Змочування та контактна взаємодія ZnO з розплавами системи Ag-Ge

• Дата: 2025
• Автори: Дуров, O. В., Євтушенко, A. I., Коваль, O. Ю., Стецюк, T. В., Полуянська, В. В., Шаповал, І. В.
• Формат: Стаття
• Мова: Англійська
• Опубліковано: Chuiko Institute of Surface Chemistry National Academy of Sciences of Ukraine 2025
• Теми: оксид цинку; металевий розплав; змочування; поверхня розділу; контактна взаємодія
• Онлайн доступ: https://surfacezbir.com.ua/index.php/surface/article/view/807
• Назва журналу: Surface

The aim of the work was to investigate wetting and contact interactions in pairs containing ZnO and Ag-Ge system melts on a macro scale. Sintered ZnO-ceramics without dopands of 15% porosity was used. Ag-Ge alloys were prepared by remelting. Wetting was studied by the sessile drop method. Wetting experiments were carried out at 1000°C in vacuum at germanium concentrations of 0, 1, 2, 3, 5, 10 and 100 at. %. The samples were photographed and the images obtained were processed using Adobe Photoshop. Sem investigations were carried out on the cross-sections of solidified on the ZnO surface metal drops using the Axia from Thermoscientific microscope with an energy-dispersive analyzer. Based on the data obtained, a graph of the dependence of wetting on the concentration of germanium was constructed. The addition of Ge to the Ag melt significantly improves its wetting of ZnO substrate (at 0 at. %. Ge q=136°, at 2 at. % Ge q=62, at 10 at. % Ge q=41° and pure Ge spreads fully). There were dissolution of the substrate in the melt and diffusion of melt components into ZnO substrate. Both Ge and Ag diffusion in the depth of the substrate were observed. For drops of 1 and 2 at. % Ge, the concentration of Ge in ZnO substrate after the experiment was higher than in the drops. These phenomena are explained by the oxidation of Ge when reacting with ZnO. Oxygen in the composition of metal melts in contact with solid oxides is an adhesive-active component, as it forms complexes with metals that are adsorbed on interfaces, reducing intersurface tension, and thus improving wetting. In this case, oxygen-germanium complexes are formed and increase adhesion, then adsorbed Ge diffuses in ZnO. Diffusion of Ag is provided by formation of Zn vacancies in ZnO structure due to presence of Ge4+. This effect can be used to increase the adhesion of metals to ZnO. At the same time, the interaction is very intense, this must be taken into account when developing devices containing tight contacts of the ZnO with metals. It is worth considering the possibility of using other elements that intensively interact with ZnO (Sn, In, Ga) as adhesive-active additives to inert metals (Ag, Au).