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

Abstract

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 H 2 S 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 H 2 S on Pt and the electronic transformation process on Ru, which can be proved by ex situ X-ray photoelectron spectroscopy experiments. Notably, a special crosslinkable 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 H 2 S 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.

Redispersing Ir Nanoparticles via a Carbon-Assisted Pyrolysis Process to Break the Activity–Stability Trade-Off of H2 Sensors

“…The above changes represent that more oxygen species are reduced, thereby accelerating the H 2 redox reaction progression on the Ir red /ZnO-450 surface. The peaks of the H 2 -TPR profile can be attributed to the reduction of adsorbed oxygen species, surface or bulk lattice oxygen atom, and metal atom by H 2 . The Ir red /ZnO-450 material exhibits a significant H 2 consumption peak at 120 °C driven by reactive oxygen species (Figure g).…”

MoO2 Pump-Enhanced Flexible TiO2 Nanojungle-Based Chemiresistors for Rapid Room-Temperature Detection of H2S at Parts-per-Billion Levels

“…Moreover, H 2 S reacts with O 2 – on the active sites of the C 3 N 4 /TiO 2 interface, further consuming the depletion layer. The corresponding reaction is illustrated in eq 2 H 2 normalS + 3 O 2 − → 2 SO 2 + 2 H 2 normalO + 3 e − …”