Yao Yonggang, Huang Zhennan, Xie Pengfei, Wu Lianping, Ma Lu, Li Tangyuan, Pang Zhenqian, Jiao Miaolun, Liang Zhiqiang, Gao Jinlong, He Yang, Kline Dylan Jacob, Zachariah Michael R, Wang Chongmin, Lu Jun, Wu Tianpin, Li Teng, Wang Chao, Shahbazian-Yassar Reza, Hu Liangbing
Department of Materials Science and Engineering, University of Maryland, College Park, MD, USA.
Department of Mechanical and Industrial Engineering, University of Illinois at Chicago, Chicago, IL, USA.
Nat Nanotechnol. 2019 Sep;14(9):851-857. doi: 10.1038/s41565-019-0518-7. Epub 2019 Aug 12.
The stability of single-atom catalysts is critical for their practical applications. Although a high temperature can promote the bond formation between metal atoms and the substrate with an enhanced stability, it often causes atom agglomeration and is incompatible with many temperature-sensitive substrates. Here, we report using controllable high-temperature shockwaves to synthesize and stabilize single atoms at very high temperatures (1,500-2,000 K), achieved by a periodic on-off heating that features a short on state (55 ms) and a ten-times longer off state. The high temperature provides the activation energy for atom dispersion by forming thermodynamically favourable metal-defect bonds and the off-state critically ensures the overall stability, especially for the substrate. The resultant high-temperature single atoms exhibit a superior thermal stability as durable catalysts. The reported shockwave method is facile, ultrafast and universal (for example, Pt, Ru and Co single atoms, and carbon, CN and TiO substrates), which opens a general route for single-atom manufacturing that is conventionally challenging.
单原子催化剂的稳定性对其实际应用至关重要。尽管高温可以促进金属原子与基底之间形成键,从而提高稳定性,但它常常会导致原子团聚,并且与许多对温度敏感的基底不相容。在此,我们报告了利用可控高温冲击波在非常高的温度(1500 - 2000 K)下合成并稳定单原子,这是通过一种周期性通断加热实现的,其特点是导通状态短(55毫秒),关断状态长十倍。高温通过形成热力学上有利的金属 - 缺陷键为原子分散提供活化能,而关断状态则关键地确保了整体稳定性,特别是对于基底。由此产生的高温单原子作为耐用催化剂表现出卓越的热稳定性。所报道的冲击波方法简便、超快且通用(例如,铂、钌和钴单原子,以及碳、碳氮化物和二氧化钛基底),这为传统上具有挑战性的单原子制造开辟了一条通用途径。