Highly selective gas sensors for formaldehyde detection based on ZnO@ZIF‑8 core-shell heterostructures
Publication Name
Sensors and Actuators B: Chemical
Abstract
Formaldehyde is a hazardous volatile organic pollutant commonly found indoors, making selective and accurate detection of formaldehyde crucial. To achieve this, ZnO@ZIF-8 core-shell heterostructures were fabricated using the sacrificial template method, where the 3D ZnO flower-like structures served as the core material. This innovative approach utilizing the ZIF-8 shell as a “selective gas filter” offers a novel pathway for enhancing the selectivity of formaldehyde sensors. Subsequent investigations revealed that the thickness of the ZIF-8 shell significantly influences the material's performance. Among various configurations tested, the 2-ZnO@ZIF-8 sensor demonstrates the best formaldehyde detection properties, including high response (5 ppm, 5.03), excellent selectivity, short response and recovery times (29/40 s), excellent long-term stability, and a low theoretical detection limit (12.86 ppb) at 175 °C. The enhanced sensing properties can be attributed to the ZIF-8 surface's high adsorption energy for formaldehyde molecules and the selective screening of gas molecules by ZIF-8. Overall, our study presents a promising strategy for developing highly selective gas sensors for formaldehyde detection, with the potential to contribute to improved indoor air quality monitoring and safety measures.
Open Access Status
This publication is not available as open access
Volume
398
Article Number
134689
Funding Number
LJKMZ20220762
Funding Sponsor
National Natural Science Foundation of China