JoVE - Journal of Visualized Experiments
JoVE Visualize
Contact Us
このページは機械翻訳されています。他のページは英語で表示される場合があります。 View in English

炭酸硫化水素における室温超伝導性

  • 0Department of Mechanical Engineering, School of Engineering and Applied Sciences, University of Rochester, Rochester, NY, USA.
Nature +

|

2020年10月15日

|

2020年10月15日

PubMedで要約を見る

まとめ

この要約は機械生成です。

研究者は新しい炭酸硫化水素系で室温の超伝導性を達成した. この突破は 低圧で動作する超伝導体を 開発する可能性を秘めています

科学分野

  • 凝縮物質物理学
  • 材料科学
  • 高圧物理学

背景

  • 室温の超伝導性を観測することは,実験物理学の重要な課題です.
  • 最近の進歩は,極端な圧力下での水素に富んだ材料の高温超伝導性を含む.
  • 硫化水素 (H2S) の超伝導性は,H3Sに203Kと155GPaで変換され,重要な発見となりました.

研究 の 目的

  • 超伝導性を達成するための炭酸硫化水素システムの可能性を調査する.
  • 超伝導材料の水素に富んだ前駆体へのメタンの導入の影響を調査する.
  • 高圧下での新型超伝導物質の合成と特徴付け

主な方法

  • 元素前駆物質を炭酸硫黄化物に光化学的に変換する.
  • ダイヤモンド・アンビル・セル (最大275GPa) を使用して高圧を施す.
  • 超伝導性の特徴は,ゼロ抵抗,磁気感受性,および外部磁場への反応 (9 Tまで) を測定する.
  • ラーマン光譜は,金属化前の化学的および構造的変換を検知するために使用されました.

主要な成果

  • 超伝導性は,最大移行温度287. 7 ± 1.2 K (約15°C) の炭酸硫化水素系で267 ± 10 GPaで観察されました.
  • 超伝導状態は広範囲の圧力 (140275 GPa) にわたって持続し,220 GPa以上で顕著に増加した.
  • 超伝導性の証拠には,ゼロの電気抵抗,二磁気信号,および外部磁場による移行温度抑制が含まれています.
  • 推定上臨界磁場は,Ginzburg-Landauモデルを使用して約62Tと決定された.

結論

  • この研究は,新しい光化学合成炭酸硫黄水素で室温の超伝導性を示した.
  • この三元システム内の化学的チューニングは,低圧で超伝導性を達成するための有望な道を示しています.
  • これらの水素に富んだ材料に関するさらなる研究は,高温超伝導体の実用的な応用への道を開くことができるでしょう.

関連する概念動画

Superconductor 01:24

1.6K

A substance that reaches superconductivity, a state in which magnetic fields cannot penetrate, and there is no electrical resistance, is referred to as a superconductor. In 1911, Heike Kamerlingh Onnes of Leiden University, a Dutch physicist, observed a relation between the temperature and the resistance of the element mercury. The mercury sample was then cooled in liquid helium to study the linear dependence of resistance on temperature. It was observed that, as the temperature decreased, the...

Types Of Superconductors 01:28

1.5K

A superconductor is a substance that offers zero resistance to the electric current when it drops below a critical temperature. Zero resistance is not the only interesting phenomenon as materials reach their transition temperatures. A second effect is the exclusion of magnetic fields. This is known as the Meissner effect. A light, permanent magnet placed over a superconducting sample will levitate in a stable position above the superconductor. High-speed trains that levitate on strong...

Supercritical Fluid Chromatography 01:18

635

Supercritical fluid chromatography (SFC) provides a beneficial substitute for gas chromatography (GC) and liquid chromatography (LC) for certain samples because it merges the top attributes of both techniques. SFC allows the separation and analysis of compounds that GC or LC does not easily manage. These compounds are traditionally nonvolatile or thermally unstable, making GC unsuitable and lacking functional groups required for HPLC analysis.
SFC utilizes a supercritical fluid mobile phase,...

Preparation and Reactions of Sulfides 02:26

5.5K

Sulfides are the sulfur analog of ethers, just as thiols are the sulfur analog of alcohol. Like ethers, sulfides also consist of two hydrocarbon groups bonded to the central sulfur atom. Depending upon the type of groups present, sulfides can be symmetrical or asymmetrical. Symmetrical sulfides can be prepared via an SN2 reaction between 2 equivalents of an alkyl halide and one equivalent of sodium sulfide.

Asymmetrical sulfides can be synthesized by treating thiols with an alkyl halide and a...

Chirality at Nitrogen, Phosphorus, and Sulfur 02:30

6.6K

Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...

Preparation and Reactions of Thiols 02:33

7.2K

Thiols are prepared using the hydrosulfide anion as a nucleophile in a nucleophilic substitution reaction with alkyl halides. For instance, bromobutane reacts with sodium hydrosulfide to give butanethiol.

This reaction fails because the thiol product can undergo a second nucleophilic substitution reaction in the presence of an excess alkyl halide to generate a sulfide as a by-product.

This limitation can be overcome by using thiourea as the nucleophile. The reaction first produces an alkyl...