Hybrid based on Phenazine Conjugated Microporous Polymer as a High‐Performance Organic Electrode in Aqueous Electrolytes

Abstract

Incorporating redox active units in a 3D porous network is an encouraging strategy to enhance electrochemical performance of organic electrode materials. Herein, a new hybrid composed by phenazine-based conjugated microporous polymer (IEP-27-SR, stand for IMDEA Energy Polymer number 27) and singlewalled carbon nanotubes (SWCNTs) and graphene oxide (RGO) is synthesized, fully characterized and tested electrochemically in different aqueous electrolyte conditions, i. e., at various pH values (1-12) and also with different charge carriers (H + in acidic, and Li + , Na + , K + in neutral and alkaline electrolytes).Although the IEP-27-SR is found to be very versatile showing very good electrochemistry both in alkaline and acidic solution, it exhibits best specific capacity, redox kinetics and cycle stability in acidic electrolyte. Then encouragingly, when IEP-27-SR is combined with an activated carbon (AC) counter electrode to construct a proof-of-the-concept device, the IEP-27-SR//AC demonstrates high specific capacity (168 mAh g À 1 at 2 C), impressive rate performance (96 mAh g À 1 at 60 C) and ultralong cycle stability (76 % capacity retention over 28800 cycles at 10 C; 2690 h) in 1 M H 2 SO 4 .

A phenazine-based conjugated microporous polymer as a high performing cathode for aluminium–organic batteries

“…1a). 32 The polymerization process, via the Sonogashira cross-coupling reaction, involves 2,7-dibromophenazine ( 1 ) and 1,3,5-triethylbenzene ( 2 ) as building blocks that react in the presence of SWCNTs and rGO. This reaction pathway favours intimate contact between the nanocarbons and the porous polymer within the hybrid material.…”

“…1b). 32 The isotherm has a type IV shape, typical of mesoporous materials. The measured specific surface area ( S BET ) is 765 m 2 g −1 .…”

“…The conjugated microporous hybrid polymer based on phenazine (named IEP-27-SR, where S = SWCNT and R = rGO) was synthesized following a two-step polymerization that combined the miniemulsion and solvothermal methods previously reported by us. 32 SWCNTs (8.10 mg) and rGO (8.10 mg) were dispersed using an ultrasonic tip in toluene (8 mL) for 10 min. Then, 2,7-dibromophenazine ( 1 ) (250 mg, 0.74 mmol, 1.5 eq.)…”

“…Until now, the application of "n-type" phenazine-based materials as electrodes has been limited to non-aqueous Li batteries 31,18 and aqueous rechargeable batteries. [32][33][34][35] However, they have not been investigated in non-aqueous RABs to date. Recently, our group developed and tested a new hybrid CMP based on phenazine (named IEP-27-SR) in both acidic and alkaline aqueous electrolytes, demonstrating excellent robustness and electrochemical performance.…”

Hypercrosslinked Phenothiazine Polymer as a Low-Cost and Durable Organic Cathode for Rechargeable Lithium Batteries

“…An IEP-29 buckypaper electrode was prepared by dispersing together SWCNT/rGO and IEP-29 in NMP and IPA solvents (1:1, v/v), followed by vacuum-assisted filtration processes, as reported in our recent articles. , As an example, the buckypaper of 50 wt % IEP-29 is prepared as follows: 10 mg of IEP-29 was mixed with 7.5 mg of SWCNTs and 2.5 mg of RGO in 14 mL of NMP and IPA mixture. The suspension was stirred overnight at room temperature, and the formed ink was tip-sonicated for an hour.…”