Engineering a Heterophase Interface by Tailoring the Pt Coverage Density on an Amorphous Ru Surface for Ultrasensitive H2S Detection

• Published in: ACS sensors Vol. 8; no. 6; pp. 2237 - 2246
• Main Authors: Luo, Na, Guo, Mengmeng, Cai, Haijie, Li, Xiaojie, Wang, Xiaohong, Cheng, Zhixuan, Xue, Zhenggang, Xu, Jiaqiang
• Format: Journal Article
• Language: English
• Published: American Chemical Society 23.06.2023
• Subjects: amorphous/crystalline heterophase; heterophase engineering; bimetal sensitizer; H2S detection; cross-linkable coverage 3cPt/aRu
• ISSN: 2379-3694; 2379-3694
• DOI: 10.1021/acssensors.3c00215

Amorphous/crystalline heterophase engineering is emerging as an attractive strategy to adjust the properties and functions of nanomaterials. Here, we reveal a heterophase interface role by precisely tailoring the crystalline Pt coverage density on an amorphous Ru surface (cPt/aRu) for ultrasensitive H2S detection. We found that when the atomic ratio of Pt/Ru increased from 10 to 50%, the loading modes of Pt changed from island coverage (1cPt/aRu) to cross-linkable coverage (3cPt/aRu) and further to dense coverage (5cPt/aRu). The differences in coverage models further regulate the chemical adsorption of H2S on Pt and the electronic transformation process on Ru, which can be proved by ex situ X-ray photoelectron spectroscopy experiments. Notably, a special cross-linkable coverage 3cPt/aRu on ZnO shows the best gas-sensitive performance, in which the operating temperature reduces from 240 to 160 °C compared with pristine ZnO and the selectivity coefficient for H2S gas improves from ∼1.2 to ∼4.6. This is mainly benefit from the maximized exposure of the amorphous/crystalline heterophase interface. Our work thus provides a new platform for future applications of amorphous/crystalline heterogeneous nanostructures in gas sensors and catalysis.