Title: Aligned regenerated cellulose-based nanofluidic fibers with ultrahigh ionic conductivity and underwater stability for osmotic energy harvesting

Authors: BinglinZhou, JieZou, ZewanLin, ZhanhongYuan, Xingzhen Qin*, Pan Chen, Dongdong Ye*

Abstract: The growing interest in biomass-based nanofluids has revealed flaws in large-scale manufacturing, customizable aligned nanostructures, and the weak interaction of structural components, resulting in low ionic conductivity, unsatisfactory long-term reliability underwater, and insufficient energy conversion efficiency. Herein, we present a bottom-up strategy integrating cellulose dissolution, orientation, regeneration, and densification to construct regenerated cellulose-based nanofluidic fibers (RCNFs) comprising a high weight content of acidified carbon nanotubes (40%), aligned nanochannels (3–4 nm), and negatively charged surfaces (–3.05 mC m⁻²). Benefited from the synergistic alignment and spatial confinement of CNTs by the cross-linked cellulose network, the RCNFs realized a high underwater strength (29 MPa), unprecedentedly high ionic conductivity (0.07 S cm⁻¹) at low salt concentrations (<0.001 M), and high long-term output power density (2.57 W m⁻² over 43 days) in an artificial river water–seawater system. In a proof-of-concept experiment, customizable RCNF-based devices connected in series powered a calculator and LED lights at a 50-fold concentration gradient. This work can promote the application of regenerated cellulose in high-performance osmotic energy conversion systems

https://doi.org/10.1016/j.cej.2022.141167

生物质纳米流体缺乏大规模制造、可定制取向纳米结构以及较弱的结构组分相互作用，导致离子电导率低、水下长期可靠性不佳以及能量转换效率不足。 本工作，我们首次提出了一种整合纤维素溶解、定向、再生和致密化自下而上的策略用于构建具有高碳纳米管载量(40%)、致密化取向纳米通道 (3–4 nm)，以及高电荷密度 (–3.05 mC m⁻²)的再生纤维素基纳米流体纤维 (RCNF)。 得益于物理化学交联纤维素网络对 CNT 的协同取向和空间限制作用，RCNF 在低盐浓度（<0.001 M）下实现了高水下强度（29 MPa）、前所未有的高离子电导率（0.07 S cm⁻¹） ，以及人工河水-海水系统中的高长期输出功率密度（2.57 W m⁻² 超 43 天）。 在概念验证实验中，串联连接的RCNF基可定制设备在50 倍浓度梯度下可驱动计算器和 LED 灯工作。我们的工作可促进再生纤维素在高性能渗透能转化系统中的应用。

本工作是我课题组在序构化再生纤维素应用领域的最新研究成果，欢迎大家阅读、指导和引用。