Ling Zhang, Xingmao Chang*, Zebiao Qiu, Ruijuan Wen, Zhongrun Kang, Chenxi Zhang, Qianhua Liu, Xuepeng Zhang, Haonan Peng*, and Yu Fang. Sci. China Chem. 2025. DOI: 10.1007/s11426-025-2816-3

Flexible functional materials hold broad potential in portable electronics, sensing, and environmental monitoring. However, the simultaneous realization of high mechanical strength, excellent flexibility, and multi-stimuli responsiveness remains a significant challenge. Conventional organic–inorganic composites or polymer-doping strategies often suffer from inevitable trade-offs in performance. In contrast, gas–liquid interfacial chemistry has attracted increasing attention because it enables the scalable construction of thin films with controllable thickness and uniform structures. By introducing dynamic covalent bonds into the system, the resulting films gain reversible responsiveness and environmental adaptability, along with enhanced structural stability and functional integration.

In this work, we develop a dynamic covalent self-assembly strategy at the humid air/dimethyl sulfoxide interface, employing polyethylene glycol (PEG) segments as flexible linkers to the luminescent building blocks. This design simultaneously improves the mechanical strength, flexibility, and responsiveness of the films to organic vapors and humidity. The as-prepared films exhibit excellent stretchability and anisotropic morphology, with the air-exposed surface forming a distinctive porous network that markedly enhances the fluorescence sensitivity toward the sarin simulant diisopropyl chlorophosphate (DCP). This study demonstrates a rational approach to balancing mechanical performance with multi-stimuli responsiveness, offering new insights into the design of high-performance functional thin films for intelligent materials and environmental monitoring applications.

Figure 1. (a) Monomers. (b) Schematic diagram of the preparation process of the film based on the gas-liquid interface confined dynamic condensation strategy. (c) Schematic diagram of the film structure. (d) Basic properties of the film.

Figure 2. Investigation of the film's mechanical properties.

Figure 3. Analysis of sensing test results based on the stacked film sensor platform.

First Author: Zhang Ling, master’s student, Shaanxi Normal University

Correspondence Authors: Prof. Peng Haonan, Shaanxi Normal University; Dr. Chang Xingmao, University of Ulm

Full Text Link: http://engine.scichina.com/doi/10.1007/s11426-025-2816-3