title: Mussel inspired modification of polypropylene separators by catechol/polyamine for Li-ion batteries.
abstract: Inspired by the remarkable adhesion of mussel, dopamine, a mimicking adhesive molecule, has been widely used for surface modification of various materials ranging from organic to inorganic. However, dopamine and its derivatives are expensive which impede their application in large scale. Herein, we replaced dopamine with low-cost catechol and polyamine (only 8% of the cost of dopamine), which could be polymerized in an alkaline solution and deposited on the surfaces of various materials. By using this cheap and simple modification method, polypropylene (PP) separator could be transformed from hydrophobic to hydrophilic, while the pore structure and mechanical property of the separator remained intact. The uptake of electrolyte increased from 80% to 270% after the hydrophilic modification. Electrochemical studies demonstrated that battery with the modified PP separator had a better Coulombic efficiency (80.9% to 85.3%) during the first cycle at a current density of 0.1 C, while the discharging current density increased to 15 C and the discharge capacity increased by 1.4 times compared to the battery using the bare PP separator. Additionally, the modification allowed excellent stability during manifold cycles. This study provides new insights into utilizing low-cost chemicals to mimic the mussel adhesion and has potential practical application in many fields.
authors.affiliation: Beijing National Laboratory for Molecular Sciences, Laboratory of Polymer Physics and Chemistry, Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, People's Republic of China.
authors.forename: Hao
authors.initials: H
authors.lastname: Wang
authors.forename: Junjie
authors.initials: J
authors.lastname: Wu
authors.forename: Chao
authors.initials: C
authors.lastname: Cai
authors.forename: Jing
authors.initials: J
authors.lastname: Guo
authors.forename: Haosen
authors.initials: H
authors.lastname: Fan
authors.forename: Caizhen
authors.initials: C
authors.lastname: Zhu
authors.forename: Haixia
authors.initials: H
authors.lastname: Dong
authors.forename: Ning
authors.initials: N
authors.lastname: Zhao
authors.forename: Jian
authors.initials: J
authors.lastname: Xu
mesh_terms: D000818:Animals; D049872:Bivalvia; D002396:Catechols / Q000737:chemistry*; D011211:Electric Power Supplies; D004573:Electrolytes / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008094:Lithium / Q000737:chemistry*; D011073:Polyamines / Q000737:chemistry*; D011126:Polypropylenes / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D002396:Catechols; D004573:Electrolytes; D011073:Polyamines; D011126:Polypropylenes; D008094:Lithium; C034221:catechol