02524nas a2200301   4500008004100000022001400041245011100055210006900166260000800235300001200243490000700255520151500262653002701777653002801804653001701832653002701849653002701876100002101903700001701924700002201941700001801963700003601981700001402017700002302031700001902054700003002073856011902103       2022                        eng d  a1614-683200aIncorporating conducting polypyrrole into a polyimide COF for carbon-free ultra-high energy supercapacitor0 aIncorporating conducting polypyrrole into a polyimide COF for ca  cSEP  a22007540 v123 a<p>
	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 (approximate to 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 mu Wh cm(-2)) and power densities (4509 mu W 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.</p>
10acarbon free capacitors10acation-anion co-storage10aconductivity10ahigh energy capacitors10apolypyrrole doped COFs1 aHaldar, Sattwick1 aRase, Deepak1 aShekhar, Pragalbh1 aJain, Chitvan1 aVinod, Chathakudath, Prabhakara1 aZhang, En1 aShupletsov, Leonid1 aKaskel, Stefan1 aVaidhyanathan, Ramanathan  uhttp://library.ncl.res.in/content/incorporating-conducting-polypyrrole-polyimide-cof-carbon-free-ultra-high-energy02408nas a2200289   4500008004100000022001400041245011300055210006900168260000800237490000700245520141200252653003201664653002301696653001501719653002301734653002101757100002001778700001801798700002201816700001701838700002701855700001601882700002301898700003601921700003001957856013101987       2023                        eng d  a1614-683200aMade to measure squaramide COF cathode for zinc dual-ion battery with enriched storage via redox electrolyte0 aMade to measure squaramide COF cathode for zinc dualion battery   cSEP0 v133 a<p>
	Aqueous rechargeable batteries are promising grid-scale energy storage devices because of their affordability, operational safety, and environmental benignity. Among these, Zn-ion batteries (ZIBs) have unfolded new horizons. Designing superior cathodes for ZIBs is crucial. Covalent organic frameworks (COFs) can be made redox active with a high storage surface. Here, for the first time, a chelating COF with redox-active ZnI2 in a ZnSO4(aq) electrolyte is combined. Including iodide harvests an approximately threefold enhancement in capacity from 208 to 690 mAh g(-1) at 1.5 A g(-1), the highest among all the COF-derived ZIBs. Remarkably, a charge-discharge curve at 1.3 V exhibits very limited dropout voltage and super-flat platform, with a remarkable capacity of 600 mAh g(-1) at 5 A g(-1) stable up to 6000 cycles, confirming that the polyiodide generation and storage are sustainable. The COF's dual-ion storage (Zn2+ and polyidode) delivers a ZIB with the highest energy density. Spectro-electrochemical measurements coupled with X-ray photoelectron spectroscopy unambiguously unveil the existence of multiple polyiodide species, with I-3(-) and IO3- ions as the prominent species. The latter gets reduced at the COF electrode under an applied potential, leaving I-3(-) as the major species stored on the COF. The prospect of COF-polyiodide((aq)) is a windfall for metal-ion batteries.</p>
10acovalent organic frameworks10aflexible batteries10apolyiodide10aredox electrolytes10aZn ion batteries1 aKushwaha, Rinku1 aJain, Chitvan1 aShekhar, Pragalbh1 aRase, Deepak1 aIllathvalappil, Rajith1 aMekan, Deep1 aCamellus, Augastus1 aVinod, Chathakudath, Prabhakara1 aVaidhyanathan, Ramanathan  uhttp://library.ncl.res.in/content/made-measure-squaramide-cof-cathode-zinc-dual-ion-battery-enriched-storage-redox-electrolyte