Metal–support interaction-modulated catalytic activity of Ru nanoparticles on Sm2O3 for efficient ammonia decomposition

Abstract

Development of efficient catalysts is important for production of CO_x-free hydrogen from ammonia decomposition. Herein, a highly active catalyst with uniform Ru nanoparticles dispersed on Sm₂O₃ nanorods is developed via a facile precipitation method. Under a relatively high weight hourly space velocity of 30 000 mL g⁻¹ h⁻¹, Ru/Sm₂O₃ can catalyze ammonia decomposition reaction with a H₂ formation rate as high as 25.9 mmol g_cat⁻¹ min⁻¹ at 450 °C, which is superior to most of conventional oxide-supported Ru catalysts. Moreover, we find that the activity of Ru/Sm₂O₃ is highly dependent on the preparation method. The Ru/Sm₂O₃ catalyst prepared by precipitation method exhibits much higher activity than the Ru/Sm₂O₃ analogues by impregnation and solid milling methods. Characterization results demonstrate that the superior catalytic performance of Ru/Sm₂O₃ achieved from precipitation method should originate from much enhanced interaction between Ru nanoparticles and Sm₂O₃ support. These findings offer promise to explore Ru/Sm₂O₃ catalyst as a new kind of efficient catalyst for ammonia decomposition and to improve the catalytic performance by modulating the metal–support interaction of the catalyst.