Fused Heteroaromatic Organic Compounds for High‐Power Electrodes of Rechargeable Lithium Batteries

Abstract

Organic redox compounds are emerging electrode materials for rechargeable lithium batteries. However, their electrically insulating nature plagues efficient charge transport within the electroactive bulk. Alternative to the popular solution of elaborating nanocomposite materials, herein we report on a molecular‐level engineering strategy towards high‐power organic electrode materials with multi‐electron reactions. Systematic comparisons of anthraquinone analogues incorporating fused heteroaromatic structures as cathode materials in rechargeable lithium batteries reveal that the judicious incorporation of heteroaromatics improves the cell performance in terms of specific gravimetric capacity, working potential, rate capability, and cyclability. Combination studies with morphological observation, electrochemical impedance characterization, and theoretical modeling provide insight into the advantage of heteroaromatic building blocks. In particular, benzofuro[5,6‐b]furan‐4,8‐dione (BFFD) bearing furan moeities shows a reversible capacity of 181 mAh g−1 when charged/discharged at 100C, corresponding to a power density of 29.8 kW kg−1. These results have pointed to a general design route of high‐rate organic electrode materials by rational functionalization of redox compounds with appropriate heteroaromatic units as versatile structural tools.

From an Enhanced Understanding to Commercially Viable Electrodes: The Case of PTCLi4 as Sustainable Organic Lithium‐Ion Anode Material

“…This sequence combined with MAS is referred to as the NQS/MAS experiment. [50] 1 H-13 C NMR correlation experiments: the 2D 1 H- 13 C HETCOR experiments were recorded at room temperature using a 4 mm Bruker CPMAS probe head on a Bruker AVANCE DSX 500 spectrometer operating at 125 MHz for the 13 C and at 500 MHz for 1 H. The data were collected with 80 complex data points in the 1 H indirect dimension and 4000 data points in the 13 C dimension. The corresponding spectral widths were 62 and 24 kHz, respectively.…”

“…[28] To differentiate between the types of carbon present in the studied systems, we have used a combination of variable cross-polarization (CP) and dipolar dephasing experiments. These were complemented by 13 C 1 H correlation experiments, which provide additional information regarding proton chemical shifts. Also, key in correctly assigning the experimental peaks is the insight brought by calculations using either semi-empirical methods or, as in the present case, more rigorous theoretical methods.…”

“…[9][10][11] In addition to their high availability, low cost, and environmental friendliness, organic active materials offer the distinguished advantage of tailorable lithium reaction potentials and capacities by carefully designing the molecular architecture. [9][10][11][12][13] In particular, the presence of planarly delocalized π-electrons, following the incorporation of phenyl groups in the units interconnecting the electrochemically active carbonyl functions, results in improved achievable capacities and Organic active materials are currently considered to be the most promising technology for the realization of fully sustainable secondary batteries. However, the understanding of the underlying reaction mechanisms is still at its beginning.…”

Recent Advances in the Use of Carbonyl Compounds as Active Components in Organic-Based Batteries

“…In recent years, several promising approaches for organic materialbased battery systems have been investigated [20][21][22], including extensive exploration of organic carbonyl compounds as high-energy cathode materials for rechargeable lithium batteries owing to their redox stability, structural diversity, high theoretical capacities, and infinite availability from biomass [23][24][25][26][27][28][29][30][31][32][33][34][35]. Generally, organic electrode materials can be categorized into different types based on their electrochemically active functional groups involved during redox reaction, which includes conjugated carbonyl compounds, conducting polymers, organosulfides and free radicals.…”

Enhanced adsorption of carbonyl molecules on graphene via π-Li-π interaction: a first-principle study

“…Moreover, the immobilization of active carbonyl molecules onto carbon materials especially graphene also offers an effective approach to suppress the dissolution [21][22][23]. Liang et al [24] proved that introducing anthracene-9,10-dione (AQ) and its derivatives onto graphene is effective to prevent the dissolution. However, how the carbonyl molecules interact with graphene and its influence on electrochemical performance are still ambiguous.…”