Condensation on Superhydrophobic Surfaces: The Role of Local Energy Barriers and Structure Length Scale
- 27 September 2012
- journal article
- research article
- Published by American Chemical Society (ACS) in Langmuir
- Vol. 28 (40), 14424-14432
- https://doi.org/10.1021/la302599n
Abstract
Water condensation on surfaces is a ubiquitous phase-change process that plays a crucial role in nature and across a range of industrial applications, including energy production, desalination, and environmental control. Nanotechnology has created opportunities to manipulate this process through the precise control of surface structure and chemistry, thus enabling the biomimicry of natural surfaces, such as the leaves of certain plant species, to realize superhydrophobic condensation. However, this “bottom-up” wetting process is inadequately described using typical global thermodynamic analyses and remains poorly understood. In this work, we elucidate, through imaging experiments on surfaces with structure length scales ranging from 100 nm to 10 μm and wetting physics, how local energy barriers are essential to understand non-equilibrium condensed droplet morphologies and demonstrate that overcoming these barriers via nucleation-mediated droplet–droplet interactions leads to the emergence of wetting states not predicted by scale-invariant global thermodynamic analysis. This mechanistic understanding offers insight into the role of surface-structure length scale, provides a quantitative basis for designing surfaces optimized for condensation in engineered systems, and promises insight into ice formation on surfaces that initiates with the condensation of subcooled water.United States. Dept. of Energy. Office of Basic Energy Sciences (Solid-State Solar-Thermal Energy Conversion Center)National Science Foundation (U.S.) (Award ECS-0335765Keywords
This publication has 39 references indexed in Scilit:
- Effect of Droplet Morphology on Growth Dynamics and Heat Transfer during Condensation on Superhydrophobic Nanostructured SurfacesACS Nano, 2012
- Methodology for Imaging Nano-to-Microscale Water Condensation Dynamics on Complex NanostructuresACS Nano, 2011
- Three dimensional aspects of droplet coalescence during dropwise condensation on superhydrophobic surfacesSoft Matter, 2011
- Self-Propelled Dropwise Condensate on Superhydrophobic SurfacesPhysical Review Letters, 2009
- Urbanisation and its impact on building energy consumption and efficiency in ChinaRenewable Energy, 2009
- Advances in seawater desalination technologiesDesalination, 2008
- A review on buildings energy consumption informationEnergy and Buildings, 2008
- High efficiency electric power generation: The environmental roleProgress in Energy and Combustion Science, 2007
- Dropwise condensation on superhydrophobic surfaces with two-tier roughnessApplied Physics Letters, 2007
- Air-side performance of brazed aluminum heat exchangers under dehumidifying conditionsInternational Journal of Refrigeration, 2002