Redox‐active covalent organic frameworks (COFs) store charges but possess inadequate electronic conductivity. Their capacitive action works by storing H+ ions in an acidic electrolyte and is typically confined to a small voltage window (0–1 V). Increasing this window means higher energy and power density, but this risks COF stability. Advantageously, COF's large pores allow the storage of polarizable bulky ions under a wider voltage thus reaching higher energy density. Here, a COF–electrode–electrolyte system operating at a high voltage regime without any conducting carbon or redox active oxides is presented. Conducting polypyrrole (Ppy) chains are synthesized within a polyimide COF to gain electronic conductivity (≈10 000‐fold). A carbon‐free quasi‐solid‐state capacitor assembled using this composite showcases high pseudo‐capacitance (358 mF cm−2@1 mA cm−2) in an aqueous gel electrolyte. The synergy among the redox‐active polyimide COF, polypyrrole and organic electrolytes allows a wide‐voltage window (0–2.5 V) leading to high energy (145 μWh cm−2) and power densities (4509 μW cm−2). Amalgamating the polyimide‐COF and the polypyrrole as one material minimizes the charge and mass transport resistances. Computation and experiments reveal that even a partial translation of the modules/monomers intrinsic electronics to the COF imparts excellent electrochemical activity. The findings unveil COF‐confined polymers as carbon‐free energy storage materials.

Covalento rganic frameworks are an ew class of crystalline organic polymers possessing ah igh surfacea rea and ordered pores. Judicious selection of buildingb locks leads to strategic heteroatom inclusion into the COF structure. Owing to their high surfacea rea, exceptional stability and molecular tunability,C OFs are adopted for various potential applications. The heteroatoms lining in the pores of COF favor synergistich ost-guest interaction to enhance a targeted property.I nt his report, we have synthesized ar esorcinol-phenylenediamine-based COF which selectively adsorbs CO 2 into its micropores (12 ). The heat of adsorption value (32 kJ mol À1 )o btainedf rom the virial model at zero-loading of CO 2 indicates its favorable interaction with the framework. Furthermore, we have anchored small-sized Ag nanoparticles ( % 4-5 nm) on the COF and used the composite for chemicalf ixationo fC O 2 to alkylidenec yclic carbonates by reacting with propargyl alcohols under ambient conditions. Ag@COFc atalyzes the reaction selectively with an excellent yield of 90 %. Recyclability of the catalyst has been demonstrated up to five consecutivec ycles. The postcatalysis characterizations revealt he integrity of the catalyst even after fiver eaction cycles.T his study emphasizes the ability of COF for simultaneous adsorption and chemical fixation of CO 2 into corresponding cyclic carbonates.

Capacitors are the most practical high‐storage and rapid charge‐release devices. The number of ions stored per unit area and their interaction strength with the electrode dictates capacitor‐performance. Microporous materials provide a high storage surface and optimal interactions. Adsorbing electron‐rich and easily polarizable molecules into microporous electrodes is expected to boost Faradaic pseudo‐activity. If such electrode–electrolyte interactions can be made as a potential‐driven reversible process, the resulting capacitors would be adaptable and device‐friendly. A composite covalent organic framework (COF)‐carbon electrode with redox‐active KI is combined in an H2SO4 electrolyte for the first time. This composite electrode benefits from the redox‐functionality of COF and electronic conductivity of carbon, leading to superior capacitative activity. Operando spectro‐electrochemical measurements reveal the existence of multiple polyiodide species, although the I3− is the predominantly electroactive species adsorbing on the microporous triazine‐phenol COF electrode. A systematic fabrication of the flexible solid‐state devices using the COF‐redox‐electrolyte reveals a high areal capacitance of 270 ± 11 mF cm−2 and gravimetric capacitance of 57 ± 8 F g−1. The inclusion of KI in H2SO4 (electrolyte) yields an approximately eight‐fold enhancement in solid‐state gravimetric specific capacitance. The imine‐COF retains 89% of its capacity even after 10 000 cycles.

Adaptable polymer-based solid-state electrolytes can be a game-changer to safe, lightweight flexible batteries. We present a robust Bakelite-type organic polymer covalently decked with viologen, triazine, and phenolic moieties. Its flexible...

Developing stable active catalysts for reducing water-soluble pollutants is a desirable target. In this pursuit, we have functionalized covalent organic frameworks (COFs) with gold (Au) and cobalt (Co) nanoparticles via a one-step aqueous synthesis process, and their catalytic activity in reducing methyl orange and methylene blue is examined. Operando absorbance measurements of methyl orange (anionic dye) reduction revealed AuCoCOF (1.3 Au/1.0 Co) to have superior kinetics over many other catalysts, which typically require additional external stimuli (e.g., photons) and higher catalyst loadings. After confirming the homogeneous dispersion of the nanoparticles on the COF support using three-dimensional (3D) tomography and material stability through powder X-ray diffraction (PXRD), infrared (IR), and thermal studies, we investigated their redox activity. Cyclic voltammetry (CV) confirmed the involvement of both metals in the redox process, while spectroelectrochemical measurements show that their activity and kinetics remain unaltered by an applied potential. Solid-state UV measurements reveal that the neat COF is a semiconductor with a large band gap (2.8 eV), which is substantially lowered when loaded with cobalt nanoparticles (2.2 eV for CoCOF). The electronic synergy between Au and Co nanoparticles further reduces the band gap of AuCoCOF (1.9 eV). Thus, there is a definite advantage in doping non-noble metal nanoparticles into a noble metal lattice and nanoconfining them into a porous COF support. Our study highlights the significance of bimetallic COF-supported nanocatalysts, wherein one can engage each component toward targeted applications that demand redox activity with favorable kinetics.