Key Laboratory of Comprehensive and Highly Efficient Utilization of Salt Lake Resources, Qinghai Engineering and Technology Research Center of Comprehensive Utilization of Salt Lake Recources, Qinghai Institute of Salt Lake, Chinese Academy of Sciences, Xining 810008, China.
Dalton Trans. 2018 Nov 21;47(43):15331-15337. doi: 10.1039/c8dt01980k. Epub 2018 Sep 12.
The loading of noble-metal nanoparticles (NPs) is an effective approach for the enhancement of H sensing performances, although there have been rare reports focused on the effect of the facets of noble-metal nanoparticles in the H sensing performance. The catalytic and adsorption performance of noble-metal nanocrystals is mainly determined by their exposed facets, while the gas sensing performance of sensors is strongly correlated to the adsorption and reaction between the gases and sensor materials. Hence, it is very important to study the gas sensing performance of the different facets-exposed noble-metal nanoparticles. In this study, a set of shape-controlled Pd NPs have been prepared and loaded onto the ZnO nanorods, and the gas sensing performance of the Pd nanoparticle-loaded ZnO to 250 ppm of H has been detected. The results indicate that the cubic Pd NPs-loaded ZnO shows higher and faster sensing response to H than the octahedral and spherical Pd-loaded ZnO owing to the stronger adsorption of the H by cubic Pd NPs enclosed by (100) facets than the octahedral NPs enclosed by (111) facets. The cubic Pd NPs-loaded ZnO also exhibits better sensing selectivity and repeatability towards H.
负载贵金属纳米粒子（NPs）是增强 H 传感性能的有效方法，尽管很少有报道关注贵金属纳米粒子的晶面效应对 H 传感性能的影响。贵金属纳米晶的催化和吸附性能主要取决于其暴露的晶面，而传感器的气体传感性能与气体和传感器材料之间的吸附和反应密切相关。因此，研究不同晶面暴露的贵金属纳米粒子的气体传感性能非常重要。在本研究中，制备了一组形状可控的 Pd NPs 并负载到 ZnO 纳米棒上，并检测了 Pd 纳米粒子负载的 ZnO 对 250ppm H 的气体传感性能。结果表明，由于（100）面封闭的立方 Pd NPs 对 H 的吸附强于（111）面封闭的八面体 NPs，因此负载立方 Pd NPs 的 ZnO 对 H 的传感响应更高、更快。负载立方 Pd NPs 的 ZnO 对 H 还表现出更好的传感选择性和重复性。
