He Tianou, Wang Weicong, Shi Fenglei, Yang Xiaolong, Li Xiang, Wu Jianbo, Yin Yadong, Jin Mingshang
State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, China.
Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, China.
Nature. 2021 Oct;598(7879):76-81. doi: 10.1038/s41586-021-03870-z. Epub 2021 Oct 6.
Platinum (Pt) has found wide use as an electrocatalyst for sustainable energy conversion systems. The activity of Pt is controlled by its electronic structure (typically, the d-band centre), which depends sensitively on lattice strain. This dependence can be exploited for catalyst design, and the use of core-shell structures and elastic substrates has resulted in strain-engineered Pt catalysts with drastically improved electrocatalytic performances. However, it is challenging to map in detail the strain-activity correlations in Pt-catalysed conversions, which can involve a number of distinct processes, and to identify the optimal strain modification for specific reactions. Here we show that when ultrathin Pt shells are deposited on palladium-based nanocubes, expansion and shrinkage of the nanocubes through phosphorization and dephosphorization induces strain in the Pt(100) lattice that can be adjusted from -5.1 per cent to 5.9 per cent. We use this strain control to tune the electrocatalytic activity of the Pt shells over a wide range, finding that the strain-activity correlation for the methanol oxidation reaction and hydrogen evolution reaction follows an M-shaped curve and a volcano-shaped curve, respectively. We anticipate that our approach can be used to screen out lattice strain that will optimize the performance of Pt catalysts-and potentially other metal catalysts-for a wide range of reactions.
铂（Pt）作为可持续能源转换系统的电催化剂已得到广泛应用。Pt的活性由其电子结构（通常是d带中心）控制，而电子结构又对晶格应变敏感依赖。这种依赖性可用于催化剂设计，核壳结构和弹性基底的使用已产生了应变工程化的Pt催化剂，其电催化性能得到了大幅改善。然而，详细描绘Pt催化转化过程中的应变-活性相关性具有挑战性，因为这可能涉及许多不同的过程，而且要确定特定反应的最佳应变修饰也很困难。在此，我们表明，当超薄Pt壳层沉积在钯基纳米立方体上时，纳米立方体通过磷化和脱磷的膨胀和收缩会在Pt(100)晶格中诱导应变，该应变可在-5.1%至5.9%之间调节。我们利用这种应变控制在很宽的范围内调节Pt壳层的电催化活性，发现甲醇氧化反应和析氢反应的应变-活性相关性分别遵循M形曲线和火山形曲线。我们预计，我们的方法可用于筛选出能优化Pt催化剂以及潜在的其他金属催化剂在广泛反应中性能的晶格应变。
