In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni)
Aqueous phase pH is a critical metric with significant importance in understanding reactive transport processes in porous media. At the microscale, however, traditional pH detection methods face challenges in capturing dynamic pH due to limited sample volume and sensing time. To overcome these limit...
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| Format: | Article |
| Language: | English |
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MDPI AG
2024-01-01
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| Series: | Colloids and Interfaces |
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| Online Access: | https://www.mdpi.com/2504-5377/8/1/9 |
| _version_ | 1797298554086096896 |
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| author | Ge Zhang Negar Nazari Anthony R. Kovscek |
| author_facet | Ge Zhang Negar Nazari Anthony R. Kovscek |
| author_sort | Ge Zhang |
| collection | DOAJ |
| description | Aqueous phase pH is a critical metric with significant importance in understanding reactive transport processes in porous media. At the microscale, however, traditional pH detection methods face challenges in capturing dynamic pH due to limited sample volume and sensing time. To overcome these limitations, we leveraged micro/nanofabrication techniques to create a microfluidic porous medium coated with polyaniline (PAni) on its surface. Using this innovative microfluidic design, we achieved colorimetric delineation of pH spatial distribution with fast response and robustness in porous media. By conducting coinjection tests with hydrochloric acid (pH = 2) and DI water (pH ≈ 5.8, equilibrated with air) at various flow rates and relative flow rate ratios in a sandstone-patterned microfluidic device, we observed dynamic pH changes in porous media and obtained a comprehensive understanding of the acid advection-diffusion dynamics. The results highlighted the capability of PAni to enable microscale pH sensing. This research contributes to the development of advanced porous media microfluidics and applications, particularly in mass transfer limits during reactive transport of carbon dioxide sequestration and geological hydrogen storage. |
| first_indexed | 2024-03-07T22:36:36Z |
| format | Article |
| id | doaj.art-7a509b36cb734498a03bc82923946044 |
| institution | Directory Open Access Journal |
| issn | 2504-5377 |
| language | English |
| last_indexed | 2024-03-07T22:36:36Z |
| publishDate | 2024-01-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Colloids and Interfaces |
| spelling | doaj.art-7a509b36cb734498a03bc829239460442024-02-23T15:12:49ZengMDPI AGColloids and Interfaces2504-53772024-01-0181910.3390/colloids8010009In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni)Ge Zhang0Negar Nazari1Anthony R. Kovscek2Department of Energy Science and Engineering, Stanford University, 367 Panama St., Stanford, CA 94305, USADepartment of Energy Science and Engineering, Stanford University, 367 Panama St., Stanford, CA 94305, USADepartment of Energy Science and Engineering, Stanford University, 367 Panama St., Stanford, CA 94305, USAAqueous phase pH is a critical metric with significant importance in understanding reactive transport processes in porous media. At the microscale, however, traditional pH detection methods face challenges in capturing dynamic pH due to limited sample volume and sensing time. To overcome these limitations, we leveraged micro/nanofabrication techniques to create a microfluidic porous medium coated with polyaniline (PAni) on its surface. Using this innovative microfluidic design, we achieved colorimetric delineation of pH spatial distribution with fast response and robustness in porous media. By conducting coinjection tests with hydrochloric acid (pH = 2) and DI water (pH ≈ 5.8, equilibrated with air) at various flow rates and relative flow rate ratios in a sandstone-patterned microfluidic device, we observed dynamic pH changes in porous media and obtained a comprehensive understanding of the acid advection-diffusion dynamics. The results highlighted the capability of PAni to enable microscale pH sensing. This research contributes to the development of advanced porous media microfluidics and applications, particularly in mass transfer limits during reactive transport of carbon dioxide sequestration and geological hydrogen storage.https://www.mdpi.com/2504-5377/8/1/9microfluidicspH indicationporous mediapolyanilinereactive transport |
| spellingShingle | Ge Zhang Negar Nazari Anthony R. Kovscek In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni) Colloids and Interfaces microfluidics pH indication porous media polyaniline reactive transport |
| title | In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni) |
| title_full | In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni) |
| title_fullStr | In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni) |
| title_full_unstemmed | In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni) |
| title_short | In Situ pH Measurement in Microfluidic Porous Media Indicated by Surfaces Functionalized with Polyaniline (PAni) |
| title_sort | in situ ph measurement in microfluidic porous media indicated by surfaces functionalized with polyaniline pani |
| topic | microfluidics pH indication porous media polyaniline reactive transport |
| url | https://www.mdpi.com/2504-5377/8/1/9 |
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