Cation-Dependent Stabilization of Electrogenerated Naphthalene Diimide Dianions in Porous Polymer Thin Films and Their Application to Electrical Energy Storage

Autor(es)

DeBlase, Catherine R. ^[1] ; Hernandez-Burgos, Kenneth ^[1] ; Rotter, Julian M. ^{[2, 3]} ; Fortman, David J. ^[1] ; Abreu, Dieric dos S. ^{[4, 5]} ; Timm, Ronaldo A. ; Diogenes, Izaura C. N. ^{[4, 5]} ; Kubota, Lauro T. ; Abruna, Hector D. ^[1] ; Dichtel, William R. ^[1]

Afiliação do(s) autor(es)

^[1] Cornell Univ, Chem & Chem Biol, Ithaca, NY 14853 - USA

^[2] Univ Munich LMU, Dept Chem, D-81377 Munich - Germany

^[3] Univ Munich LMU, Ctr NanoSci CeNS, D-81377 Munich - Germany

^[4] Univ Fed Ceara, Dept Quim Organ & Inorgan, BR-60455970 Fortaleza, Ceara - Brazil

^[5] Univ Estadual Campinas, Inst Chem, Dept Analyt Chem, BR-13083 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ANGEWANDTE CHEMIE-INTERNATIONAL EDITION; v. 54, n. 45, p. 13225-13229, NOV 2 2015.
• Citações Web of Science: 36

Resumo

Porous polymer networks (PPNs) are attractive materials for capacitive energy storage because they offer high surface areas for increased double-layer capacitance, open structures for rapid ion transport, and redox-active moieties that enable faradaic (pseudocapacitive) energy storage. Here we demonstrate a new attractive feature of PPNsthe ability of their reduced forms (radical anions and dianions) to interact with small radii cations through synergistic interactions arising from densely packed redox-active groups, only when prepared as thin films. When naphthalene diimides (NDIs) are incorporated into PPN films, the carbonyl groups of adjacent, electrochemically generated, NDI radical anions and dianions bind strongly to K+, Li+, and Mg2+, shifting the formal potentials of NDI's second reduction by 120 and 460mV for K+ and Li+-based electrolytes, respectively. In the case of Mg2+, NDI's two redox waves coalesce into a single two-electron process with shifts of 240 and 710mV, for the first and second reductions, respectively, increasing the energy density by over 20% without changing the polymer backbone. In contrast, the formal reduction potentials of NDI derivatives in solution are identical for each electrolyte, and this effect has not been reported for NDI previously. This study illustrates the profound influence of the solid-state structure of a polymer on its electrochemical response, which does not simply reflect the solution-phase redox behavior of its monomers. (AU)

• Processo FAPESP: 13/25527-1 - Investigação de adsorção em grafeno e óxido de grafeno por espectroeletroquímica Raman
• Beneficiário: Ronaldo Adriano Timm
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Pós-Doutorado