Gas sensor and method of optimizing an array of gas sensors

Patent metadata

Field	Value
Publication number	US-11513100-B2
Application number	US-201816479675-A
Country	US
Kind code	B2
Filing date	Jan 26, 2018
Priority date	Jan 27, 2017
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

A gas sensor ( 100,200 ) includes at least one sensor device including a surface acoustic wave (SAW) device ( 110 ) or a quartz crystal microbalance (QCM) device ( 210 ), and a layer of metal organic framework (MOF) material ( 120,220 ) disposed on each of the at least one sensor device. The at least one sensor device is structured to sense a change in mass of the MOF material.

First claim

What is claimed is:

1. A gas sensor comprising:
at least one sensor device including a surface acoustic wave (SAW) device; and
a layer of metal organic framework (MOF) material disposed on each of the at least one sensor device,
wherein the at least one sensor device is structured to sense a change in mass of the MOF material,
wherein the at least one sensor device is a plurality of sensor devices arranged in an array, and
wherein the plurality of sensor devices includes a first sensor device having a first layer of MOF material disposed thereon and a second sensor device having a second layer of MOF material disposed thereon, wherein the first MOF material and the second MOF material are different.

2. The gas sensor of claim 1 , wherein the metal organic framework includes at least one of IRMOF-1, HKUST-1, NU-125, UiO-66, and ZIF-8.

3. The gas sensor of claim 1 , wherein the sensor device includes the SAW device, and wherein the layer of MOF material has a thickness within a range of about 100-300 nm.

4. The gas sensor of claim 1 , wherein the sensor device incudes the QCM device ( 210 ), and wherein the layer of MOF material ( 220 ) has a thickness within a range of about 100-300 nm.

5. The gas sensor of claim 1 , wherein the first layer of MOF material is composed of HKUST-1 and the second layer of MOF material is composed of UiO-66, and wherein the plurality of sensor devices includes a third sensor device having a third layer of material composed of ZIF-8.

6. The gas sensor of claim 1 , wherein the first layer of MOF material is composed of IRMOF-1, the second layer of MOF material is composed of HKUST-1, and wherein the plurality of sensor devices includes a third sensor device having a third layer of MOF material composed of UiO-66, a fourth sensor device having a fourth layer of MOF material composed of ZIF-8, and a fifth sensor device having a fifth layer of MOF material composed on MgMOF-74.

7. A method of optimizing an array of gas sensors each including a sensor device having a layer of MOF material disposed thereon, wherein the sensor device is structured to sense a change in mass of the MOF material, the method comprising:
selecting a plurality of gas mixtures;
selecting a plurality of MOF materials;
selecting a plurality of array sizes, the array size being the number of gas sensors in the array;
generating a set of potential arrays from the plurality of MOF materials and the plurality of array sizes, wherein each of the gas sensors in a selected potential array includes a different type of MOF material;
simulating adsorption characteristics of each of the MOF materials for each of the gas mixtures;
calculating an effectiveness score for each of the potential arrays; and
selecting one or more of the potential arrays based on the calculated effectiveness scores.

8. The method of claim 7 , wherein calculating the effectiveness score for each of the potential arrays comprises:
calculating a sensor array gas space (SAGS) score Φ for each of the potential arrays based on the following equation:

ϕ
W

=

Σ
⁢

⁢

S
ij

W

where W is a total number of combinations of pairs of gas mixtures selected from the plurality of gas mixtures and where S ij is a pairwise array score based on the following equation:

S
ij

=

m
ij

d
ij

where d ij is the Euclidean distance between two different gas mixtures, i and j, selected from the plurality of gas mixtures, each with N component gases, specified by their mole fraction, x k , based on the following equation:

d
ij

=

∑

k
=
1

N

⁢

⁢

(

x

k
,
i

-

x

k
,
j

)

2

and m ij is the Euclidean distance between mass changes in an M element MOF array adsorbing either gas mixture i or gas mixture j based on the following equation:
m ij =√{square root over (Σ k=1 M ( m k,i −m k,j ) 2 )}

9. The method of claim 8 , further comprising:
using the SAGS score as the effectiveness score;
selecting the potential array with the highest effectiveness score; and
fabricating the selected potential array.

10. The method of claim 7 , wherein the plurality of gas mixtures are selected by selecting a plurality of gas components and varying each of the gas components in concentrations from 0-1 mole fractions in a predetermined step size to generate the plurality of gas mixtures, and
wherein calculating the effectiveness score for each of the potential arrays comprises:
selecting a subset of the plurality of gas mixtures;
simulating adsorption characteristics of each of the MOF materials for each gas mixture in the subset of the plurality of gas mixtures;
for each of the MOF materials and each of the subset of the plurality of gas mixtures, calculating a probability distribution of the gas mixture from the subset of the plurality of gas mixtures being selected gas mixtures from the plurality of gas mixtures;
for each of the potential arrays, combining the probability distributions for each of the MOF materials in the potential array; and
calculating a Kullback-Liebler divergence (KLD) for each gas mixtures in the subset of the plurality of gas mixtures for each of the potential arrays using the following equation:

KLD
=

∑
i
N

⁢

P
i

⁢

⁢
log
⁢

Assignees

• Univ Pittsburgh Commonwealth Sys Higher Education
• Us Energy

Inventors

• Wilmer Christopher E
• Gustafson Jenna
• Ohodnicki Paul R
• Devkota Jagannath

Classifications

• G01N2291/0256

  Adsorption, desorption, surface mass change, e.g. on biosensors · CPC title

• G01N2291/0423

  Surface waves, e.g. Rayleigh waves, Love waves · CPC title

• G01N2291/106

  one or more transducer arrays · CPC title

• B01J20/226

  Coordination polymers, e.g. metal-organic frameworks [MOF], zeolitic imidazolate frameworks [ZIF] (preparation of metal complexes containing carboxylic acid moieties C07C51/418; MOF's per se C07F) · CPC title

• G01N29/022 Primary

  Fluid sensors based on microsensors, e.g. quartz crystal-microbalance [QCM], surface acoustic wave [SAW] devices, tuning forks, cantilevers, flexural plate wave [FPW] devices (microdevices per se B81B) · CPC title