfur cells, which delivers a specific discharge capacity of 1186 mAh g −1 at 0.1 C, a coulombic efficiency of 96% after 200 cycles, and a capacity retention of 578 mAh g −1 at 1.0 C after 1000 cycles. The performance is attributed to the flexible 3D structure and clustering of pyridinic N-dopants in graphene. The N-doped graphene shows high electrochemical performance and the flexible 3D porous stable structure accommodates the considerable volume change of the active material during lithium insertion and extraction processes, improving the long-term electrochemical performance.

Three-Dimensional Carbon Nitride Nanowire Scaffold for Flexible Supercapacitors

“…Wearable energy storage devices, especially flexible supercapacitors, are getting extra attention due to their higher cycling stability and power density [1][2][3][4]. As for material systems of supercapacitor electrodes, recent researches mainly focus on three principle types: carbon-based high surface area materials (activated carbon, graphene, carbon fibers, and so on), transition metal oxides (MOs), and conducting polymers (CPs) [5][6][7][8].…”

N‐Doped graphene embellished with Co 9 S 8 enable advanced sulfur cathode for high‐performance lithium‐sulfur batteries

“…Recently, heteroatom‐doped carbon was developed as a sulfur‐supporting host material and exhibited a chemical interaction between heteroatom and LiPS in the process . However, in order to maintain the outstanding conductivity, the doping amount was kept low (less than 10%), thus limiting the amount of LiPS adsorption.…”

“…15,16 Recently, heteroatom-doped carbon was developed as a sulfur-supporting host material and exhibited a chemical interaction between heteroatom and LiPS in the process. [17][18][19][20][21][22][23] However, in order to maintain the outstanding conductivity, the doping amount was kept low (less than 10%), thus limiting the amount of LiPS adsorption. Simultaneously, it has been discovered that various transition metal sulfides with high polarities exhibited forceful chemisorption and excellent electrocatalysis, which availably alleviates the shuttle effect for Li-S cells.…”

Cobalt and nitrogen codoped carbon nanotubes derived from a graphitic C3N4 template as an electrocatalyst for the oxygen reduction reaction

“…The introduction of N atoms in carbon materials could signicantly enhance electrocatalytic activity, thus inducing efficient ORR. [15][16][17] In addition, previous reports have indicated that doping carbon materials with transition metals such as Co, Fe, Ni, etc. is also an effective way to improve the catalytic performance of the catalyst.…”