Australian Institute for Bioengineering and Nanotechnology and ‡School of Chemical Engineering, University of Queensland , Brisbane, Queensland 4072, Australia.
ACS Appl Mater Interfaces. 2017 Oct 11;9(40):34900-34908. doi: 10.1021/acsami.7b09604. Epub 2017 Sep 28.
Nitroxide radical polymers can undergo both excellent electrochemical redox reactions and a rapid "click" coupling reaction with carbon-centered radicals (i.e., nitroxide radical coupling (NRC) reaction). In this work, we report a strategy to functionalize poly(2,2,6,6,-tetramethylpiperidinyl-1-oxyl methacrylate) (PTMA) with pyrene side groups through a rapid and near quantitative NRC reaction. This resulted in P(TMA-co-PyMA) random copolymers with near quantitative amounts of pyrene along the PTMA chain for greater π-π interaction with rGO, while the nitroxide radicals on the polymer could simultaneously be used for energy storage. These copolymers can bind with reduced graphene oxide (rGO) and form layered composites through noncovalent π-π stacking, attaining molecular-level dispersion. Electrochemical performance of the composites with different polymer contents (24, 35, and 45 wt %), tested in lithium ion batteries, indicated that the layered structures consisting of P(TMA-co-PyMA) maintained greater capacities at high C-rates. This simple and efficient strategy to synthesize pyrene-functionalized polymers will provide new opportunities to fabricate many other polymer composite electrodes for desired electrochemical performance.
氮氧自由基聚合物可以同时进行出色的电化学氧化还原反应，以及与碳中心自由基的快速“点击”偶联反应（即氮氧自由基偶联（NRC）反应）。在这项工作中，我们报告了一种通过快速且近乎定量的 NRC 反应，在聚（2,2,6,6-四甲基哌啶-1-氧代甲基丙烯酸酯）（PTMA）上用芘侧基官能化的策略。这导致 P(TMA-co-PyMA) 无规共聚物中沿 PTMA 链具有近乎定量的芘，以便与 rGO 进行更大的 π-π 相互作用，而聚合物上的氮氧自由基可以同时用于储能。这些共聚物可以通过非共价 π-π 堆积与还原氧化石墨烯（rGO）结合并形成层状复合材料，实现分子水平的分散。在锂离子电池中测试具有不同聚合物含量（24、35 和 45wt%）的复合材料的电化学性能表明，由 P(TMA-co-PyMA) 组成的层状结构在高 C 率下保持更大的容量。这种合成芘功能化聚合物的简单而有效的策略将为制造许多其他具有所需电化学性能的聚合物复合电极提供新的机会。
