Abstract
Organosilicon polymers were deposited on Quartz Crystal Microbalance (QCM) supports using Plasma‐Enhanced Chemical Vapor Deposition (PECVD) with a cyclic injector. By tuning plasma power and precursor flux, film structure was optimized for toluene sorption. A key outcome is the establishment of non‐trivial correlations between the chemical structure and textural properties of the films and their toluene sorption behavior. Depending on these parameters, films exhibited either glassy or rubbery sorption profiles. Soft plasma conditions yielded rubbery‐like films with high toluene sensitivity, full reversibility, and promising selectivity, remaining unaffected by water vapor. These findings demonstrate that fine control over PECVD conditions facilitates the rational design of high‐performance sensing layers for selective VOC detection and enhanced Indoor Air Quality management.