Giziński Damian, Brudzisz Anna, Lee Jinhee, Harishchandre Ruturaj, Choi Jinsub, Stȩpniowski Wojciech J, Ziegler Kirk J
Faculty of Advanced Technologies and Chemistry, Military University of Technology, 00908 Warsaw, Poland.
Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, 43007 Tarragona, Spain.
Inorg Chem. 2025 Apr 21;64(15):7437-7449. doi: 10.1021/acs.inorgchem.5c00068. Epub 2025 Apr 9.
The morphological evolution of copper oxide surfaces during anodization was investigated using scanning electron microscopy (SEM), chronoamperometry, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The addition of ethylenediaminetetraacetic acid (EDTA) as a Cu chelating agent near the anode slows key mechanistic steps, providing insight into the factors driving the formation of crystalline Cu(OH) nanoneedles. The correlation of chronoamperometric data with SEM images revealed a four-stage process, beginning with the formation of an initial passive oxide layer, followed by nucleation. The comprehensive analysis of experimental results demonstrates that while electrochemical processes are necessary to initiate nanoneedle growth, the subsequent growth mechanism is not driven by direct electrochemical oxidation. Instead, supersaturation of the dissolved copper species near the electrode surface leads to nucleation and growth of Cu(OH) nanoneedles. The interaction with EDTA at different concentrations results in various morphologies of copper oxide surfaces, ranging from nanoneedles to disordered porous structures. This unique mechanism of copper oxide formation during anodization enables precise control of the surface properties, offering potential applications in catalysis and various energy technologies, including both production and storage.
利用扫描电子显微镜（SEM）、计时电流法、X射线衍射（XRD）和X射线光电子能谱（XPS）研究了阳极氧化过程中氧化铜表面的形态演变。在阳极附近添加乙二胺四乙酸（EDTA）作为铜螯合剂会减缓关键的机理步骤，从而深入了解驱动结晶Cu(OH)纳米针形成的因素。计时电流数据与SEM图像的相关性揭示了一个四阶段过程，首先是形成初始钝化氧化层，然后是成核。对实验结果的综合分析表明，虽然电化学过程是启动纳米针生长所必需的，但随后的生长机制并非由直接电化学氧化驱动。相反，电极表面附近溶解的铜物种的过饱和导致了Cu(OH)纳米针的成核和生长。与不同浓度的EDTA相互作用会导致氧化铜表面出现各种形态，从纳米针到无序多孔结构。这种阳极氧化过程中氧化铜形成的独特机制能够精确控制表面性质，在催化和包括生产与存储在内的各种能源技术中具有潜在应用。
