Synthesis of Au/Ce₂S₃@CeO₂/CuS nanocomposites for promoted catalytic performance in propargylamine conversion

 Y. Pan, J. Yang, H. Feng, S. Cao, X. Zheng, G. Rupprechter, Y. Deng, J. Wang, 

Applied Surface Science, 681 (2025) 161559.  https://doi.org/10.1016/j.apsusc.2024.161559

Highlights

• •Au/Ce₂S₃@CeO₂/CuS nanocatalysts were prepared for propargylamine synthesis.
• •Ce₂S₃ was converted by CeO₂ in Na₂S due to the different solubility product constant.
• •Contents of active sites Cu⁺ and Ce³⁺ were highly improved in Au/Ce₂S₃@CeO₂/CuS.
• •A high product conversion rate of 222.5 mmol·g⁻¹·h⁻¹ obtained for Au/Ce₂S₃@CeO₂/CuS.
• •Au/Ce₂S₃@CeO₂/CuS also showed excellent recyclability, with 80 % retention after 5 cycles.

Abstract

A newly developed nanocomposite catalyst, Au/Ce₂S₃@CeO₂/CuS, has been engineered for effective propargylamine synthesis through the A³ coupling reaction. The catalyst’s synthesis involved the targeted addition of 15 wt% CeO₂ to the CuS sulfur precursor, leading to the formation of a Ce₂S₃ layer due to its lower solubility product constant (K_sp). This layer, along with 0.5 wt% Au nanoparticles, significantly increased the Ce³⁺ concentration (16.9 % to 33 %–52 %), which can accelerate the Cu⁺/Cu²⁺ valence state changes, thereby promoting the activation of the alkynyl hydrogen to enhance propargylamine formation. After 2 h reaction, the Au/Ce₂S₃@CeO₂/CuS catalyst achieved over 99 % conversion, nearly 55 % more than pure CuS (45.5 %). The Au/Ce₂S₃@CeO₂/CuS nanocomposite also showed excellent recyclability (80 % retention after 5 cycles) and a high conversion rate of 222.5 mmol·g⁻¹·h⁻¹.

Graphical abstract