PtFeCoNiCu High-Entropy Alloy Catalyst for Aqueous-Phase Hydrogenation of Maleic Anhydride
Nannan Zhang1, Xiao Chen1, Shiyao Liu1
1State Key Laboratory of Fine Chemicals, Laboratory of Advanced Materials and Catalytic Engineering, School of Chemical Engineering, Dalian University of Technology, Dalian 116024, China.
Abstract:
High-entropy alloys (HEAs), as new heterogeneous catalytic materials, possess remarkable catalytic performance in numerous reactions. However, rational and controllable synthesis of these complex structures remains a challenge. In this work, bulk and carbon nanotube (CNT)-supported ultrasmall PtFeCoNiCu HEA nanoparticles with an average particle size of 1.58 nm are prepared by lithium naphthalenide-driven reduction under mild conditions. The supported PtFeCoNiCu/CNT catalyst exhibits high catalytic activity in the aqueous-phase hydrogenation of maleic anhydride to succinic acid with a selectivity of 98% at full conversion of maleic acid (the hydrolysis product of maleic anhydride), a low apparent activation energy (Ea = 49 kJ mol-1), and excellent stability. Moreover, a much higher mass-specific activity of Pt in the catalyst is displayed over PtFeCoNiCu/CNT (1515.4 mmolmaleic acid gPt-1 h-1) than that of 5 wt % Pt/CNT (388.0 mmolmaleic acid gPt-1 h-1). This work provides a strong support for HEAs as advanced heterogeneous catalysts and will be of great significance for promoting the research and application of HEAs in the field of selective hydrogenation.
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