Zito Cecilia A, Perfecto Tarcísio M, Dippel Ann-Christin, Volanti Diogo P, Koziej Dorota
Laboratory of Materials for Sustainability (LabMatSus), São Paulo State University (UNESP), Rua Cristóvão Colombo 2265, 15054000 São José do Rio Preto, Brazil.
Center for Hybrid Nanostructures (CHyN), Institute of Nanostructure and Solid State Physics, University of Hamburg, Luruper Chaussee 149, 22607 Hamburg, Germany.
ACS Appl Mater Interfaces. 2020 Apr 15;12(15):17745-17751. doi: 10.1021/acsami.0c01641. Epub 2020 Apr 6.
Monitoring carbon dioxide (CO) levels is extremely important in a wide range of applications. Although metal oxide-based chemoresistive sensors have emerged as a promising approach for CO detection, the development of efficient CO sensors at low temperature remains a challenge. Herein, we report a low-temperature hollow nanostructured CeO-based sensor for CO detection. We monitor the changes in the electrical resistance after CO pulses in a relative humidity of 70% and show the high performance of the sensor at 100 °C. The yolk-shell nanospheres have not only 2 times higher sensitivity but also significantly increased stability and reversibility, faster response times, and greater CO adsorption capacity than commercial ceria nanoparticles. The improvements in the CO sensing performance are attributed to hollow and porous structure of the yolk-shell nanoparticles, allowing for enhanced gas diffusion and high specific surface area. We present an easy strategy to enhance the electrical and sensing properties of metal oxides at a low operating temperature that is desirable for practical applications of CO sensors.
监测二氧化碳（CO）水平在广泛的应用中极其重要。尽管基于金属氧化物的化学电阻传感器已成为检测CO的一种有前景的方法，但开发高效的低温CO传感器仍然是一项挑战。在此，我们报道了一种用于CO检测的低温中空纳米结构CeO基传感器。我们在70%相对湿度下监测CO脉冲后电阻的变化，并展示了该传感器在100°C时的高性能。与商业二氧化铈纳米颗粒相比，蛋黄壳纳米球不仅灵敏度高2倍，而且稳定性、可逆性显著提高，响应时间更快，CO吸附能力更强。CO传感性能的改善归因于蛋黄壳纳米颗粒的中空和多孔结构，这使得气体扩散增强且比表面积增大。我们提出了一种简单的策略，可在低工作温度下增强金属氧化物的电学和传感性能，这对于CO传感器的实际应用是非常理想的。
