2h to 1t phase based transition metal dichalcogenide sensor for optical and electronic detection of strong electron donor chemical vapors

Patent metadata

Field	Value
Publication number	US-2018024085-A1
Application number	US-201715652491-A
Country	US
Kind code	A1
Filing date	Jul 18, 2017
Priority date	Jul 19, 2016
Publication date	Jan 25, 2018
Grant date	—

Abstract

Optical and electronic detection of chemicals, and particularly strong electron-donors, by 2H to 1T phase-based transition metal dichalcogenide (TMD) films, detection apparatus incorporating the TMD films, methods for forming the detection apparatus, and detection systems and methods based on the TMD films are provided. The detection apparatus includes a 2H phase TMD film that transitions to the 1T phase under exposure to strong electron donors. After exposure, the phase state can be determined to assess whether all or a portion of the TMD has undergone a transition from the 2H phase to the 1T phase. Following detection, TMD films in the 1T phase can be converted back to the 2H phase, resulting in a reusable chemical sensor that is selective for strong electron donors.

First claim

What is claimed:

1 . A method for detecting whether an unknown chemical vapor comprises a strong electron donor, comprising:
providing at least one sensor comprising a transition metal chalcogenide thin film comprising at least one region having a 2H phase; exposing the at least one sensor to an unknown chemical vapor; evaluating the transition metal chalcogenide thin film comprising at least one region having a 2H phase to determine whether the phase of the at least one region is 2H or 1T; and detecting that the unknown chemical vapor comprises a strong electron donor if the phase of the at least one region of the transition metal chalcogenide thin film has changed from 2H to 1T.

2 . The method of claim 1 , wherein the transition metal chalcogenide thin film is evaluated using Raman spectroscopy, photoluminescence spectroscopy, or electronic resistance measurement.

3 . The method of claim 1 , further comprising annealing the at least one region of the transition metal chalcogenide thin film after the phase has changed from 2H to 1T, thereby returning the at least one region of the transition metal chalcogenide thin film to the 2H phase.

4 . The method of claim 3 , wherein the annealing is carried out by a heating element provided in the sensor, a handheld heater, or an oven.

5 . The method of claim 1 , wherein the strong electron donor is selected from the group consisting of TEA (triethylamine), TPA (tripropylamine), BuAm (butylamine), ammonia, arsines, acetone, acetonitrile, pyridine, DMMP (dimethyl methylphosphonate), TATP (triacetone triperoxide), DMSO (dimethylsulfoxide), VE (O-ethyl-S-[2-(diethylamino)ethyl]ethylphosphonothioate), VG (O,O-diethyl-S-[2-(diethylamino)ethyl]phosphorothioate), VM (O-ethyl-S-[2-(diethylamino)ethyl]methylphosphonothioate), VX (O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothioate), TNT (2-methyl-1,3,5-trinitrobenzene), TEX (4,10-dinitro-2,6, 8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.0 5,9 .0 3,11 ]-dodecane), HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), CL-20 (2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 3, 11 .0 5,9 ]dodecane), and RDX (1,3,5-trinitro-1,3,5-triazinane).

6 . The method of claim 1 , further comprising transmitting a signal indicating that a strong electron donor is detected.

7 . A system for detecting whether a chemical vapor comprises a strong electron donor, comprising:
at least one sensor comprising a transition metal chalcogenide thin film comprising at least one region having a 2H phase; an apparatus for evaluating the transition metal chalcogenide thin film comprising at least one region having a 2H phase to assess whether the phase of the at least one region is 2H or 1T; and a transmitter that generates a signal indicating that the chemical vapor comprises a strong electron donor if the phase of the at least one region of the transition metal chalcogenide thin film has changed from 2H to 1T.

8 . The system of claim 7 , wherein the apparatus for evaluating the transition metal chalcogenide thin film is a Raman spectrometer, photoluminescence spectrometer, or electronic resistance sensor.

