Semimetal compound of Pt and method for making the same

Patent metadata

Field	Value
Publication number	US-10407799-B2
Application number	US-201715642406-A
Country	US
Kind code	B2
Filing date	Jul 6, 2017
Priority date	Sep 28, 2016
Publication date	Sep 10, 2019
Grant date	Sep 10, 2019

Abstract

The disclosure relates to a semimetal compound of Pt and a method for making the same. The semimetal compound is a single crystal material of PtSe2. The method comprises: providing a PtSe2 polycrystalline material; placing the PtSe2 polycrystalline material in a reacting chamber; placing chemical transport medium in the reacting chamber; evacuating the reacting chamber to be vacuum less than 10 Pa; placing the reacting chamber at a temperature gradient, wherein the reacting chamber has a first end at a temperature of 1200 degrees Celsius to 1000 degrees Celsius and a second end opposite to the first end and at a temperature of 1000 degrees Celsius to 900 degrees Celsius; and keeping the reacting chamber in the temperature gradient for 10 days to 30 days.

First claim

What is claimed is:

1. A method for making semimetal compound of Pt, the method comprising:
Placing both a PtSe 2 polycrystalline material and a chemical transport medium in a first end of a reacting chamber, wherein the chemical transport medium is selected from the group consisting of SeBr 4 , I 2 , Br 2 , Cl 2 and SeCl 4 ;
evacuating the reacting chamber to be vacuum with a pressure lower than 10 Pa; creating a temperature gradient inside the reacting chamber from approximately 1200 to 1000 degrees Celsius at the first end to approximately 1000 to 900 degrees Celsius at a second end of the reacting chamber, the second end being opposite to the first end; and
maintaining the temperature gradient for 10 days to 30 days to obtain a reaction product comprising a single crystal PtSe 2 semimetal compound at the second end of the reacting chamber, wherein the PtSe 2 polycrystalline material reacts with the chemical transport medium to form a Pt-L (g) compound and a Se x (g) element at the first end of the reacting chamber and the Pt-L (g) compound reacts with the Se x (g) element to form the single crystal PtSe 2 semimetal compound and the chemical transport medium at the second end of the reacting chamber, wherein L represents an element of the chemical transport medium that is different from the element Se.

2. The method of claim 1 , wherein a concentration of the chemical transport medium is in a range of about 5 mg/mL to about 20 mg/mL.

3. The method of claim 1 , wherein the pressure is lower than 1 Pa.

4. The method of claim 1 , wherein the first end of the reacting chamber is sealed, the second end is an open end, and the reacting chamber is a quartz tube.

5. The method of claim 4 , wherein the evacuating the reacting chamber further comprises sealing the open end by fast heating.

6. The method of claim 4 , wherein the method of maintaining the temperature gradient comprising horizontally placing the quartz tube in a tubular furnace.

7. The method of claim 1 , further comprising washing the reaction product to obtain a pure single crystal PtSe 2 semimetal compound.

8. The method of claim 7 , wherein the reaction product is washed by alcohol.

9. The method of claim 1 , wherein the reaction product comprises a type-II Dirac single crystal PtSe 2 semimetal compound.

10. The method of claim 1 , wherein the reaction product comprises a single crystal PtSe 2 semimetal compound having a tilted Dirac cone.

11. The method of claim 1 , wherein the reaction product comprises a single crystal PtSe 2 semimetal compound exhibiting anomalous negative magnetoresistance.

Assignees

• Univ Tsinghua
• Hon Hai Prec Ind Co Ltd

Inventors

• Zhang Ke-Nan
• Yan Ming-Zhe
• Zhou shu-yun
• Wu Yang
• Fan Shou-Shan

Classifications

• C30B29/46 Primary

  Sulfur-, selenium- or tellurium-containing compounds · CPC title

• C01B19/007

  Tellurides or selenides of metals (C01B19/002 takes precedence) · CPC title

• C30B25/00

  Single-crystal growth by chemical reaction of reactive gases, e.g. chemical vapour-deposition growth · CPC title

• C30B25/02

  Epitaxial-layer growth · CPC title

• C01P2006/42

  Magnetic properties · CPC title