Designing functional filler networks via in situ silver nanoparticles through barrier tuning and volume exclusion

作者：Ke Tian, Jianwei Jing, Ming Wen, Liping Zhang, Qianyang Li, Minhan Cheng, Jie Wen, Yiming Wen, Yong Wen, Qiang Fu, Hua Deng · 发表于：Nature Communications · 年份：2025 · DOI：10.1038/s41467-025-67461-6 · 被引用次数：7 · 研究领域：Nanomaterials and Printing Technologies、Advanced Sensor and Energy Harvesting Materials、Thermal properties of materials

The fabrication of high-performance functional polymer composites requires delicate balance between functionalities, filler content and overall performance, and preparation route is urgently needed. Guided by Simmons theory, a PDMS-based stretchable conductor with metal-level conductivity is realized through a strategy by combining silver nanoparticle in-situ formation, optimized barrier height and volume excluding effect. Firstly, a universal matrix-independent etching-reduction method generates uniform Ag nanoparticles (~ 9.7 nm), shortening tunneling distances. Then, tunneling barrier height is minimized to 0.06 eV by aligning energy levels of surface-treated silver nanoflakes and PDMS, reducing electron scattering. Finally, silver-plated PDMS microspheres act as volume-excluding phase, compressing tunneling widths below the critical threshold (<10 nm). This integrated approach yields exceptional electrical conductivity (29429 S/cm) at 50 wt% Ag loading. Such tunneling networks retain 53% conductivity at 100% strain, while thermal conductivity increases from 4.3 to 24.3 W/m·K. This work demonstrates rational quantum tunneling barrier control to overcome performance trade-offs, providing a design framework for advanced conductive composites.