A Symmetric All‐Organic Proton Battery in Mild Electrolyte

Abstract

All‐organic proton batteries are attracting extensive attention due to their sustainability merits and excellent rate capability. Generally, strong acids (e.g. H2SO4) have to be employed as the electrolytes to provide H+ for all‐organic proton batteries due to the high H+ intercalation energy barrier. Until now, the design of all‐organic proton batteries in mild electrolytes is still a challenge. Herein, a poly(2,9‐dihydroquinoxalino[2,3‐b]phenazine) (PO) molecule was designed and synthesized, where the adjacent C=N groups show two different chemical environments, resulting in two‐step redox reactions. Moreover, the two reactions possess considerable voltage difference because of the large LUMO energy gap between PO and its reduction product. More impressively, the C=N groups endow the π‐conjugated PO molecule with H+ uptake/removal in the ZnSO4 electrolyte. As a result, a symmetric all‐organic proton battery is achieved in a mild electrolyte for the first time, which exhibits enhanced electrochemical performance and also broadens the chemistry of proton‐based batteries.

Aqueous proton battery stably operates in mild electrolyte and low-temperature conditions

“…4d), which is better than the reported works. 18,[20][21][22][29][30][31] Beneting from the highly reversible deposition/dissolution of Mn 2+ /MnO 2 on the CF electrode and fast uptake/removal of H + in the PANI anode, the APB showed satisfactory electrochemical performance. Two coin batteries in series can drive the LED lights to work properly (Fig.…”

“…Matching suitable electrode materials for the cathode and anode is the key to constructing APBs. To date, various anode materials (e.g., quinone-based organic materials, 20,21 conjugate amine compounds, 22,23 transition metal oxides, 24,25 etc.) have been reported, but few cathode materials can be selected due to the lack of original H + -host materials.…”

Bis-imidazole ring-containing bipolar organic small molecule cathodes for high-voltage and ultrastable lithium-ion batteries

“…As a result, in BNBQ molecules, the O in p -benzoquinone and pyridinic N in imidazole rings with more negative MESP values should be the active sites for Li + uptake (Fig. 3f), 53 and –NH– of the imidazole ring with a positive MESP might be attractive to anions, which would be beneficial for PF 6 − insertion.…”

Electrochemical Proton Storage: From Fundamental Understanding to Materials to Devices

“…Other organic electrode materials with C=N groups or N=N groups can also achieve reversible proton storage. A poly(2,9-dihydroquinoxalino[2,3- b ] phenazine) (PO) organic material was synthesized to design an all-organic proton battery that delivered a specific capacity of 147 mAh g −1 with a long-term cycle life of over 500 cycles in mild electrolyte [ 96 ]. The chemical environments of adjacent C=N groups in PO molecules are different enough to result in a two-step redox reaction (Fig.…”

“…Copyright 2017, The Royal Society of Chemsitry. b Ex situ FTIR spectra of PO electrodes during charging and discharging process [ 96 ]. Copyright 2021, Wiley–VCH.…”