Visualization of Diffusion within Nanoarrays
The direct experimental characterization of diffusion processes at nanoscale remains a challenge that could help elucidate processes in biology, medicine and technology. In this report, two experimental approaches were employed to visualize ion diffusion profiles at the orifices of nanopores (radius...
| Main Authors: | , , , , , , , , , |
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| Format: | Journal Article |
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American Chemical Society
2016
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| Online Access: | http://purl.org/au-research/grants/arc/DP130102040 http://hdl.handle.net/20.500.11937/38612 |
| _version_ | 1848755367494811648 |
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| author | Liu, Yang Holzinger, A. Knittel, P. Poltorak, L. Gamero-Quijano, A. Rickard, William Walcarius, A. Herzog, G. Kranz, C. Arrigan, Damien |
| author_facet | Liu, Yang Holzinger, A. Knittel, P. Poltorak, L. Gamero-Quijano, A. Rickard, William Walcarius, A. Herzog, G. Kranz, C. Arrigan, Damien |
| author_sort | Liu, Yang |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | The direct experimental characterization of diffusion processes at nanoscale remains a challenge that could help elucidate processes in biology, medicine and technology. In this report, two experimental approaches were employed to visualize ion diffusion profiles at the orifices of nanopores (radius (ra) of 86 ± 6 nm) in array format: (1) electrochemically assisted formation of silica deposits based on surfactant ion transfer across nanointerfaces between two immiscible electrolyte solutions (nanoITIES); (2) combined atomic force - scanning electrochemical microscopy (AFM-SECM) imaging of topography and redox species diffusion through the nanopores. The nature of the diffusion zones formed around the pores is directly related to the interpore distance within the array. Nanopore arrays with different ratios of pore center-to-center separation (rc) to pore radius (ra) were fabricated by focused ion beam (FIB) milling of silicon nitride (SiN) membranes, with 100 pores in a hexagonal arrangement. The ion diffusion profiles determined by the two visualization methods indicated the formation of overlapped or independent diffusion profiles at nanopore arrays with rc/ra ratios of 21 ± 2 and 91 ± 7, respectively. In particular, the silica deposition method resulted in formation of a single deposit encompassing the complete array with closer nanopore arrangement, whereas individual silica deposits were formed around each nanopore within the more widely spaced array. The methods reveal direct experimental evidence of diffusion zones at nanopore arrays and provide practical illustration that the pore-pore separation within such arrays has a significant impact on diffusional transport as the pore size is reduced to the nanoscale. These approaches to nanoscale diffusion zone visualization open up possibilities for better understanding of molecular transport processes within miniaturized systems. |
| first_indexed | 2025-11-14T08:55:11Z |
| format | Journal Article |
| id | curtin-20.500.11937-38612 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:55:11Z |
| publishDate | 2016 |
| publisher | American Chemical Society |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-386122017-09-13T15:45:38Z Visualization of Diffusion within Nanoarrays Liu, Yang Holzinger, A. Knittel, P. Poltorak, L. Gamero-Quijano, A. Rickard, William Walcarius, A. Herzog, G. Kranz, C. Arrigan, Damien The direct experimental characterization of diffusion processes at nanoscale remains a challenge that could help elucidate processes in biology, medicine and technology. In this report, two experimental approaches were employed to visualize ion diffusion profiles at the orifices of nanopores (radius (ra) of 86 ± 6 nm) in array format: (1) electrochemically assisted formation of silica deposits based on surfactant ion transfer across nanointerfaces between two immiscible electrolyte solutions (nanoITIES); (2) combined atomic force - scanning electrochemical microscopy (AFM-SECM) imaging of topography and redox species diffusion through the nanopores. The nature of the diffusion zones formed around the pores is directly related to the interpore distance within the array. Nanopore arrays with different ratios of pore center-to-center separation (rc) to pore radius (ra) were fabricated by focused ion beam (FIB) milling of silicon nitride (SiN) membranes, with 100 pores in a hexagonal arrangement. The ion diffusion profiles determined by the two visualization methods indicated the formation of overlapped or independent diffusion profiles at nanopore arrays with rc/ra ratios of 21 ± 2 and 91 ± 7, respectively. In particular, the silica deposition method resulted in formation of a single deposit encompassing the complete array with closer nanopore arrangement, whereas individual silica deposits were formed around each nanopore within the more widely spaced array. The methods reveal direct experimental evidence of diffusion zones at nanopore arrays and provide practical illustration that the pore-pore separation within such arrays has a significant impact on diffusional transport as the pore size is reduced to the nanoscale. These approaches to nanoscale diffusion zone visualization open up possibilities for better understanding of molecular transport processes within miniaturized systems. 2016 Journal Article http://hdl.handle.net/20.500.11937/38612 10.1021/acs.analchem.6b00513 http://purl.org/au-research/grants/arc/DP130102040 American Chemical Society fulltext |
| spellingShingle | Liu, Yang Holzinger, A. Knittel, P. Poltorak, L. Gamero-Quijano, A. Rickard, William Walcarius, A. Herzog, G. Kranz, C. Arrigan, Damien Visualization of Diffusion within Nanoarrays |
| title | Visualization of Diffusion within Nanoarrays |
| title_full | Visualization of Diffusion within Nanoarrays |
| title_fullStr | Visualization of Diffusion within Nanoarrays |
| title_full_unstemmed | Visualization of Diffusion within Nanoarrays |
| title_short | Visualization of Diffusion within Nanoarrays |
| title_sort | visualization of diffusion within nanoarrays |
| url | http://purl.org/au-research/grants/arc/DP130102040 http://hdl.handle.net/20.500.11937/38612 |