In the present research, self-supported hierarchical nanocomposites of Ni₃Se₂/Ni(OH)₂/Ni and Ni₃Se₂/Ni were developed and their performance as a hydrogen evolution reaction (HER) catalyst for alkaline electrolytic water splitting was demonstrated. The composite Ni₃Se₂/Ni(OH)₂/Ni was obtained through a hydrothermal process and subsequent selenization reaction by heat treatment, while the Ni₃Se₂/Ni was synthesized only through a selenization reaction by heat treatment. The materials were characterized by confocal microscopy, transmission electron microscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and Raman spectroscopy. The results that displayed different structures were grown on the Ni-foam, such as Ni(OH)₂ nanoleaflets, Ni₃Se₂ nanosticks composed of spheres, and Ni₃Se₂ nanowires between Ni(OH)₂ nanoleaflets, for Ni(OH)₂/Ni, Ni₃Se₂/Ni, and Ni₃Se₂/Ni(OH)₂/Ni composites, respectively. The catalysts exhibited an excellent hydrogen evolution reaction activity with overpotentials of 170.0 and 194.8 mV at a current density of 10 mA cm⁻², with a Tafel slope of 123.5 and 127.3 mV decade⁻¹ for Ni₃Se₂/Ni and Ni₃Se₂/Ni(OH)₂/Ni, respectively.

Graphical abstract

在本研究中，开发了自支撑的Ni ₃ Se ₂ / Ni（OH）₂ / Ni和Ni ₃ Se ₂ / Ni分层纳米复合材料，它们作为碱性电解水分解的放氢反应（HER）催化剂的性能为演示。通过水热处理和随后的热处理通过硒化反应获得Ni ₃ Se ₂ / Ni（OH）₂ / Ni复合材料，而Ni ₃ Se ₂/ Ni仅通过热处理的硒化反应合成。通过共聚焦显微镜，透射电子显微镜，扫描电子显微镜，能量色散X射线光谱，X射线衍射和拉曼光谱对材料进行表征。所显示不同的结构的结果是生长在镍泡沫材料，例如Ni（OH）_2个nanoleaflets，镍₃硒_2个nanosticks球体组成，和Ni ₃硒_2层的Ni之间的纳米线（OH）_2个nanoleaflets，对于镍（OH ）₂ / Ni，Ni ₃ Se ₂ / Ni和Ni ₃ Se ₂ / Ni（OH）₂/ Ni复合材料。催化剂表现出优异的氢释放反应活性，在10 mA cm ^-2的电流密度下的超电势为170.0和194.8 mV，对于Ni ₃ Se ₂ / Ni和Ni ₃ Se的Tafel斜率为123.5和127.3 mV October ^-1。₂ / Ni（OH）₂ / Ni。

图形概要