Chen I-Wen Peter, Tseng Yi-Lun, Huang Jeremiah Hao Ran, Chen Kuan-Lun, Liu Tsai Yun, Lee Jui-Chin
Department of Chemistry, National Cheng Kung University, Tainan 701, Taiwan.
Department of Applied Sciences, National Taitung University, Taitung 950, Taiwan.
J Phys Chem Lett. 2024 Feb 29;15(8):2287-2292. doi: 10.1021/acs.jpclett.3c03305. Epub 2024 Feb 22.
Enhancing electrocatalytic performance relies on effective phase control, which influences key catalytic properties, such as chemical stability and electrical conductivity. Traditional methods for manipulating the phase of transition-metal dichalcogenides (TMDs), including high-temperature synthesis, Li intercalation, and doping, involve harsh conditions and energy-intensive processes. This study introduces an innovative approach to crafting heterophase structures (2H-1T-WS) in TMDs, using WS as a model compound, encompassing both semiconducting (2H) and metallic (1T) types through a straightforward potential activation method. Insights from in situ electrochemical Raman spectroscopy, HR-TEM, and XPS measurements reveal distinctive partial phase-transition behavior. This behavior enables the partially exposed basal plane of 2H-1T-WS to demonstrate superior activity in the hydrogen evolution reaction (HER), attributed to enhanced electrical conductivity and the exposure of highly active sites. The potential-induced phase transition presents promising avenues for the development of catalysts with heterophase structures.
提高电催化性能依赖于有效的相控制，这会影响关键的催化性能，如化学稳定性和电导率。传统的用于操纵过渡金属二硫属化物（TMDs）相的方法，包括高温合成、锂嵌入和掺杂，都涉及苛刻的条件和能源密集型过程。本研究引入了一种创新方法，以WS作为模型化合物，通过简单的电位活化方法在TMDs中构建异相结构（2H-1T-WS），该结构包含半导体（2H）和金属（1T）两种类型。原位电化学拉曼光谱、高分辨透射电子显微镜（HR-TEM）和X射线光电子能谱（XPS）测量的结果揭示了独特的部分相变行为。这种行为使2H-1T-WS的部分暴露基面在析氢反应（HER）中表现出卓越的活性，这归因于电导率的提高和高活性位点的暴露。电位诱导相变为具有异相结构的催化剂的开发提供了有前景的途径。
