Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals
Transport of hydrogen isotopes through interlayer spacing in van der Waals crystals
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DOI：
10.1038/s41565-018-0088-0
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发表时间：
2018-06-01
影响因子：
38.3
通讯作者：
Lozada-Hidalgo, M.
中科院分区：
文献类型：
--
作者：
Hu, S.;Gopinadhan, K.;Lozada-Hidalgo, M.
如果原子被限制在与其德布罗意波长相称的空间中，那么原子开始表现为波而不是经典粒子。在室温下，即使对于最轻的原子氢原子，这个长度也只有大约1埃。这将原子物种的量子限制现象限制在非常低的温度(1-5)范围内。在这里，我们展示了层状晶体原子平面之间的范德华间隙提供了埃大小的通道，使得质子的量子限制即使在室温下也是显而易见的。我们的输运测量表明，当热质子进入六方氮化硼和二硫化钼的范德华能隙时，热质子的势垒要比氚高得多。这归因于同位素的德布罗意波长的不同。一旦进入晶体，这两种同位素的传输都可以用经典扩散来描述，尽管其传输速度出人意料地快于水中的质子。展示的埃大小的通道可以用于原子量子限制的进一步研究，如果这项技术可以扩大规模，还可以用于筛选氢同位素。
Atoms start behaving as waves rather than classical particles if confined in spaces commensurate with their de Broglie wavelength. At room temperature this length is only about one angstrom even for the lightest atom, hydrogen. This restricts quantum-confinement phenomena for atomic species to the realm of very low temperatures(1-5). Here, we show that van der Waals gaps between atomic planes of layered crystals provide angstrom-size channels that make quantum confinement of protons apparent even at room temperature. Our transport measurements show that thermal protons experience a notably higher barrier than deuterons when entering van der Waals gaps in hexagonal boron nitride and molybdenum disulfide. This is attributed to the difference in the de Broglie wavelengths of the isotopes. Once inside the crystals, transport of both isotopes can be described by classical diffusion, albeit with unexpectedly fast rates comparable to that of protons in water. The demonstrated angstrom-size channels can be exploited for further studies of atomistic quantum confinement and, if the technology can be scaled up, for sieving hydrogen isotopes.