Compact Coupled Graphene and Porous Polyaryltriazine‐Derived Frameworks as High Performance Cathodes for Lithium‐Ion Batteries

Abstract

It is highly desirable to develop electroactive organic materials and their derivatives as green alternatives of cathodes for sustainable and cost-effective lithium-ion batteries (LIBs) in energy storage fields. Herein, compact two-dimensional coupled graphene and porous polyaryltriazine-derived frameworks with tailormade pore structures are fabricated by using various molecular building blocks under ionothermal conditions. The porous nanosheets display nanoscale thickness, high specific surface area, and strong coupling of electroactive polyaryltriazine-derived frameworks with graphene. All these features make it possible to efficiently depress the dissolution of redox moieties in electrolytes and to boost the electrical conductivity of whole electrode. When employed as a cathode in LIBs, the two-dimensional porous nanosheets exhibit outstanding cycle stability of 395 mAh g(-1) at 5 A g(-1) for more than 5100 cycles and excellent rate capability of 135 mAh g(-1) at a high current density of 15 A g(-1).

Asphalt‐Derived Hierarchically Porous Carbon with Superior Electrode Properties for Capacitive Storage Devices

“…Meanwhile, the 2D peak is more obvious and sharpened for HPC, and can be divided into three peaks (inset of Figure c), which is on behalf of the highly graphitized sheet of approximately three layers, as previously depicted in the HRTEM and AFM picture (Figure f). The broad peak at low‐angle region (around 25) in the XRD pattern indicating the amorphous feature of MPC . The broad peak disappears and an obvious peak occurs in the high‐angle region (around 43), demonstrating the graphitization of HPC (Figure d).…”

High Capacitive Storage Performance of Sulfur and Nitrogen Codoped Mesoporous Graphene

“…The peaks located at around1 65 and 400 eV correspond to S2pa nd N1s, respectively,i nt he XPS survey spectrum ( Figure 3d). [28] Therefore, the quasi-rectangular CV curve of the SNMG cathode is composed of both Li + adsorption/desorption and redox reactionp rocesses (Figure 5c). As shown in Figure3e, the high-resolution S2ps pectrum of SNMG reveals the presence of thiophene-S species( 164.3 and 165.5 eV).…”

“…As shown in Figure3e, the high-resolution S2ps pectrum of SNMG reveals the presence of thiophene-S species( 164.3 and 165.5 eV). [28,29] Commercial Li 4 Ti 5 O 12 (LTO) was used as the anode materialf or the LIHC because of good insertion and extraction properties of Li. [18,19] As ymmetric supercapacitor was fabricated to evaluate the double-layer capacitive properties, with a6mol L À1 solution of KOH as the electrolyte.…”

Polymer/Graphene Hybrids for Advanced Energy‐Conversion and ‐Storage Materials

“…The obtained composites show small resistance for the reaction with lithium ions, which leads to high capacity during the charge/discharge process. The LIB system is still able to retain 82 % of the initial capacity after 150 charge/discharge cycles at 0.5 C. Feng and co‐workers have prepared compact 2D coupled graphene/porous polyaryltriazine‐derived frameworks as a LIB cathode material. The prepared LIB system shows an excellent cycle stability of 395 mA h g −1 at 5 A g −1 for 5100 cycles and outstanding rate capability of 135 mA h g −1 at a high current density of 15 A g −1 , which exceeds that of previously reported cathode materials.…”