A polydiacetylene-based smart cellulose aerogel functionalized by ZnO/MoS2 heterojunction for simultaneous visual detection and photocatalytic degradation of gaseous VOCs

The integration of visual detection and degradation of volatile organic compounds (VOCs) is greatly desired for addressing ever-growing environmental problems. Herein, a chemically cross-linked cellulose aerogel is explored as substrate material, combing with ZIF-8/MoS2 derived 2D ZnO/MoS2 heterojunction. Then polydiacetylene (PDA) was self-assembled on the aerogel via topochemical polymerization to obtain a smart gas sensing and eliminating hybrid aerogel (PZMCA) with high porosity (>96%). The intrinsic stimulate responsiveness and the flower-like hierarchical structure of PDA contributed to a sensitive and fast color response to gaseous toluene with 10 s. Moreover, by regulating the mass ratio of ZnO and MoS2, the PZMCA presented enhanced photocatalytic ability for toluene (97% of degradation efficiency with 180 min) under solar light irradiation. GC-MS reveals the possible mechanism and pathway of the photocatalytic degradation of toluene. The robust, uniform, versatile and functional aerogels could hopefully provide practical applications in VOCs detection and photocatalytic degradation.

Automated summary

In this study, a smart gas sensing and eliminating hybrid aerogel (PZMCA) with high porosity was developed by self-assembling polydiacetylene (PDA) on a chemically cross-linked cellulose aerogel, combined with 2D ZnO/MoS2 heterojunction derived from ZIF-8/MoS2. The PZMCA showed a sensitive and fast color response to gaseous toluene and exhibited enhanced photocatalytic degradation efficiency for toluene under solar light irradiation.