Yinchao Xu

1 Introduction Ultrasensitive and reliable gas-phase chemical sensors are critically needed for applications ranging from environmental monitoring and industrial safety to defense and security. They also play a central role in the exposome framework, which emphasizes comprehensive measurement of environmental exposures across the human lifespan [1]. Achieving part-per-trillion (ppt) sensitivity under real-world conditions is particularly important for early warning and exposure prevention.

1. Introduction Cellulosic raw materials originate from diverse sources and offer notable advantages, including biocompatibility, degradability, and renewability. The remarkable potential of cellulose has garnered significant attention from researchers worldwide, driving the exploration and development of numerous cellulose-based materials. Of particular interest among these cellulose-based materials are cellulose aerogels, distinguished by their unique three-dimensional porous network structure.