Interface control and catalytic performances of Au-NiSx heterostructures
Interface control and catalytic performances of Au-NiSx heterostructures
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Au-NiS异质结构的界面控制和催化性能
DOI：
10.1016/j.cej.2019.122794
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发表时间：
2020
影响因子：
15.1
通讯作者：
Wang Rongming
中科院分区：
文献类型：
--
作者：
Lv Yuepeng;Duan Sibin;Zhu Yuchen;Guo Haizhong;Wang Rongming
硫化镍(NiSx)作为一种很有前途的析氢反应催化剂，引起了人们的极大兴趣。然而，已报道的NiSx的HER催化活性相对较低，因为它们的导电性较差。通过提高NiSx的电子电导率，有望进一步提高NiSx的HER催化性能。利用金属-半导体界面的协同效应，构建由贵金属和半导体组成的异质结是提高其物理化学性能的有效方法。在这里，我们用不同的溶剂热方法设计和合成了Au-NiSx异质结构，包括核@壳、蛋黄壳和低聚物类结构。对于金核周围有空隙的蛋黄壳结构，提出了一种包含Kirkendall效应的形成机制，而不是种子生长的核@壳结构。催化性能测试表明，由于Au和NiSx界面之间的电子转移，Au@NiSxcore@壳纳米粒子(NPs)的催化性能优于Au-NiSxolk壳结构、低聚物样结构和纯NiSxNPs。具有核@壳和蛋黄壳纳米结构的Au-NiSxNPs在10 mA/ 时的过电位分别为253 mV和263 mV，低于低聚物状Au-NiSx(283 mV)和纯NiSx(321 mV)。Au@NiSxcore@壳结构的塔菲尔斜率(43.7mV/dec)也是最低的。这些结果表明，核@壳纳米粒子具有最好的HER性能，其次是蛋黄壳纳米粒子和低聚物纳米粒子。这些发现证实了通过界面结构控制来调节电子转移可以有效地优化金属-半导体异质结的物理化学性能。
Nickel sulfides (NiSx) as promising catalysts for hydrogen evolution reaction (HER) have attracted much interest. However, the HER catalytic activities of NiSxreported are relatively low for their poor electrical conductivity. The HER catalytic performance of NiSxis expected to be further enhanced by increasing their electronic conductivity. Constructing heterostructures consisting of noble metal and semiconductor has been proven to be an efficient method to promote their physicochemical performances benefitting from synergistic effects along the metal-semiconductor interface. Here, Au-NiSxheterostructures including core@shell, yolk-shell, and oligomer-like structures have been designed and synthesized by different solvothermal methods. A formation mechanism involving the Kirkendall effect has been proposed for the yolk-shell structure with an empty space around the Au core rather than the seeded grown core@shell structure. Catalytic performance measurements indicate that the Au@NiSxcore@shell nanoparticles (NPs) exhibit superior HER catalytic property to Au-NiSxyolk-shell, oligomer-like structures, and “pure” NiSxNPs, resulting from the electron transfer between Au and NiSxinterfaces. The overpotentials of Au-NiSxNPs with core@shell and yolk-shell nanostructures are 253 mV and 263 mV at 10 mA/cm2, respectively, which are lower than those of oligomer-like Au-NiSx(283 mV) and pure NiSx(321 mV) NPs. The Tafel slope of Au@NiSxcore@shell structure (43.7 mV/dec) is also the lowest. These results demonstrate that the core@shell NPs possess the best HER performances, followed by their yolk-shell and oligomer-like counterparts. These findings confirm that the physicochemical performances of the metal-semiconductor heterostructures can be efficiently optimized by adjusting the electron transfer through the interface structure control.