在氧化物中通过氧化状态控制对硫化物进行新化合物和阶段选择
Xiuquan Zhou1, David J Mandia1, Hyowon Park2
1Materials Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States.
Journal of the American Chemical Society
|August 19, 2021
概括
混合氧化物作为强大的溶剂,用于发现新的硫化物材料. 这种方法精确地控制
科学领域:
- 材料科学
- 固态化学
- 无机化学
背景情况:
- 盐对新材料的发现具有前景,但对氧化状态的控制有限.
- 水溶液能更好地控制氧化状态,但对某些材料的合成效果较差.
研究的目的:
- 证明混合氧化物可以作为材料合成的调节流.
- 为了实现对氧化状态的精确控制,用于生长三元化物单晶.
- 探索新的三元和二元硫化物相及其特性.
主要方法:
- 使用混合/KOH流的三元K-Ni-S化合物的合成.
- 新硫化物材料的晶体生长和相位识别.
- 使用X射线吸收光谱 (XAS),X射线光电子光谱 (XPS) 和密度函数理论 (DFT) 的计算进行了表征.
主要成果:
- 在LiOH/KOH溶液中实现了精确的Ni氧化状态控制,使所有已知的三元K-Ni-S化合物的生长成为可能.
- 发现了几种新阶段,包括β-K2Ni3S4,低价值KNi4S2和K4Ni9S11的新多型.
- 一个新的分层二进制Ni2S通过从KNi4S2中对K的拓性脱合成,呈现出适用于间化学的范德瓦尔斯间隙.
结论:
- 混合氧化物是控制三元素的合成和晶体生长的有效流体.
- 这项研究成功地获得了具有独特结构和电子特性的新型低价值硫化物 (KNi4S2和Ni2S).
- 新发现的Ni2S作为一个有前途的宿主材料.
相关概念视频
Preparation and Reactions of Sulfides
5.2K
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.
5.2K
Precipitation Gravimetry
8.8K
Precipitation gravimetry is based on converting an analyte into a sparingly soluble precipitate, which is separated by filtration and weighed. An ideal precipitate should be pure, insoluble, of known composition, and easily filtered from the reaction mixture.
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
In determining nickel by gravimetric analysis, a precipitant of ethanolic dimethylglyoxime is added to a hot nickel salt solution. This is quickly followed by the dropwise addition of dilute ammonia solution until precipitation occurs. A...
8.8K
Electrodeposition
809
Electrodeposition is a technique used to separate an analyte from interferents by electrochemical processes. Here, the analyte is a metal ion that can be deposited on an electrode immersed in the sample solution. The electrochemical setup consists of an anode and a cathode. When an electric current is applied to the setup, oxidation occurs at the anode. At the cathode, which consists of a large metal surface, metal ions undergo reduction and deposit onto the surface.
Electrodeposition can...
Electrodeposition can...
809
Precipitation and Co-precipitation
2.9K
Precipitation and coprecipitation methods can be used to separate a mixture of ions in a solution. In qualitative inorganic analysis, ions that form sparingly soluble precipitates with the same reagent are separated based on the differences in solubility products. For example, consider the separation of Cu(II) and Fe(II) ions by precipitation as insoluble sulfides. First, copper(II) sulfide is precipitated by the addition of acidic H2S, where the dissociation of H2S is suppressed. Adding H2S...
2.9K
Extraction: Advanced Methods
631
Metal ions can be separated from one another by complexation with organic ligands–the chelating agent– to form uncharged chelates. Here, the chelating agent must contain hydrophobic groups and behave as a weak acid, losing a proton to bind with the metal. Since most organic ligands used in this process are insoluble or undergo oxidation in the aqueous phase, the chelating agent is initially added to the organic phase and extracted into the aqueous phase. The metal-ligand complex is...
631
Formation of Complex Ions
24.6K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
24.6K


