Hierarchical porous triboelectric aerogels enabled by heterointerface engineering

Abstract

The concept of the "Internet of Things" has made smart materials essential for sensing, responding to, and adapting to real-time feedback from the external environment. Cellulose aerogels hold immense potential in the field of smart triboelectric materials. However, conventional cellulose aerogels often face issues such as structural fragility, which limits their potential as smart materials. In this study, a compressible cellulose triboelectric aerogel with a hierarchical porous structure was prepared through heterointerface engineering. By introducing a heterointerface between oxidized cellulose nanofibers (TCNF) and carbon nanotubes (CNT), the structural stability of the material was significantly improved. The aerogel exhibited a 40-fold improvement in compressive performance and demonstrated excellent porosity (97.23%). A triboelectric nanogenerator was constructed using this material to explore its potential as a smart material. Experimental results indicated that the aerogel exhibited high sensitivity to ammonia gas, accurately identifying variations in NH3 concentration within the range of 20–150 ppm, with excellent linearity (R2 =0.996). Moreover, utilizing this triboelectric gas sensor as a wireless sensing terminal in smart devices enabled successful real-time wireless detection of food spoilage processes. This research provides new insights into the development of smart materials made from aerogels and has significant research and practical value for expanding the utilization of cellulose-based aerogels.