标题： 具有先进降解稳定性和空气中电子性能控制的三维多孔MXene/PNIPAAm水凝胶复合材料 显示英文标题

标题： A 3D porous MXene/PNIPAAm hydrogel composite with advanced degradation stability and control of electronic properties in air

摘要： 本研究报告了一种由MXene（Ti$_3$C$_2$T$_x$）和刺激响应性水凝胶（聚(N-异丙基丙烯酰胺）- PNIPAAm）组成的新型复合材料的基本研究。与之前报道的MXene和水凝胶的结合方式不同，此处描述的材料为挥发性有机化合物（VOC）传感提供了一个可调的多孔结构，在任何气体环境和干燥状态下都能保持其稳定性和响应性。此外，与其他关于多孔MXene复合材料的研究相比，该材料的合成方法显著更简单且更高效。本研究重点是对合成的MXene/PNIPAAm复合材料的特性进行基础研究。通过制备和比较纯MXene和具有致密或高度多孔三维微结构的复合样品，揭示了以下独特性质：（i）MXene的可控三维空间排列，而非普遍存在的堆叠片状结构；（ii）MXene氧化引起的降解减少，并在三个月内显著增强了稳定性；（iii）对气体相互作用的可调电子状态。材料表征通过扫描电子显微镜和流变学进行，以评估微观结构和机械性能，并在化学电阻测量设置中确定电性能，评估复合材料在含有测试分析物丙酮的气体环境中用于VOC传感的潜力。这些研究揭示了基本的新型材料效应和特性，解决了部分与MXene相关的关键挑战。此外，MXene和水凝胶之间的相互作用为增强刺激响应性水凝胶的传感潜力提供了前所未有的机会，特别是在气体环境中。 显示英文摘要

摘要： This study reports the fundamental investigation of a novel composite material consisting of MXene (Ti$_3$C$_2$T$_x$) and a stimulus-responsive hydrogel (Poly(N-isopropylacrylamide) - PNIPAAm). In contrast to previously reported integration of MXene and hydrogels, the material described here offers a tunable porous structure for volatile organic compound (VOC) sensing that maintains its stability and responsiveness in any kind of gaseous environment and in a dried state. Furthermore, its synthesis is significantly simpler and more efficient compared to other studies on porous MXene composites. The presented study focuses on a fundamental investigation of the synthesized MXene/PNIPAAm composite's properties. Thereby, the fabrication and comparison of pure MXene and composite samples featuring either a compact or a highly porous three-dimensional microstructure, reveal unique properties with respect to: (i) controllable three-dimensional spatial arrangement of MXene instead of the prevalent stacked-sheet structure, (ii) reduction of oxidation-induced degradation of MXene and substantially enhanced stability over the course of three months, and (iii) tunable electronic states in response to gas interactions. Material characterization is conducted by scanning electron microscopy and rheology to assess the microstructural and mechanical properties, and in a chemiresistive measurement setup for determination of electrical properties and the evaluation of the composite's potential for VOC sensing in a gaseous environment with the test analyte acetone. These investigations reveal fundamentally novel material effects and properties that address some of the key MXene-related challenges. Additionally, the interplay between the MXene and the hydrogel enables unprecedented opportunities for enhancing the sensing potential of stimulus-responsive hydrogels, specifically in gaseous environments.