The Dehydrogenation of H-S Bond into Sulfur Species on Supported Pd Single Atoms Allows Highly Selective and Sensitive Hydrogen Sulfide Detection
The Dehydrogenation of H-S Bond into Sulfur Species on Supported Pd Single Atoms Allows Highly Selective and Sensitive Hydrogen Sulfide Detection
复制标题
DOI：
10.1002/smll.202105643
复制
发表时间：
2021-10-29
期刊：
影响因子：
13.3
通讯作者：
Duan, Guotao
中科院分区：
文献类型：
--
作者：
Liu, Bo;Zhang, Linjuan;Duan, Guotao
支架上负载的金属催化剂通常具有多个活性中心，导致副反应的发生，不利于实现高一致性的催化。单原子催化剂（SACs）具有高度一致的单活性中心，具有很大的潜力来克服这些问题。在此，作者使用SACs来调节气敏反应的动力学过程。采用金属有机骨架模板法制备的负载型钯自组装活性炭对硫化氢气体具有很高的灵敏度和选择性，极大地提高了对硫化氢气体的检测能力。密度泛函理论计算表明，负载Pd的活性炭不仅增加了H2S分子向Pd活性炭的电子转移，而且增强了表面对H2S的亲合力.此外，吸附在Pd原子位置上的H2S分子的H-S键更可能直接脱氢成硫物种。值得注意的是，准原位XPS分析证实了在H2S检测过程中硫物种的存在，这可能是这种检测信号的主要原因。在此基础上，提出了一种适用于PdSAC驱动的H2S气体传感原理。这一工作将丰富催化电子学在化学电阻气体传感中的应用。
The supported metal catalysts on scaffolds usually reveal multiple active sites, resulting in the occurrence of side reaction and being detrimental to the achievement of highly consistent catalysis. Single atom catalysts (SACs), possessed with highly consistent single active sites, have great potentials for overcoming such issues. Herein, the authors used SACs to modulate kinetic process of gas sensitive reaction. The supported Pd SACs, established by a metal organic frameworks-templated approach, promoted greatly the detection capacity to hydrogen sulfide (H2S) gas with a very high sensitivity and selectivity. Density functional theory calculations show that the supported Pd SACs not only increased the number of electrons transferring from H2S molecules to Pd SACs, but strengthened surface affinity to H2S. Moreover, the H-S bonds of H2S molecules absorbed on Pd atomic sites are more likely to be dehydrogenated directly into sulfur species. Significantly, quasi in situ XPS analysis confirmed the presence of sulfur species during H2S detection process, which may be a major cause for such detection signal. Based on these results, a suitable sensing principle for H2S gas driven by Pd SACs was put forward. This work will enrich catalytic electronics in chemiresistive gas sensing.