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The nickel salen-type redox polymers represent an interesting class of organometallic polymers frequently used in hybrid supercapacitor electrodes as thin films and carbon material composites. However, the suitability of these compounds for application as electrode materials for rechargeable batteries has not yet been tested. In this study, redox processes in monocomponent electrodes based on a series of nickel salen-type redox polymers are investigated in 1 m LiPF6 in 1:1 ethylene carbonate (EC)/diethyl carbonate (DEC) electrolyte in a Li-ion battery. The oxidation potentials for polymer complexes of nickel exceed 3.5 V versus Li/Li+, which enhances specific energy. It is found that introduction of a proper substituent in the phenyl ring of the ligand allows to fabricate additive-free electrodes which demonstrate high charge/discharge rate performance with the capacity on discharge at 10 C being up to 73% of the capacity obtained at discharge at 1 C, which corresponds to maximum power of 2.6 kW kg−1. [ABSTRACT FROM AUTHOR]

The polycycloaddition of azomethine ylides to dipolarophiles is described for the first time. Use of ( cis, cis)-bis-aziridines as a source of azomethine ylides allows selective polyaddition to be realized, which leads to oligomers exclusively with trans-substituted pyrrolidine rings and modest molecular weights (ca. 5-10 kDa). The fluorescent, electrochemical, electrochromic, and non-linear optical properties of the main-chain free-base porphyrin oligomer, synthesized by the developed procedure, are studied. An enhancement of the optical power limiting effect in a porphyrin oligomer solution is registered against that of the monomer. [ABSTRACT FROM AUTHOR]

Back Cover: Modern gadgets consume tons of Li‐ion batteries, which are mostly based on hazardous inorganic materials. Nickel‐salen‐type organometallic polymers are prospective cathode materials, which alleviate the impact on the environment yet are powerful enough to supply energy for most portable devices. More information can be found in article number 1700361 by Svetlana N. Eliseeva, Elena V. Alekseeva, Anatoliy A. Vereshchagin, Alexey I. Volkov, Petr S. Vlasov, Alexander S. Konev, and Oleg V. Levin*. [ABSTRACT FROM AUTHOR]

Abstract Redox polymers bearing stable nitroxyl radical groups, such as poly-TEMPO-methacrylate (PTMA), are attractive candidates for application in power sources of novel kind, which combine the high power output of supercapacitors and high energy of rechargeable batteries. An important advantage of PTMA is the availability and low cost of the starting materials combined with high charging/discharging voltage, fast electron transfer kinetics and good mechanical properties of the polymer. However, low electron conductivity and high solubility in common organic electrolytes hamper the broad application of TEMPO-based compounds as cathode materials. In the present work, we report a simple strategy to overcome these limitations by the use of a practical and polymer-rich electrode based on redox-conducting polymer blends of polymerized nickel complexes with salen-type Schiff bases and PTMA. Electrochemical properties of the material are tested both in thin film systems and in asymmetric supercapacitor prototypes with aqueous electrolyte, which demonstrate high specific capacity (83 mAh g−1 at 1C, 53 mAh g−1 at 5C and 47 mAh g−1 at 10C), high rate capability as well as cycling stability (55% capacity retention after 1000 cycles). Graphical abstract Image 1 Highlights • Novel TEMPO- and Ni-salen polymer composite cathode material is reported. • Synergistic interaction of the components secures good durability and capacity. • TEMPO-based redox polymer increases the specific capacity and stability in water. • Ni-salen allows to overcome the low conductivity typical for redox polymers. [ABSTRACT FROM AUTHOR]