Flory–Huggins VOC Photonics Sensor Made of Cellulose Derivatives

As a widespread air pollutant, volatile organic compounds (VOCs) are harmful to the human body’s skin, nervous system, and respiratory system. Low-cost, extensive, and continuous detection of VOCs is of great significance to human health. We infiltrated and coated cellulose acetate on the inverse opal photonic crystal skeleton of methylcellulose–polyvinyl alcohol–graphene oxide to construct a degradable, high-toughness cellulose VOC sensor. Cellulose acetate enhances the response to VOCs and achieves a highly selective response to acetone vapor due to the smaller Flory–Huggins parameter with acetone. This work proposes a general, simple, easy-to-use, and highly selective photonic crystal VOC sensor development strategy. Calculated from the Flory–Huggins solution theory, a suitable polymer was selected to modify the inverse opal photonic crystal framework and achieve high selectivity detection.