Hubkowska Katarzyna, Pająk Małgorzata, Czerwiński Andrzej
Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw, Poland.
Materials (Basel). 2023 Jun 24;16(13):4556. doi: 10.3390/ma16134556.
Thin layers (up to 1 µm) of Pd-Ir alloys were electrodeposited from aqueous, galvanic baths of PdCl and IrCl mixtures. The morphology of the electrodeposits was examined by means of scanning electron microscopy. The composition of alloys was determined with the use of energy-dispersive spectroscopy, atomic absorption spectrometry, X-ray photoelectron spectroscopy, and Auger electron spectroscopy. For the studies of the electrochemical properties of alloys, cyclic voltammetry, chronoamperometry, and chronopotentiometry were used. It was found that Pd-Ir alloy electrodes were surface-enriched with Pd. Pd-Ir alloys subjected to different electrochemical treatment involving hydrogen sorption changed their surface state. The continuous hydrogen sorption enhanced the Ir ions' dissolution. The values of thermodynamic functions of hydrogen sorption in strong alkaline electrolytes were comparable with those in acidic electrolytes, whereas the kinetics of the process in alkaline medium was hindered. The miscibility gap in the Pd-Ir-H system vanished for the electrode containing ca. 93.7 at.% Pd.
从氯化钯（PdCl）和氯化铱（IrCl）混合物的水相原电池镀液中电沉积出了厚度达1微米的钯铱合金薄层。通过扫描电子显微镜对电沉积物的形态进行了检查。利用能量色散光谱、原子吸收光谱、X射线光电子能谱和俄歇电子能谱测定了合金的成分。为了研究合金的电化学性质，采用了循环伏安法、计时电流法和计时电位法。发现钯铱合金电极表面富含钯。经过涉及氢吸附的不同电化学处理的钯铱合金改变了它们的表面状态。持续的氢吸附增强了铱离子的溶解。在强碱性电解质中氢吸附的热力学函数值与酸性电解质中的相当，而该过程在碱性介质中的动力学受到阻碍。对于含约93.7原子百分比钯的电极，钯 - 铱 - 氢体系中的混溶间隙消失。
