Electrostatic charging of jumping droplets

Miljkovic, Nenad; Preston, Daniel J.; Enright, Ryan; Wang, Evelyn N.

doi:10.1038/ncomms3517

Cited by 223 publications

(226 citation statements)

References 59 publications

Supporting

Mentioning

222

Contrasting

Unclassified

Order By: Relevance

“…Recently, Miljkovic et al [109] reported that microdrops (with diameters of ≈10 µm) self-jumping off CMDSP surfaces can carry a positive electrostatic charge due to the electric-doublelayer charge separation at the interface of the microdrops and a hydrophobic film. Subsequently, they took advantage of this unique droplet-charging ability to demonstrate electrostatic energy harvesting.…”

Section: Electrostatic Energy Harvestingmentioning

confidence: 99%

Recent Progress in Bionic Condensate Microdrop Self‐Propelling Surfaces

2017

View full text Add to dashboard Cite

interest has focused on utilizing the lowadhesivity nature of superhydrophobic surfaces for the rapid removal of condensate microdrops, as this has significance in fundamental research and technological innovation. Example applications are the enhancement of condensation heat transfer for high-efficiency thermal management and energy utilization, [20][21][22][23][24][25] energy-effective antifreezing for airconditioner heat exchangers and aircraft wings, [26][27][28] and electrostatic energy harvesting. [29] In general, condensate drops on typical flat hydrophobic surfaces are only shed off under gravity when their sizes are comparable to the capillary length (≈2.7 mm for water), [30] which creates undesirable effects such as large thermal resistance [20][21][22][23][24][25] and the freezing of subcooled drops. [26][27][28] Clearly, a great challenge is the timely removal of condensate drops at the microscale where the gravitational effect does not work. The latest research has indicated that these small-scale condensate microdrops may self-remove via mutual coalescence as long as the coalescence-released excess surface energy is larger than the interface adhesion-induced energy dissipation. [31] Much effort has been devoted to exploring the utilization of knowledge of bionic low-adhesivity superhydrophobicity to develop innovative condensate microdrop self-propelling (CMDSP) surfaces. Different from traditional superhydrophobic surfaces, which are characterized by the bouncing or rolling off of deposited millimeter-size large drops, [32,33] CMDSP surfaces support the self-removal capability of smallscale condensate microdrops. It has been reported that classical superhydrophobic lotus leaves (Figure 1a), [34][35][36][37] as well as artificial surfaces consisting of hierarchical micro-and nanostructures, [38] one-tier microstructures, [39][40][41][42][43] or nanostructures [44,45] with larger characteristic interspaces, present a low-adhesivity property to the deposited water macrodrops, but become highly adhesive to condensed microdrops (Figure 1b). This is because moisture easily penetrates the microscale valleys or cavities. Clearly, superhydrophobic surfaces with irrationally designed surface structures can enhance the solid-liquid interfacial adhesion instead of promoting the rapid removal of condensed drops. Accordingly, it is still a challenge to design and fabricate very effective low-adhesivity superhydrophobic surfaces with the self-removal ability of condensate microdrops. Recently, there has been a large breakthrough in understanding the mechanism and construction rules of bionic CMDSP surfaces, leading to the exploration of fabrication methods for the surface functionalization of widely used metal materials and the Bionic condensate microdrop self-propelling (CMDSP) surfaces are attracting increased attention as novel, low-adhesivity superhydrophobic surfaces due to their value in fundamental research and technological innovation, e.g., for enhancing heat transfer, energy-effective antifreezing, and...

show abstract

Section: Electrostatic Energy Harvestingmentioning

confidence: 99%

Recent Progress in Bionic Condensate Microdrop Self‐Propelling Surfaces

2017

View full text Add to dashboard Cite

show abstract

“…Also, in the case of white cement, can be bolded regarding to Dives in Misericordia Church in Rome (Liu et al, 2014b) and for Roof can be pointed to Cricket Stadium in Dubai Sports City (Murakami et al, 2014). There is a research that shows that by covering with active concrete 15% of ceilings in city of Milan, the pollution would be decreased up to 50% (Miljkovic et al, 2013;Zhang et al, 2015b). Another company named Heidelberg Cement has produced TioCemTM, which is another air pollution reducer in case of self-cleaning cement (Hancock et al, 2012;Vorobyev and Guo, 2015;Long et al, 2015).…”

