Prof. Chao WANG

Guangdong Provincial Key Laboratory on Functional Soft Condensed Matter, School of Materials and Energy, Guangdong University of Technology, China

E-mail: chaowang@gdut.edu.cn

Bio

Dr. Chao WANG is a Professor from Guangdong University of Technology, serving as an assistant to the Dean and deputy director of the "Guangdong Provincial Key Laboratory on Functional Soft Condensed Matter";  engaged in research related to high entropy catalyst development and hydrogen energy development and utilization, presided over various scientific research projects including the National Natural Science Foundation of China, published over 150 peer reviewed academic papers.

Title

High-entropy Catalyst for Efficient and Stable Steam Reforming towards Low-Carbon Hydrogen Production

Abstract

The heterophase interface between the catalyst and the high-temperature CxHyOz/H2O mixture heat flow constitutes the heat exchange boundary in steam reforming. Consequently, catalysts inevitably experience significant temperature gradients, leading to degradation via active metal nanoparticle agglomeration and reduced energy utilization. High-entropy oxides (HEOs), known for their unique core effects, are promising candidates for novel high-temperature catalysts. However, leveraging their unique features for efficient hydrogen production via steam reforming remains unexplored. This work reports a high-entropy perovskite catalyst synthesized via a wet-chemical process, demonstrating outstanding stability under the redox conditions of high-temperature reforming. Intriguingly, self-reconstruction of the HEO was observed during the initial reaction stage, proving crucial for efficient H₂ production. Driven by lattice distortion, active surface oxygen species reacted with hydrogen carrier molecules via redox processes, inducing surface reconstruction. DFT calculations and HAADF-STEM revealed that, facilitated by polymetallic synergy, dynamic redistribution of active components formed a supported-like NiCo/HEO structure. This structural evolution correlated with an increasing H₂ production rate. Exsolved NiCo nanoparticles (~20 nm) stably embedded into the HEO surface, forming a "semi-embedded-exposed" heterointerface that effectively prevented agglomeration. This ensured long-term stability (>1200 min) under severe thermal stress and redox cycling at 800 °C. Furthermore, the sluggish diffusion effect at the metal-support interface delayed heat release at active sites, providing energy input that facilitated rapid C-H/O-H bond cleavage and efficient hydrogen production under photothermal drive. This work elucidates the catalytic mechanism of HEOs and provides valuable insights for developing stable high-temperature catalysts for H₂ production.