导电水凝胶是构建柔性传感器和可穿戴电子的重要材料，可在弯曲、拉伸等形变条件下实现信号传导和人体运动监测。为提高其导电性和稳定性，以往的工作通常采用PEDOT:PSS分散液作为导电填料。然而，PSS属于石化基聚合物，带来不可再生和不可降解的问题，同时PEDOT:PSS分散液在冻干或长时间存储后容易聚集沉淀，严重限制了其应用。此外，水凝胶在低温环境下往往会因水分结冰而失去柔韧性和导电性，导致传感性能衰减。如何同时实现 绿色可持续性、高导电性、力学韧性以及极端环境适应性，仍是导电水凝胶面临的关键挑战。

  针对这一问题，近日，中国林业科学研究院林产化学工业研究所储富祥研究员团队提出了一种基于高取代度硫酸化纤维素（Sulfated Cellulose，SC）的绿色稳定策略。研究人员通过均相硫酸化制备了高取代度SC，并以其为稳定剂和反应模板，诱导3,4-乙烯二氧噻吩（EDOT）原位氧化聚合，获得了稳定的PEDOT:SC分散液。该分散液不仅具备优异的胶体稳定性和导电性（1.75 S/cm），还可在冻干后实现完全再分散。在此基础上构建出兼具高强度（伸长率650%、强度390 kPa）、高导电性（52.4 mS/cm）、抗冻（–20 °C 仍具41.7 mS/cm和900%拉伸率）及强粘附性的多功能水凝胶（图1）。该材料不仅能在极端条件下灵敏监测人体运动，还可输出莫尔斯电码实现“SOS”等应急通信，为极端环境可穿戴电子和柔性传感器提供了新型材料平台。

Figure 1. (a) Schematic illustration of the preparation process of SC and PEDOT:SC dispersions. (b) Fabrication process of the PEDOT:SC/PAM hydrogel. (c) Illustration of the motion-sensing performance of the hydrogel at 25?°C and –20?°C.

  图1说明了以高取代度硫酸化纤维素稳定PEDOT分散液，并构建具备强韧性、导电性和抗冻性的多功能水凝胶的设计策略。

Figure 2. (a) Sulfur content, (b) degree of substitution and yield, and (c) FTIR spectra of SC samples prepared at different reaction times.

  图2通过结构分析验证SC的成功制备，以及对其取代度的验证，证明其能够作为PEDOT的绿色稳定剂。

Figure 3. (a) FTIR spectra of PEDOT and PEDOT:SC samples prepared with varying SC contents. (b) Raman spectra of PEDOT:SC with different SC contents. (c) XRD patterns of SC, PEDOT, and PEDOT:SC. (d) UV–Vis absorption spectra of PEDOT:PSS and PEDOT:SC with different SC contents (solution concentration: 0.01 wt.%). (e) Zeta potentials of PEDOT:PSS and PEDOT:SC with varying SC contents. (f) Particle sizes of PEDOT:PSS and PEDOT:SC with different SC contents. (g) Photographs showing the storage stability of PEDOT:PSS and PEDOT:SC with different SC contents after 30 days at 4?°C. (h) Schematic illustration of the freeze-drying and redispersion process of PEDOT:SC. (i) Electrical conductivity of PEDOT:PSS and PEDOT:SC with varying SC contents.

  图3说明了以SC为聚合模板制备的PEDOT:SC 分散液展现优异稳定性和高导电性，冻干后仍可完全再分散，具有更广的应用范围。

Figure 4. (a) FTIR spectra of PEDOT:SC?/PAM hydrogels. (b) SEM image of the PEDOT:SC_1.5/PAM hydrogel. (c) EDS mapping image of the PEDOT:SC_1.5/PAM hydrogel. Stress–strain curves (d), Tensile strength and Young’s modulus (e), Toughness (f) of PAM and PEDOT:SC?/PAM hydrogels. (g) Cyclic tensile tests of the PEDOT:SC_1.5/PAM hydrogel under 50–400% strain. (h) Continuous cyclic loading-unloading curves of PEDOT:SC_1.5/PAM hydrogel at 200% strains. (i) Mechanical strength retention of PEDOT:SC_1.5/PAM hydrogel in the 50 loading-unloading cycles at 200% strains.

