Bannenberg Lars J, Schreuders Herman, Kim Hyunjeong, Sakaki Kouji, Hayashi Shigenobu, Ikeda Kazutaka, Otomo Toshiya, Asano Kohta, Dam Bernard
Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft, The Netherlands.
Energy Process Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba West, 16-1 Onogawa, Tsukuba, Ibaraki 305-8569, Japan.
J Phys Chem Lett. 2021 Nov 18;12(45):10969-10974. doi: 10.1021/acs.jpclett.1c03411. Epub 2021 Nov 5.
Metal hydrides may play a paramount role in a future hydrogen economy. While most applications are based on nanostructured and confined materials, studies considering the structural response of these materials to hydrogen concentrate on bulk material. Here, using in- and out-of-plane X-ray diffraction and reflectometry, we study the fcc ↔ fct transition in Hf thin films, an optical hydrogen-sensing material. We show that the confinement of Hf affects this transition: compared to bulk Hf, the transition is pushed to a higher hydrogen-to-metal ratio, the tetragonality of the fct phase is reduced, and phase coexistence is suppressed. These nanoconfinement effects ensure the hysteresis-free response of hafnium to hydrogen, enabling its remarkable performance as a hydrogen-sensing material. In a wider perspective, the results highlight the profound influences of the nanostructuring and nanoconfinement of metal hydrides on their structural response to hydrogen with a significant impact on their applicability in future devices.
金属氢化物可能在未来的氢经济中发挥至关重要的作用。虽然大多数应用基于纳米结构和受限材料，但考虑这些材料对氢的结构响应的研究主要集中在块状材料上。在这里，我们使用面内和面外X射线衍射和反射测量技术，研究了光学氢传感材料Hf薄膜中的fcc ↔ fct转变。我们表明，Hf的受限会影响这种转变：与块状Hf相比，转变被推向更高的氢与金属比，fct相的四方度降低，并且相共存受到抑制。这些纳米限域效应确保了铪对氢的无滞后响应，使其作为氢传感材料具有卓越的性能。从更广泛的角度来看，这些结果突出了金属氢化物的纳米结构化和纳米限域对其氢结构响应的深远影响，对它们在未来器件中的适用性具有重大影响。
