Porous organic polymers are efficient photocatalysts in organic synthesis, hydrogen evolution, CO2 reduction, and degradation of organic pollutants.

Transformation of CO2 into valuable chemicals and especially fuels is deemed as a promising approach to reduce our dependence on fossil fuels and to alleviate climate change. Carbazole-based porous polymers bearing rhenium-metalated polypyridine functionalities were constructed via simple oxidative coupling reaction. These porous polymers are employed as heterogeneous supports for immobilization of catalytically active rhenium complexes and furthermore provide high CO2 adsorption capabilities and light absorption abilities, i.e., photosensitizing properties. Consequently, such rhenium-metalated microporous polycarbazole networks show high efficiencies for CO2 photoreduction upon visible-light irradiation, with a CO evolution rate up to 623 μmol g–1 h–1 and selectivity of 97.8%. The microporous solid photocatalyst shows enhanced stability and photocatalytic performance compared to the molecular catalysts during long-term use.

Photoredox catalysis has aroused great interest from chemists, as it offers a powerful tool for organic synthesis. Cationic polycarbazole networks (CPOP-28 and CPOP-29) were prepared via simple oxidative coupling reaction and applied as heterogeneous photocatalysts for a wide range of oxidative organic transformations, including oxidation of sulfides, hydroxylation of arylboronic acids, and crossdehydrogenative coupling reactions, in the presence of visible light and air. Remarkably, photocatalytic activities are enhanced by ingenious introduction of trifluoromethyl groups to the polymeric network CPOP-29. The effects of the trifluoromethyl group on photocatalytic activities were elucidated in terms of photophysical and electrochemical properties. The appealing photocatalytic performance of the trifluoromethylated polymer is ascribed to superior light-absorption ability, longer fluorescence lifetime, and stronger oxidative capability. In addition, the photocatalysts showed good recyclability and could be reused after a simple separation workup.

NASICON‐type Li1+xAlxTi2−x(PO4)3 (LATP) solid electrolytes have developed as a promising candidate for solid‐state lithium batteries. However, the brittle and stiff LATP suffers from poor physical contact with electrodes and chemical/electrochemical instability at electrode|electrolyte interfaces. Herein, a thin and flexible hybrid electrolyte comprised of LATP and poly(vinylidene fluoride‐trifluorethylene) (PVDF‐TrFE) incorporated with highly concentrated ionic liquid electrolyte (ILE) is prepared to resolve these prominent limitations. To further protect the LATP|Li interface, an ultrathin poly[2,3‐bis(2,2,6,6‐tetramethylpiperidine‐N‐oxycarbonyl)‐norbornene] (PTNB) polymer is coated on Li, acting as an additional protective layer. Consequently, the lithium stripping‐plating lifetime is prolonged from 128 to 792 h, with no dendritic lithium observed. The PTNB@Li||LiNi0.8Co0.1Mn0.1O2 (PTNB@Li||NCM811) cells achieve significantly improved rate capability and cycling stability, predominantly resulting from the drastically decreased interfacial resistances, prohibited dendritic lithium generation, mitigated cathode material phase evolution, and prevention of internal microcrack formation. The thinner interphases formed on NCM811 and PTNB@Li electrodes also play a key role. The quasi‐solid‐state batteries allow for the fabrication of multi‐layer bipolar cells with stable cycling. Even under some exertive circumstances, (limited lithium source, low temperature, e.g., 0 °C), the impressive electrochemical performance achieved highlights the importance of such quasi‐solid‐state lithium batteries as a viable solution for the next‐generation high‐performance lithium batteries.

devices and electric vehicles. [1][2][3][4] To achieve even higher energy densities, the use of lithium metal as the negative electrode is considered the next big step. However, the continuous electrolyte decomposition at the electrode|electrolyte interface, owing to the lack of a stable solid electrolyte interphase (SEI), results in low Coulombic efficiency (CE) and, potentially, dendritic lithium deposition. Thus eventually cause rapid cell failure and, in a worst case, accidental short-circuiting, posing severe safety issues and hindering commercialization. [5][6][7] Nonetheless, there has been a revitalized interest in lithiummetal anodes, encouraged by recent advances towards the stabilization of the anode|electrolyte interface. These advances were achieved by different strategies, including the formulation of beneficial electrolyte compositions, [8] the application of artificial interphases, [9] the use of 3D host matrices, [10] and the replacement of conventional liquid electrolytes by solidstate electrolytes. [11] Among these strategies, the utilization of solid-state electrolytes -inorganic and/or polymeric -potentially provides great advantages concerning the safe operation of lithium-metal anodes. [12,13] The first report on polymer electrolytes, characterized by high flexibility and light weight, dated back to the late 1970s with poly(ethylene oxide) (PEO) serving as the lithium salt dissolving medium. [14,15] Later, gel-type polymer electrolytes were developed by swelling a polymer matrix, such as poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP), polyacrylonitrile (PAN), or poly(vinyl alcohol) (PVA) with a lithium salt-containing liquid electrolyte. [16] In such systems, the polymer essentially takes over the role of the separator and is not actively involved in the charge transport. Differently, the lithium salt anions substantially contribute to the charge transport, resulting in a lithium transference number (t Li + ) well below 0.5. This leads to a large concentration gradient and reversed electric field in the cell, which in turn results in large overpotentials, limited dis-/charge rates, and fast dendrite growth. [17][18][19][20] Accordingly, increasing the t Li + , ideally to a value close to unity, provides a solution to overcome the above mentioned challenges. The most straightforward approach to realize this is the covalent tethering of the anionic function to the polymer to immobilize the negative charge, yielding single-ion Single-ion conducting polymer electrolytes are considered particularly attractive for realizing high-performance solid-state lithium-metal batteries. Herein, a polysiloxane-based single-ion conductor (PSiO) is investigated. The synthesis is performed via a simple thiol-ene reaction, yielding flexible and self-standing polymer electrolyte membranes (PSiOM) when blended with poly(vinylidene fluoride-co-hexafluoropropylene) (PVdF-HFP). When incorporating 57 wt% of organic carbonates, these polymer membranes provide a Li + conductivity of >0.4 mS cm −1 at 20 °C ...

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High-energy Ni-rich lithium transition metal oxides such as Li[Ni 0.8 Co 0.1 Mn 0.1 ]O 2 (NCM 811 ) are appealing positive electrode materials for next-generation lithium batteries. However, the high sensitivity toward moist air during storage and the high reactivity with common organic electrolytes, especially at elevated temperatures, are hindering their commercial use. Herein, an effective strategy is reported to overcome these issues by coating the NCM 811 particles with a lithium phosphonate functionalized poly(aryl ether sulfone). The application of this coating allows for a substantial reduction of lithiumbased surface impurities (e.g., LiOH, Li 2 CO 3 ) and, generally, the suppression of detrimental side reactions upon both storage and cycling. As a result, the coated NCM 811 -based cathodes reveal superior Coulombic efficiency and cycling stability at ambient and, particularly, at elevated temperatures up to 60 °C (a temperature at which the non-coated NCM 811 electrodes rapidly fail) owing to the formation of a stable cathode electrolyte interphase with enhanced Li + transport kinetics and the well-retained layered crystal structure. These results render the herein presented coating strategy generally applicable for high-performance lithium battery cathodes.