Three‐dimensional CeO <sub>2</sub> @carbon‐quantum‐dots scaffold modified with Au nanoparticles on flexible substrates for high performance gas sensing at room temperature
Chao Wang, Long Zhang, Bing He, Quan Zhou, Shaohui Zhang, Xiu-Li Kong, Zhen Chen, Ge‐Bo Pan
Abstract
Abstract High‐performance gas sensing materials operated at room temperature (RT) are attractive for a variety of real‐time gas monitoring applications, especially with the excellent durability and flexibility of wearable sensor. The constructing heterostructure is one of the significant approaches in design strategies of sensing materials. This heterostructure effectively increases the active site for improving sensing performance and decreasing energy consumption. Herein, the heterostructure of Au nanoparticles modified CeO 2 @carbon‐quantum‐dots (Au/CeO 2 @CQDs) with a three‐dimensional (3D) scaffold structure are successfully synthesized by an effective strategy, which can apply for preparing flexible gas sensor. The gas sensing properties of Au/CeO 2 @CQDs based on flexible substrate are obtained under long‐term repeated NO 2 exposure at RT. Meanwhile, the long‐term mechanical stability of this gas sensing device is also detected after different bending cycles. The Au/CeO 2 @CQDs based on flexible substrate sensor exhibits excellent performance, including higher sensitivity (47.2), faster response (18 s) and recovery time (22 s) as well as longer‐term stability than performance of pure materials. The obtained sensor also reveals outstanding mechanical flexibility, which is only a tiny response fluctuation (8.1%) after 500 bending/relaxing cycles. Therefore, our study demonstrates the enormous potential of this sensing materials for hazardous gas monitoring in future portable and wearable sensing platform.