9 . The system of claim 7 , further comprising a heating element for annealing the at least one region of the transition metal chalcogenide thin film after the phase has changed from 2H to 1T, thereby returning the at least one region of the transition metal chalcogenide thin film to the 2H phase.

10 . The system of claim 9 , wherein the heating element is provided in the sensor.

11 . The system of claim 9 , wherein the heating element is a handheld heater or an oven.

12 . The system of claim 7 , wherein the strong electron donor is selected from the group consisting of TEA (triethylamine), TPA (tripropylamine), BuAm (butylamine), ammonia, arsines, acetone, acetonitrile, pyridine, DMSO (dimethylsulfoxide), DMMP (dimethyl methylphosphonate), TATP (triacetone triperoxide), VE (O-ethyl-S-[2-(diethylamino)ethyl]ethylphosphonothioate), VG (O,O-diethyl-S-[2-(diethylamino)ethyl]phosphorothioate), VM (O-ethyl-S-[2-(diethylamino)ethyl]methylphosphonothioate), VX (O-ethyl S-(2-diisopropylaminoethyl) methylphosphonothioate), TNT (2-methyl-1,3,5-trinitrobenzene), TEX (4,10-dinitro-2,6, 8,12-tetraoxa-4,10-diazatetracyclo[5.5.0.0 5,9 . 0 3,11 ]-dodecane), HMX (octahydro- 1 , 3 , 5 , 7 -tetranitro- 1 , 3 , 5 , 7 -tetrazocine), CL-20 (2,4,6,8,10,12-Hexanitro-2,4,6,8,10,12-hexaazatetracyclo[ 5 . 5 . 0 . 0 3,11 .0 5,9 ]dodecane), and RDX (1,3,5-trinitro-1,3,5-triazinane).

13 . A sensor for detecting strong electron donors, comprising:
a substrate; a transition metal dichalcogenide thin film comprising at least one first region having a 2H phase; and at least two electrically-conductive leads, wherein at least two second regions of the transition metal dichalcogenide thin film that are directly in contact with the at least two electrically-conductive leads have a 1T phase.

14 . The sensor of claim 13 , further comprising a power source.

15 . The sensor of claim 13 , wherein the power source is selected from the group consisting of electrochemical cells, solar cells, fuel cells, and capacitors.

16 . The sensor of claim 13 , wherein the substrate comprises a material selected from the group consisting of silicon, silicon dioxide, aluminum oxide, sapphire, germanium, gallium arsenide, alloys of silicon and germanium, indium phosphide, polypropylene, polyethylene, polyethylene naphthalate, polyether ether ketone, polycarbonate, polyethersulfone, polyimide, and combinations thereof.

17 . The sensor of claim 13 , wherein the transition metal dichalcogenide thin film is selected from the group consisting of MoS 2 , MoSe 2 , WS 2 , WSe 2 , NbS 2 , NbSe 2 , TaS 2 , and TaSe 2 .

18 . The sensor of claim 13 , wherein the at least two electrically-conductive leads comprise materials selected from the group consisting of gold, titanium, chromium, platinum, palladium, copper, silver, aluminum, and alloys and combinations thereof.

19 . The sensor of claim 13 , further comprising an electromagnetic signal transmitter.

20 . The sensor of claim 19 , wherein the electromagnetic signal transmitter is a radio transmitter.

Assignees

• Us Gov Sec Navy

Inventors

• Friedman Adam L
• Perkins F Keith
• Culbertson James C
• Hanbicki Aubrey T
• Campbell Paul M

Classifications

• G01N27/26 Primary

  by investigating electrochemical variables; by using electrolysis or electrophoresis · CPC title

• C07C211/05

  Mono-, di- or tri-ethylamine · CPC title

• C01G35/00

  Compounds of tantalum · CPC title

• C01B19/04 Primary

  Binary compounds {including binary selenium-tellurium compounds (C01B19/004, C01B19/005, C01B19/007 take precedence)} · CPC title

• C07C211/07

  containing one, two or three alkyl groups, each having the same number of carbon atoms in excess of three · CPC title