文献类型：期刊文献

英文题名：Diameter-selective separation of small-diameter single-walled carbon nanotubes via reversed-phase aqueous two-phase extraction

作者：Cao, Xiaodi[1];Li, Guo[1];Cao, Meixia[2];Yang, Xing[1];Leng, Xinran[1];Hu, Ping[3];Liu, Gang[2];Zhang, Hongyang[3];Zhang, Min[1,4]

机构：[1]East China Univ Sci & Technol, Shanghai Frontiers Sci Ctr Optogenet Tech Cell Met, Shanghai 200237, Peoples R China;[2]Shanghai Inst Measurement & Testing Technol Co Ltd, Key Lab Bioanal & Metrol, State Adm Market Regulat, Shanghai 201203, Peoples R China;[3]East China Univ Sci & Technol, Dept Chem, Shanghai Key Lab Funct Mat Chem, Shanghai 200237, Peoples R China;[4]East China Univ Sci & Technol, Engn Res Ctr Pharmaceut Proc Chem, Minist Educ, Shanghai 200237, Peoples R China

年份：2026

卷号：260

外文期刊名：CARBON

收录：;EI(收录号：20263121205883);Scopus(收录号：2-s2.0-105045940510);WOS:【SCI-EXPANDED(收录号:WOS:001838952200001)】；

基金：The authors acknowledge the National Natural Science Foundation of China (Nos. 81573397 and 81973285) and the Shanghai Frontiers Science Center of Optogenetic Techniques for Cell Metabolism.

语种：英文

外文关键词：Single-walled carbon nanotubes; Aqueous two-phase extraction; Chirality-selective separation; Reversed-phase ATPE; Partition coefficient; Separation mode

摘要：Aqueous two-phase extraction (ATPE) is widely used for chirality-selective separation of single-walled carbon nanotubes (SWCNTs), but conventional SDS-driven normal-phase ATPE (NP-ATPE) often leaves small-diameter species as late-transferring components with broadened transfer windows and limited resolution. To address this limitation, we implement a reversed-phase ATPE (RP-ATPE) operation in which SWCNTs are initially stabilized in the polyethylene glycol (PEG)-rich upper phase and subsequently transferred into the dextran (Dex)-rich lower phase through sodium cholate-induced surfactant exchange-an operational reversal that inverts the initial phase reservoir and transfer direction without changing the physical identities of the two polymer phases. RPATPE reverses the diameter-dependent transfer order, leading to the preferential extraction of small-diameter species and providing narrower transfer windows, higher separation resolution, higher purity for selected small-diameter semiconducting species (e.g., (6,4) and (7,3)), and fewer sequential fractionation steps, whereas NP-ATPE remains more favorable for larger-diameter species. We established an empirical relationship between surfactant concentration and partition coefficient via Hill-type fitting and used this relationship to develop a graphical selection map that guides mode selection and surfactant optimization. Mechanistically, this performance inversion originates from the reversed surfactant-exchange trajectory, which alters the evolution pathway of the partition coefficient and thereby reverses the phase-transfer thresholds of different chiralities. This work establishes the phase-transfer direction as an independent operational design variable in ATPE, providing a predictive framework for rational chirality-selective SWCNT separation.