Mechanism and Mitigation of Irreversible Material Loss within Gel-Based Single-Walled Carbon Nanotube Purification Schemes
Mechanism and Mitigation of Irreversible Material Loss within Gel-Based Single-Walled Carbon Nanotube Purification Schemes
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DOI：
10.1021/acs.jpcc.1c05832
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发表时间：
2021-12-02
影响因子：
3.7
通讯作者：
Tvrdy，Kevin
中科院分区：
文献类型：
--
作者：
Watts，Brennan P.;Rolsma，Caleb;Tvrdy，Kevin
基于葡聚糖凝胶的单壁碳纳米管 (SWCNT) 分离可以根据类型（金属/半导体）和能带结构（手性）对样品进行富集。然而，基于Sephacryl 的方法存在处理效率低的问题，因为一些纯化的单壁碳纳米管仍然不可逆地结合在凝胶上。这项工作的重点是阐明与 Sephacryl S200 不可逆保留 SWCNT 相关的机制，并确定减少材料损失的策略。通过探测吸附过程中的单壁碳纳米管或十二烷基硫酸钠 (SDS) 浓度、负载比（单壁碳纳米管数量与凝胶结合位点数量）以及亲液添加剂对过程洗脱效率的影响等系统参数，本工作确定了单壁碳纳米管的不均匀特征是促进其不可逆保留的主要因素。研究发现，工艺洗脱效率与增加的 SDS 表面活性剂浓度和增加的 SWNT 负载量呈负相关，并且确定了减少基于 Sephacryl 的 SWCNT 分离方案中材料损失的方法。研究发现，与单独使用 SDS 表面活性剂相比，使用强亲液剂 NaF 从 Sephacryl 中洗脱 SWCNT 可将过程洗脱效率从 54% 提高到 88%。总的来说，这项工作既改进了Sephacryl 纯化SWNT 的方法，又提供了宝贵的见解。
Sephacryl-based separation of single-walled carbon nanotubes (SWCNTs) has afforded the enrichment of samples according to both type (metal/semiconducting) and band structure (chirality). However, Sephacryl-based procedures suffer from low process efficiency, in that some of the purified SWCNTs remain irreversibly bound on the gel. This work focuses on the elucidation of mechanistic aspects relating to the irreversible retention of SWCNT by Sephacryl S200 and identification of strategies to reduce material loss. By probing system parameters such as SWCNT or sodium dodecyl sulfate (SDS) concentration during adsorption, loading ratio (number of SWCNTsvs.number of gel binding sites), and the effect of kosmotropic additives on process elution efficiency, this work identifies inhomogeneous features belonging to SWCNTs as the primary factor which promotes their irreversible retention. Process elution efficiency is found to be negatively correlated with increased SDS surfactant concentration and increased SWNT loading, and methods are identified to mitigate material losses in Sephacryl-based SWCNT separation schemes. Application of NaF, a strong kosmotropic agent, to elute SWCNTs from Sephacryl is found to increase process elution efficiency from 54% to 88% compared to SDS surfactant alone. Collectively, this work both improves upon and provides valuable insight into the purification of SWNT with Sephacryl.