Section: Commercial Applicationsmentioning

confidence: 99%

Recent Progress in Self-Cleaning Materials with Different Suitable Applications

Chermahini¹,

Ostad‐Ali‐Askari²,

Eslamian³

et al. 2018

American Journal of Engineering and Applied Sciences

View full text Add to dashboard Cite

Self-cleaning properties have received significant attention for the importance of their potential. Coatings at Nano-scales offer possibilities of using materials for self-cleaning surfaces. Recent efforts have begun to focus on the kinds of materials including metals, semiconductors and polymers. Such materials can have enormous potential in only a few applications. Moreover, the production of these materials requires high costs with low photo activity. In this regard, TiO 2 and its derived materials have shown acceptable and effective suggestions for this application. Moreover, the mechanism of self-cleaning has been explained by the effect of hydrophilic and hydrophobic. Hydrophilic and hydrophobic can have many applications in different areas like water purification, microfluidics and photovoltaic. In this review, the application of self-cleaning in solar cells and environment as well as TiO 2 derived materials and their applications in water management have been briefly illustrated. In addition, it has been explained that a huge number of self-cleaning materials, applications and improvement in utilities have been essential. In short, we have conducted a comprehensive review of the new approach and to mention numerous materials with hydrophobic and hydrophilic properties would be promising for most environmental concerns. Bio-inspired surface respond in nature through hydrophobic (Cicada Wing, Butterfly Wing, Lotus Leaf, Rice Leaf) and hydrophilic (Fish Scale, Snail Shell, Shark Skin) properties was divided in 4 and 3 respectively. Anti reflective coatings with self-cleaning properties have drowned considerable attention for both their basic appearances and vast applied usages. Antireflective coatings with self-cleaning properties have been considered because of their fascinating features and vast diversity of empirical uses.

show abstract

“…While this droplet jumping phenomenon has been studied on a range of surfaces, past work has neglected electrostatic interactions and assumed charge neutrality of the droplets. We show that jumping droplets on a variety of superhydrophobic surfaces, including copper oxide, zinc oxide, and silicon nanopillars, gain a net positive charge that causes them to repel each other mid-flight [7]. The charge is determined experimentally by observing droplet motion in a uniform electric field.…”

Section: Jumping-droplet-enhanced Condensationmentioning

confidence: 99%

Nanoengineered Surfaces for Thermal Energy Conversion

Bhatia

Preston

Bierman

et al. 2015

J. Phys.: Conf. Ser.

Self Cite

View full text Add to dashboard Cite

Abstract.We provide an overview of the impact of using nanostructured surfaces to improve the performance of solar thermophotovoltaic (STPV) energy conversion and condensation systems. We demonstrated STPV system efficiencies of up to 3.2%, compared to ≤1% reported in the literature, made possible by nanophotonic engineering of the absorber and emitter. For condensation systems, we showed enhanced performance by using scalable superhydrophobic nanostructures via jumping-droplet condensation. Furthermore, we observed that these jumping droplets carry a residual charge which causes the droplets to repel each other mid-flight. Based on this finding of droplet residual charge, we demonstrated electric-field-enhanced condensation and jumping-droplet electrostatic energy harvesting.

show abstract

Electrostatic charging of jumping droplets

Cited by 223 publications

References 59 publications

Recent Progress in Bionic Condensate Microdrop Self‐Propelling Surfaces

Recent Progress in Bionic Condensate Microdrop Self‐Propelling Surfaces

Recent Progress in Self-Cleaning Materials with Different Suitable Applications

Nanoengineered Surfaces for Thermal Energy Conversion

Contact Info

Product

Resources

About