酸素発生反応におけるCoOナノ粒子の電気触媒活性に及ぼす大きさと形状の影響

Effect of the Size and Shape on the Electrocatalytic Activity of CoO Nanoparticles in the Oxygen Evolution Reaction.

• S Saddeler
• U Hagemann
• S Schulz

抄録

CoOナノ粒子は、異なる溶媒中でアセチルアセトナート(Co(acac))または硝酸コバルト(II)硝酸コバルト(NO)を熱分解し、大気中で焼成することにより、大きさと形状を選択的に合成した。その結果、球状,立方体,八面体,板状のナノ粒子を高収率で形成することができた。得られたナノ粒子は、X線回折,走査透過電子顕微鏡,エネルギー分散型X線分析,X線光電子分光法によって特徴づけられた。また、ナノ粒子の大きさや形状が酸素発生反応における電極触媒活性に与える影響についても明らかにした。

CoO nanoparticles were size- and shape-selectively synthesized in a solvothermal approach by the thermal decomposition of either cobalt(II) acetylacetonate [Co(acac)] or cobalt(II) nitrate [Co(NO)] in different solvents followed by calcination under air. Spherical, cubic, octahedral, and platelike nanoparticles with narrow size distributions and sizes ranging from 8 to 90 nm were formed in high yield. The nanoparticles were characterized by X-ray diffraction, scanning and transmission electron microscopy, energy-dispersive X-ray analysis, and X-ray photoelectron spectroscopy. The distinctive influence of the size and shape of the nanoparticles on the electrocatalytic activity in the oxygen evolution reaction is also demonstrated.