Functionalized Nanocellulose-Integrated Heterolayered Nanomats toward Smart Battery Separators

• Published in: Nano letters Vol. 16; no. 9; pp. 5533 - 5541
• Main Authors: Kim, Jung-Hwan, Gu, Minsu, Lee, Do Hyun, Kim, Jeong-Hoon, Oh, Yeon-Su, Min, Sa Hoon, Kim, Byeong-Su, Lee, Sang-Young
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 14.09.2016
• Subjects: metal-ion chelation; functionalized nanocellulose; Separator membranes; heterolayered nanomat; molecular simulation
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.6b02069

Alternative materials obtained from natural resources have recently garnered considerable attention as an innovative solution to bring unprecedented advances in various energy storage systems. Here, we present a new class of heterolayered nanomat-based hierarchical/asymmetric porous membrane with synergistically coupled chemical activity as a nanocellulose-mediated green material strategy to develop smart battery separator membranes far beyond their current state-of-the-art counterparts. This membrane consists of a terpyridine (TPY)-functionalized cellulose nanofibril (CNF) nanoporous thin mat as the top layer and an electrospun polyvinylpyrrolidone (PVP)/polyacrylonitrile (PAN) macroporous thick mat as the support layer. The hierarchical/asymmetric porous structure of the heterolayered nanomat is rationally designed with consideration of the trade-off between leakage current and ion transport rate. The TPY (to chelate Mn2+ ions) and PVP (to capture hydrofluoric acid)-mediated chemical functionalities bring a synergistic coupling in suppressing Mn2+-induced adverse effects, eventually enabling a substantial improvement in the high-temperature cycling performance of cells.