@article {48735,
	title = {Made to measure squaramide COF cathode for zinc dual-ion battery with enriched storage via redox electrolyte},
	journal = {Advanced Energy Materials},
	volume = {13},
	year = {2023},
	month = {SEP},
	type = {Article},
	abstract = {<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{\textquoteright}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>
},
	keywords = {covalent organic frameworks, flexible batteries, polyiodide, redox electrolytes, Zn ion batteries},
	issn = {1614-6832},
	doi = {10.1002/aenm.202301049},
	author = {Kushwaha, Rinku and Jain, Chitvan and Shekhar, Pragalbh and Rase, Deepak and Illathvalappil, Rajith and Mekan, Deep and Camellus, Augastus and Vinod, Chathakudath Prabhakaran and Vaidhyanathan, Ramanathan}
}
@article {48953,
	title = {Tailoring COFs: transforming nonconducting 2D layered COF into a conducting quasi-3D architecture via interlayer knitting with polypyrrole},
	journal = {Journal of the American Chemical Society},
	volume = {146},
	year = {2023},
	month = {DEC},
	pages = {487-499},
	type = {Journal Article},
	abstract = {<p>Improving the electronic conductivity and the structural robustness of covalent organic frameworks (COFs) is paramount. Here, we covalently cross-link a 2D COF with polypyrrole (Ppy) chains to form a quasi-3D COF. The 3D COF shows well-defined reflections in the SAED patterns distinctly indexed to its modeled crystal structure. This knitting of 2D COF layers with conjugated polypyrrole units improves electronic conductivity from 10(-9) to 10(-2 )S m(-1). This conductivity boost is affirmed by the presence of density of states near the Fermi level in the 3D COF, and this elevates the COF{\textquoteright}s valence band maximum by 0.52 eV with respect to the parent 2D pyrrole-functionalized COF, which agrees well with the opto-electro band gaps. The extent of HOMO elevation suggests the predominant existence of a polaron state (radical cation), giving rise to a strong EPR signal, most likely sourced from the cross-linking polypyrrole chains. A supercapacitor devised with COF20-Ppy records a high areal capacitance of 377.6 mF cm(-2), higher than that of the COF loaded with noncovalently linked polypyrrole chains. Thus, the polypyrrole acts as a {\textquoteleft}{\textquoteleft}conjugation bridge{\textquoteright}{\textquoteright} across the layers, lowering the band gap and providing polarons and additional conduction pathways. This marks a far-reaching approach to converting many 2D COFs into highly ordered and conducting 3D ones.</p>
},
	keywords = {covalent organic frameworks, Electrical conductivity},
	issn = {0002-7863},
	doi = {10.1021/jacs.3c09937},
	author = {Jain, Chitvan and Kushwaha, Rinku and Rase, Deepak and Shekhar, Pragalbh and Shelke, Ankita and Sonwani, Disha and Ajithkumar, Thalasseril G. and Vinod, Chathakudath Prabhakaran and Vaidhyanathan, Ramanathan}
}
