PdPt Bimetal-Functionalized SnO2 Nanosheets: Controllable Synthesis and its Dual Selectivity for Detection of Carbon Monoxide and Methane
PdPt Bimetal-Functionalized SnO2 Nanosheets: Controllable Synthesis and its Dual Selectivity for Detection of Carbon Monoxide and Methane
复制标题
PdPt 双金属功能化 SnO2 纳米片：可控合成及其用于检测一氧化碳和甲烷的双重选择性
DOI：
10.1021/acsami.9b08408
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发表时间：
2019-07-24
影响因子：
9.5
通讯作者：
Xu, Jiaqiang
中科院分区：
文献类型：
--
作者：
Li, Gaojie;Wang, Xiaohong;Xu, Jiaqiang
双金属纳米粒子由于其独特的协同效应而表现出许多新颖的性质，在气敏领域有着重要的应用前景。成功地合成了具有富Pd壳和富Pt核的PdPt双金属纳米粒子，并用于修饰SnO 2纳米片。通过PdPt NPs的自组装获得的1 P-PdPt/SnO 2-A传感器在100 ° C下对CO和在320 ° C下对CH 4表现出温度依赖的双重选择性。该传感器具有良好的长期稳定性和抗湿度干扰能力。利用Langmuir吸附动力学模型，通过温度响应过程估算了CO和CH 4的吸附活化能，证明吸附活化能越低，传感性能越好。根据被测气体在敏感层中的扩散深度，探讨了其气敏机理。PdPt纳米颗粒的高催化活性、PdO的电子敏化作用以及SnO 2和PdPt纳米颗粒界面处的肖特基势垒型结是传感性能显著提高的主要原因。我们目前的研究结果表明，具有特殊结构和组分的纳米颗粒可以显着提高金属氧化物半导体的气敏性能，所获得的传感器在煤矿瓦斯监测中具有很大的潜力。
Bimetallic nanoparticles (NPs) usually exhibit some novel properties due to the synergistic effects of the two distinct metals, which is expected to play an important role in the field of gas sensing. PdPt bimetal NPs with Pd-rich shell and Pt-rich core were successfully synthesized and used to modify SnO2 nanosheets. The 1P-PdPt/SnO2-A sensor obtained by self-assemblies of PdPt NPs exhibited temperature-dependent dual selectivity to CO at 100 degrees C and CH4 at 320 degrees C. Furthermore, the sensor possessed good long term stability and antihumidity interference. The activation energy of adsorption for CO and CH4 were estimated by the temperature-dependent response process modeled using Langmuir adsorption kinetics, which proved that the lower activation energy of adsorption corresponded to better sensing performance. The gas-sensing mechanism based on the diffusion depth of the tested gas in the sensing layer was discussed. The dramatically improved sensing performance could be ascribed to the high catalytic activity of PdPt bimetal, the electron sensitization of PdO, and Schottky barrier-type junctions at the interface between SnO2 and PdPt NPs. Our present results demonstrate that bimetal NPs with special structure and components can significantly improve the gas-sensing performance of metal oxide semiconductor and the obtained sensor has great potential in monitoring coal mine gas.