State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, PR China.
State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, Changchun 130012, PR China.
J Colloid Interface Sci. 2019 Mar 1;537:520-527. doi: 10.1016/j.jcis.2018.11.030. Epub 2018 Nov 10.
Exploiting chemical sensors (CSs) with high-activity sensitive materials is very important for the detection of volatile organic compounds (VOCs). Co-containing spinel oxides are potential candidates for sensing layers. However, the intrinsic activity always hinders their further progress of sensing performances such as sensitivity and selectivity. Here, a facile strategy is successfully developed for the substitution of Co cations into Zn cations in CoO without sacrificing multi-shelled hollow structure. The synthesized cabbage-shaped ZnCoO exhibited the enhanced formaldehyde sensing capability compared to the CoO counterpart. The sensitivity to 100 ppm formaldehyde for ZnCoO-sensors is 7.4 at 180 °C, which is 6.2 times higher than that of CoO-sensors. In addition, the ZnCoO-sensors also show the fast response/recovery time (9/12 s) compared to CoO-sensors (55/63 s). Interestingly, Zn introduction can facilitate the accumulation of holes and generate more defective oxygen and adsorbed oxygen effectively. Consequently, remarkably improved sensitivity, selectively and fast response/recovery process are demonstrated for the ZnCoO-based sensors. The results offer crucial insights in realization of highly sensitive spinel oxide materials for CSs.
利用具有高活性敏感材料的化学传感器 (CSs) 对于检测挥发性有机化合物 (VOCs) 非常重要。含 Co 的尖晶石氧化物是传感层的潜在候选材料。然而，内在活性总是阻碍了它们在传感性能（如灵敏度和选择性）方面的进一步发展。在这里，成功开发了一种简便的策略，可将 Co 阳离子取代为 Zn 阳离子，而不会牺牲多壳空心结构。合成的白菜状 ZnCoO 与 CoO 相比表现出增强的甲醛传感能力。ZnCoO 传感器对 100ppm 甲醛的灵敏度在 180°C 时为 7.4，是 CoO 传感器的 6.2 倍。此外，ZnCoO 传感器的响应/恢复时间（9/12 s）也比 CoO 传感器（55/63 s）更快。有趣的是，Zn 的引入可以促进空穴的积累，并有效地产生更多的缺陷氧和吸附氧。因此，ZnCoO 基传感器表现出显著提高的灵敏度、选择性和快速响应/恢复过程。这些结果为 CSs 中实现高灵敏度尖晶石氧化物材料提供了重要的见解。
