Abstract:
This paper focuses on high-entropy spinels, which represent a rapidly growing group of materials with physicochemical properties that make them suitable for hydrogen energy applications. The influence of high-pressure pure hydrogen on the chemical stability of three high-entropy oxide (HEO) sinter samples with a spinel structure was investigated. Multicomponent HEO samples were obtained via mechanochemical synthesis (MS) combined with high-temperature thermal treatment. Performing the free sintering procedure on powders after MS at 1000 °C for 3 h in air enabled achieving single-phase (Cr0.2Fe0.2Mg0.2Mn0.2Ni0.2)3O4 and (Cu0.2Fe0.2Mg0.2Ni0.2Ti0.2)3O4 powders with a spinel structure, and in the case of (Cu0.2Fe0.2Mg0.2Ti0.2Zn0.2)3O4, a spinel phase in the amount of 95 wt.% was achieved. A decrease in spinel phase crystallite size and an increase in lattice strains were established in the synthesized spinel powders. The hydrogenation of the synthesized samples in a high-pressure hydrogen atmosphere was investigated using Sievert\'s technique. The results of XRD, SEM, and EDS investigations clearly showed that pure hydrogen at temperatures of up to 250 °C and a pressure of up to 40 bar did not significantly impact the structure and microstructure of the (Cr0.2Fe0.2Mg0.2Mn0.2Ni0.2)3O4 ceramic, which demonstrates its potential for application in hydrogen technologies.
摘要:
本文主要研究高熵尖晶石,它们代表了一组快速增长的材料,这些材料具有使其适合氢能应用的物理化学性质。研究了高压纯氢对三种具有尖晶石结构的高熵氧化物(HEO)烧结样品的化学稳定性的影响。通过机械化学合成(MS)结合高温热处理获得多组分HEO样品。在空气中在1000°C下对MS后的粉末进行3小时的自由烧结程序,可以获得具有尖晶石结构的单相(Cr0.2Fe0.2Mg0.2Mn0.2Ni0.2)3O4和(Cu0.2Fe0.2Mg0.2Ni0.2Ti0.2)3O4粉末,在(Cu0.2Fe0.2Mg0.2Ti0.2Zn0.2)3O4的情况下,尖晶石相的含量为95wt。%已实现。在合成的尖晶石粉末中建立了尖晶石相微晶尺寸的减小和晶格应变的增加。使用Sievert技术研究了合成样品在高压氢气气氛中的氢化作用。XRD的结果,SEM,和EDS研究清楚地表明,在高达250°C的温度和高达40bar的压力下,纯氢不会显着影响(Cr0.2Fe0.2Mg0.2Mn0.2Ni0.2)3O4陶瓷的结构和微观结构,这证明了其在氢技术中的应用潜力。