Condensation on Superhydrophobic Copper Oxide Nanostructures
Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]...
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| Format: | Article |
| Language: | en_US |
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ASME International
2014
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| Online Access: | http://hdl.handle.net/1721.1/84987 https://orcid.org/0000-0001-7045-1200 |
| _version_ | 1811079185322475520 |
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| author | Enright, Ryan Miljkovic, Nenad Nam, Youngsuk Wang, Evelyn N. Dou, Nicholas G. |
| author2 | Massachusetts Institute of Technology. Department of Mechanical Engineering |
| author_facet | Massachusetts Institute of Technology. Department of Mechanical Engineering Enright, Ryan Miljkovic, Nenad Nam, Youngsuk Wang, Evelyn N. Dou, Nicholas G. |
| author_sort | Enright, Ryan |
| collection | MIT |
| description | Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]. In this work, we investigated a scalable synthesis technique to produce oxide nanostructures on copper surfaces capable of sustaining superhydrophobic condensation and characterized the growth and departure behavior of condensed droplets. Nanostructured copper oxide (CuO) films were formed via chemical oxidation in an alkaline solution. A dense array of sharp CuO nanostructures with characteristic heights and widths of ~1 μm and ~300 nm, respectively, were formed. A gold film was deposited on the surface and functionalized with a self-assembled monolayer to make the surfaces hydrophobic. Condensation on these surfaces was then characterized using optical microscopy (OM) and environmental scanning electron microscopy (ESEM) to quantify the distribution of nucleation sites and elucidate the growth behavior of individual droplets with a characteristic size of ∼1 to 10 μm at low supersaturations. Comparison of the observed behavior to a recently developed model for condensation on superhydrophobic surfaces [2, 3] suggests a restricted regime of heat transfer enhancement compared to a corresponding smooth hydrophobic surface due to the large apparent contact angles demonstrated by the CuO surface. |
| first_indexed | 2024-09-23T11:11:13Z |
| format | Article |
| id | mit-1721.1/84987 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T11:11:13Z |
| publishDate | 2014 |
| publisher | ASME International |
| record_format | dspace |
| spelling | mit-1721.1/849872022-10-01T01:52:58Z Condensation on Superhydrophobic Copper Oxide Nanostructures Enright, Ryan Miljkovic, Nenad Nam, Youngsuk Wang, Evelyn N. Dou, Nicholas G. Massachusetts Institute of Technology. Department of Mechanical Engineering Miljkovic, Nenad Enright, Ryan Miljkovic, Nenad Nam, Youngsuk Wang, Evelyn N. Dou, Nicholas G. Condensation is an important process in both emerging and traditional power generation and water desalination technologies. Superhydrophobic nanostructures promise enhanced condensation heat transfer by reducing the characteristic size of departing droplets via a surface-tension-driven mechanism [1]. In this work, we investigated a scalable synthesis technique to produce oxide nanostructures on copper surfaces capable of sustaining superhydrophobic condensation and characterized the growth and departure behavior of condensed droplets. Nanostructured copper oxide (CuO) films were formed via chemical oxidation in an alkaline solution. A dense array of sharp CuO nanostructures with characteristic heights and widths of ~1 μm and ~300 nm, respectively, were formed. A gold film was deposited on the surface and functionalized with a self-assembled monolayer to make the surfaces hydrophobic. Condensation on these surfaces was then characterized using optical microscopy (OM) and environmental scanning electron microscopy (ESEM) to quantify the distribution of nucleation sites and elucidate the growth behavior of individual droplets with a characteristic size of ∼1 to 10 μm at low supersaturations. Comparison of the observed behavior to a recently developed model for condensation on superhydrophobic surfaces [2, 3] suggests a restricted regime of heat transfer enhancement compared to a corresponding smooth hydrophobic surface due to the large apparent contact angles demonstrated by the CuO surface. Massachusetts Institute of Technology. Undergraduate Research Opportunities Program United States. Dept. of Energy. Office of Science (Solid-State Solar-Thermal Energy Conversion Center) United States. Air Force Office of Scientific Research. Young Investigator Program National Science Foundation (U.S.) (Award ECS-0335765) 2014-02-18T19:48:19Z 2014-02-18T19:48:19Z 2012-03 Article http://purl.org/eprint/type/ConferencePaper 978-0-7918-5477-8 http://hdl.handle.net/1721.1/84987 Enright, Ryan, Nicholas Dou, Nenad Miljkovic, Youngsuk Nam, and Evelyn N. Wang. “Condensation on Superhydrophobic Copper Oxide Nanostructures.” In ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer, 419. ASME International, 2012. https://orcid.org/0000-0001-7045-1200 en_US http://dx.doi.org/10.1115/MNHMT2012-75277 Proceedings of the ASME 2012 Third International Conference on Micro/Nanoscale Heat and Mass Transfer Creative Commons Attribution-Noncommercial-Share Alike http://creativecommons.org/licenses/by-nc-sa/4.0/ application/pdf ASME International Nenad Miljkovic |
| spellingShingle | Enright, Ryan Miljkovic, Nenad Nam, Youngsuk Wang, Evelyn N. Dou, Nicholas G. Condensation on Superhydrophobic Copper Oxide Nanostructures |
| title | Condensation on Superhydrophobic Copper Oxide Nanostructures |
| title_full | Condensation on Superhydrophobic Copper Oxide Nanostructures |
| title_fullStr | Condensation on Superhydrophobic Copper Oxide Nanostructures |
| title_full_unstemmed | Condensation on Superhydrophobic Copper Oxide Nanostructures |
| title_short | Condensation on Superhydrophobic Copper Oxide Nanostructures |
| title_sort | condensation on superhydrophobic copper oxide nanostructures |
| url | http://hdl.handle.net/1721.1/84987 https://orcid.org/0000-0001-7045-1200 |
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