  图4说明了所得水凝胶可大幅拉伸并承受高应力，显示出卓越的韧性和强度。

Figure 5. (a) EIS spectra and (b) electrical conductivity of PAM and PEDOT:SC?/PAM hydrogels. (c) Temperature-dependent conductivity of the PEDOT:SC_1.5/PAM hydrogel. (d, e) Photographs showing an LED illuminated by the PEDOT:SC_1.5/PAM hydrogel at 25?°C and –20?°C, respectively. (f) Photographs of the PEDOT:SC_1.5/PAM hydrogel demonstrating flexibility, twisting, and stretching at –20?°C. (g) DSC curves of PEDOT:SC?/PAM hydrogels with different SC contents. (h) Stress–strain curves of the PEDOT:SC_1.5/PAM hydrogel at various temperatures. (i) Conductivity stability of the PEDOT:SC_1.5/PAM hydrogel after storage at –20?°C for 30 days.

  图5说明了该水凝胶具有良好的抗冻性能，即使在–20 °C下，水凝胶仍保持良好导电性和可拉伸性。

Figure 6. (a) Photographs of the PEDOT:SC_1.5/PAM hydrogel adhering to various substrates. (b) Schematic illustration of the peel–shear testing setup. (c) Shear adhesion curves of the hydrogel on different substrates. (d) Quantified adhesion strength. (e) Schematic illustration of the adhesion mechanisms between the hydrogel and various substrates.

  图6验证了水凝胶在多种基底上表现出强粘附性，可紧密贴附于皮肤、玻璃、金属等表面。

Figure 7. (a) Relative resistance variation ((R-R₀)/R₀) of the PEDOT:SC/PAM hydrogel versus consecutively applied strain underwater. (b) Real-time ((R-R₀)/R₀) of the PEDOT:SC/PAM hydrogel with different strains. (c) The resistance change curve for loading and unloading to 100% strain. (d) Response-recovery time of the obtained hydrogel upon stretching-releasing process at a fixed strain of 150%. (e) Relative-time ((R-R₀)/R₀) of the PEDOT:SC/PAM hydrogel on consecutive loading and unloading cycles at a 100% strain. Resistance changes during finger bending (f), elbow bending (g), and leg bending (h) were compared at 25°C and ?20°C. (i) Corresponding symbols of Morse code in the alphabet. (j, k) Special words such as “HELP” and “SOS” are generated by the output signals of the PEDOT:SC/PAM hydrogel sensor in emergency situations under 25°C. (l) Radar chart comparing the PEDOT:SC/PAM hydrogel sensor with previously reported hydrogel-based sensors in terms of electrical conductivity, mechanical flexibility, sensing performance (including fast response time and high GF), strong adhesion, and environmental adaptability.

  图7验证了水凝胶作为柔性应变传感器可灵敏检测人体动作信号，且在–20 °C 下依然稳定工作，通过弯曲水凝胶实现莫尔斯电码传输，展现其在极端环境下的应急通信潜力。

  该工作以“Tough, Adhesive, and Conductive Hydrogels Enabled by Stabilized PEDOT/Sulfated Cellulose Dispersions for Extreme-Temperature Sensing”为题发表在《Chemical Engineering Journal》上。

  中国林业科学研究院林产化学工业研究所博士研究生谢孝文为论文的第一作者，指导老师王基夫研究员和程增会博士为论文的通讯作者。该工作还得到了储富祥研究员和王春鹏研究员的支持和深刻指导，及中国林业科学研究院基金项目（CAFYBB2024QG001）和国家自然科学基金项目（32371822）的支持。

  原文链接：https://doi.org/10.1016/j.cej.2025.168658