Charge/Discharge Properties of Organometallic Batteries Fabricated with Ferrocene–Containing Polymers

Abstract

A group of ferrocene‐containing polymers were synthesized from vinylferrocene, ethynylferrocene and 1,1′‐dibromoferrocene, and properties of the formed polymers were examined to clarify their potential as a new class of cathode‐active, charge‐storage materials for rechargeable batteries. Vinylferrocene polymerized with 2,2′‐azoisobutyronitrile (AIBN) to give a polymer with number‐average molecular weights of 2 200–5 100 g · mol−1 in 12–41% yields, while ethynylferrocene and 1,1′‐dibromoferrocene polymerized with Rh catalysts and by step‐growth mechanism, respectively, to provide insoluble polymers in 71–96% yields. The capacities of organometallic rechargeable cells fabricated with poly(vinylferrocene), poly(ethynylferrocene), and poly(ferrocene) reached 105, 105, and 95 Ah · kg−1, respectively. In particular, poly(vinylferrocene) displayed completely reversible charge/discharge processes featuring a constant voltage of around 3.5 V.magnified image

Synthesis and Charge–Discharge Properties of Organometallic Co­polymers of Ferrocene and Triphen­ylamine as Cathode Active Materials for Organic‐Battery Applications

“…[39] For example, in the IR spectrum of PVFVM1, the peak at ν = 3058 cm -1 is typical of the C-H stretching of ferrocene, whereas the peaks at ν = 1591 and 1490 cm -1 are due to the C=C stretching signals of the triphenylamine moieties, the peak at ν = 1276 cm -1 is due to C-N stretching, the peaks at ν = 1107 and 1000 cm -1 are due to the C-C stretching of ferrocene, and the signals at ν = 824 and 509 cm -1 are due to C-H bending and C-Fe stretching in ferrocene, respectively ( Figures S5 and S6). …”

“…[38] Thus, ferrocene-containing structures have attracted a great deal of attention in the investigation of electrochemical behaviors. [38][39][40][41][42][43] However, some of the reported ferrocene-containing polymeric systems suffer from limitations, such as unstable discharging voltages arising from their conjugated structures with one redox center and capacity fading owing to their low molecular weights, which can result in serious dissolution loss. [39,43a] Compared with the corresponding conjugated polymers bearing active nitroxide radicals in their main skeletons, nonconjugated architectures with pendant nitroxide side chains exhibit more stable electrochemical characteristics after quantitative redox reactions.…”

High-capacity organic positive-electrode material based on a benzoquinone derivative for use in rechargeable lithium batteries

“…However, their cycle-life performance is inadequate because of the dissolution of the active materials into the electrolytes [4,5]. Pendant-type polymers based on a tetramethylpiperidine-N-oxyl (TEMPO) [6] or ferrocene [7] skeleton have been studied as a third type of active material, and these have practical capacities of about 100 mAh g −1 . Recently, low-molecular-weight lithiated oxocarbon salts, which show high capacities up to about 500 mAh g −1 and fair cycle stabilities, have been reported; however, these materials still show limited variation [8,9].…”

Ferrocene-functionalized polyheteroacenes for the use as cathode active material in rechargeable batteries

“…P1 and P2 t thus well to other ferrocene-substituted polymers, such as poly(vinyl ferrocene) 11 with an initial capacity of 83% of the theoretical capacity and a capacity retention of 95% aer 300 cycles, or poly(uorenylethynylene ferrocene)…”