Entropy-stabilized single-atom Pd catalysts via high-entropy fluorite oxide supports

Xu, Haidi; Zhang, Zihao; Liu, Jixing; Do-Thanh, Chi-Linh; Chen, Hao; Xu, Shuhao; Lin, Qinjing; Jiao, Yi; Wang, Jianli; Wang, Yun; Chen, Yaoqiang; Dai, Sheng

doi:10.1038/s41467-020-17738-9

DOE OSTI · 1805021

Entropy-stabilized single-atom Pd catalysts via high-entropy fluorite oxide supports

Xu, Haidi·Zhang, Zihao·Liu, Jixing·Do-Thanh, Chi-Linh·Chen, Hao·Xu, Shuhao·Lin, Qinjing·Jiao, Yi·Wang, Jianli·Wang, Yun·Chen, Yaoqiang·Dai, Sheng

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Abstract

Single-atom catalysts (SACs) have attracted considerable attention in the catalysis community. However, fabricating intrinsically stable SACs on traditional supports (N-doped carbon, metal oxides, etc.) remains a formidable challenge, especially under high-temperature conditions. Here, we report a novel entropy-driven strategy to stabilize Pd single-atom on the high-entropy fluorite oxides (CeZrHfTiLa)O x (HEFO) as the support by a combination of mechanical milling with calcination at 900 °C. Characterization results reveal that single Pd atoms are incorporated into HEFO (Pd1@HEFO) sublattice by forming stable Pd–O–M bonds (M = Ce/Zr/La). Compared to the traditional support stabilized catalysts such as Pd@CeO 2 , Pd 1 @HEFO affords the improved reducibility of lattice oxygen and the existence of stable Pd–O–M species, thus exhibiting not only higher low-temperature CO oxidation activity but also outstanding resistance to thermal and hydrothermal degradation. This work therefore exemplifies the superiority of high-entropy materials for the preparation of SACs.

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Xu, Haidi, Zhang, Zihao, Liu, Jixing, Do-Thanh, Chi-Linh, Chen, Hao, Xu, Shuhao, Lin, Qinjing, Jiao, Yi, Wang, Jianli, Wang, Yun, Chen, Yaoqiang, Dai, Sheng. 2020-08-06. Entropy-stabilized single-atom Pd catalysts via high-entropy fluorite oxide supports. https://doi.org/10.1038/s41467-020-17738-9

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