Details

Autor(en) / Beteiligte

• Zhu, Chao
• Yao, Yanchi
• Fang, Qile
• Song, Shuang
• Chen, Baoliang
• Shen, Yi

Titel

Unveiling the Dynamic Evolution of Single-Atom Co Sites in Covalent Triazine Frameworks for Enhanced H2O2 Photosynthesis

Ist Teil von

• ACS catalysis, 2024-03, Vol.14 (5), p.2847-2858

Ort / Verlag

American Chemical Society

Erscheinungsjahr

2024

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Unraveling the structural evolution and mechanism of active sites in single-atom catalysts (SACs) during H2O2 production under operational conditions remains challenging due to the transient and elusive nature of the underlying reaction processes. Herein, we employ operando X-ray absorption spectroscopy and ab initio molecular dynamics simulations to unveil the dynamic reconstruction behavior of the Co single atom-loaded covalent triazine framework (CoSA/Py-CTF) during photocatalytic H2O2 production. The unique Py-CTF substrate provides reasonable structural flexibility to the single atom Co site. Under light irradiation and O2 adsorption, single Co atoms are dynamically released from the Py-CTF substrate and then form transient atom-pairs with neighboring Co atoms, serving as the authentic active site. The dynamic shuttling of Co subnanometer domains between single-atoms and atom-pairs facilitates the transition of the O2 adsorption configurations from Pauling type to Yeager type, resulting in a record photocatalytic H2O2 yield (2898.3 μmol·h–1·g–1). These findings provide insightful observations into the dynamic photochemical behavior of SACs and present an fresh paradigm for the design of intelligent “adaptive catalysts”.