Lithium n‐Doped Polyaniline as a High‐Performance Electroactive Material for Rechargeable Batteries

Abstract

The discovery of conducting lithium‐doped polyaniline with reversible redox chemistry allows simultaneous unprecedented capacity and stability in a non‐aqueous Li battery. This compound (lithium emeraldinate) was synthesized by lithium–proton exchange on the emeraldine base in an anhydrous lithium‐based electrolyte. A combination of UV/Vis‐NIR spectroelectrochemistry, XPS, FTIR, and EQCM characterization allowed a unified description of the chemical and electrochemical behavior, showing facile charge delocalization of the doped states and the reversibility of the redox processes in this form of polyaniline. From a practical point of view, lithium emeraldinate behaves as a high‐capacity organic active material (230 mAh g−1) that enables preparation of relatively thick composite electrodes with a low amount of carbon additives and high energy density (460 Wh kg−1). Concomitantly, at 1C rate, 400 cycles were achieved without significant capacity loss, while the coulombic efficiency is greater than 99 %.

Recent progress in organic electrodes for zinc-ion batteries

“…It has been accepted that among three states (leucoemer-aldine, pernigraniline, emeraldine) of PANI, the emeraldine form of PANI at the half-oxidized state can be doped (protonated) after acid doping and the resulting emeraldine salt possesses high electrical conductivity; while leucoemeraldine (fully reduced state) and pernigraniline (fully oxidized state) are insulators even when doped with acid (Fig. 7) [61,62] . When charging, PANI can lose electrons, together with the acceptance of anions from the electrolytes; while reactions are reversed in the discharge process.…”

A Porphyrin Complex as a Self‐Conditioned Electrode Material for High‐Performance Energy Storage

“…Figure 2c shows af lat voltage plateau at about 4.1 Vf or the initial charging,which is consistent with the above-described irreversible feature in the CV.After the first charging process, ah ighly reversible discharge/charge event is indicated. No welldefined voltage plateau is present in the charge/discharge profiles,t hus indicating rapid multiple redox reactions without clear phase transitions.Asimilar sloping curve has often been observed in organic electrodes with pseudocapacitive behavior, [16,[34][35][36] and most likely arises from the successive movement of electrons into the unoccupied molecular orbitals.Furthermore,the dQ/dV plots reveal subtle potential peaks implying multiple-electron transfer during discharge (Figure 2d). No welldefined voltage plateau is present in the charge/discharge profiles,t hus indicating rapid multiple redox reactions without clear phase transitions.Asimilar sloping curve has often been observed in organic electrodes with pseudocapacitive behavior, [16,[34][35][36] and most likely arises from the successive movement of electrons into the unoccupied molecular orbitals.Furthermore,the dQ/dV plots reveal subtle potential peaks implying multiple-electron transfer during discharge (Figure 2d).…”

“…According to the mass of CuDEPP (50 wt %o ft he total electrode), the discharge capacity of 182 mAh g À1 in the 3rd cycle is close to the theoretical value of 187 mAh g À1 correlated to the four-electron reaction [CuDEPP] 2+ $ [CuDEPP] 2À .T he capacity contribution of carbon black of 5mAh g À1 is neglected herein (see Figure S15). No welldefined voltage plateau is present in the charge/discharge profiles,t hus indicating rapid multiple redox reactions without clear phase transitions.Asimilar sloping curve has often been observed in organic electrodes with pseudocapacitive behavior, [16,[34][35][36] and most likely arises from the successive movement of electrons into the unoccupied molecular orbitals.Furthermore,the dQ/dV plots reveal subtle potential peaks implying multiple-electron transfer during discharge (Figure 2d).…”

Template‐Oriented Polyaniline‐Supported Palladium Nanoclusters for Reductive Homocoupling of Furfural Derivatives

“…[5] Taking advantage of these properties, PANI-based materials have been used in various fields, such as electrode materials and heterogeneous catalysts. [6] Importantly, the π-conjugated structures and the abundant N atoms in PANI can interact with the d orbitals of metals. [7] However, it is difficult to control the morphology and half-oxidized state of PANIfunctionalized Pd catalysts with strong oxidizing agents (such as ammonium persulfate) used in conventional preparation methods.…”