Stabilizing Single-Atom Pt on Fe₂O₃ Nanosheets by Constructing Oxygen Vacancies for Ultrafast H₂ Sensing

Abstract

Single-atom catalysts (SACs) hold great promise in highly sensitive and selective gas sensors due to their ultrahigh atomic efficiency and excellent catalytic activity. However, due to the extremely high surface energy of SACs, it is still a huge challenge to synthesize a stable single-atom metal on sensitive materials. Here, we report an atomic layer deposition (ALD) strategy for the elaborate synthesis of single-atom Pt on oxygen vacancy-rich Fe 2 O 3 nanosheets (Pt−Fe 2 O 3 −V o ), which displayed ultrafast and sensitive detection to H 2 , achieving the stability of Pt single atoms. Gassensing investigation showed that the Pt−Fe 2 O 3 −V o materials enabled a significantly enhanced response of 26.5−50 ppm of H 2 , which was 17-fold higher than that of pure Fe 2 O 3 , as well as ultrafast response time (2 s), extremely low detection limit (86 ppb), and improved stability. The experimental and density functional theory (DFT) studies revealed that the abundant oxygen vacancy sites of Fe 2 O 3 contributed to stabilizing the Pt atoms via electron transfer. In addition, the stabilized Pt atoms also greatly promote the electron transfer of H 2 molecules to Fe 2 O 3 , thereby achieving an excellent H 2 sensing performance. This work provides a potential strategy for the development of highly selective and stable chemical sensors.

Unleashing the Potential of Single-Atom Nanozymes: Catalysts for the Future

“…Another big part is ensuring that SANs last long and are resistant during large-scale production processes . Knowing how stable these single-atom catalysts (SACs) are under different conditions is vital for their practical implementation in the industrial sector …”

Synergistic sensitization effects of single-atom gold and cerium dopants on mesoporous SnO2 nanospheres for enhanced volatile sulfur compound sensing

“…16,17 Therefore, the surface regulation of SMO sensing materials is crucial for achieving efficient sensing of target gases. 18–20 Noble metal single-atom catalysts (SACs) have attracted increasing attention for their ability to enhance the sensing performance via chemical and electronic sensitization effects. 21–26 Generally, SACs can significantly enhance the atomic utilization of noble metals and make full use of the active sites of noble metals.…”