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Bubbles play a ubiquitous role in electrochemical gas evolution reactions. However, a mechanistic understanding of how bubbles affect the energy efficiency of electrochemical processes remains limited to date, impeding effective approaches to further boost the performance of gas evolution systems. From a perspective of the analogy between heat and mass transfer, bubbles in electrochemical gas evolution reactions exhibit highly similar dynamic behaviors to them in the liquid–vapor phase change. Recent developments of liquid–vapor phase change systems have substantially advanced the fundamental knowledge of bubbles, leading to unprecedented enhancement of heat transfer performance. In this Review, we aim to elucidate a promising opportunity of understanding bubble dynamics in electrochemical gas evolution reactions through a lens of phase change heat transfer. We first provide a background about key parallels between electrochemical gas evolution reactions and phase change heat transfer. Then, we discuss bubble dynamics in gas evolution systems across multiple length scales, with an emphasis on exciting research problems inspired by new insights gained from liquid–vapor phase change systems. Lastly, we review advances in engineered surfaces for manipulating bubbles to enhance heat and mass transfer, providing an outlook on the design of high-performance gas evolving electrodes.
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A nanofluidics study on nanoscale gas bubble defects in dispensing-based nanoimprint lithography
Detrimental nanoscale gas bubble defects seriously hinder the practical applications of nanoimprint lithography in manufacturing of nanoelectronic devices. Here, we present a nanofluidics study on the formation and evolution mechanisms of nanoscale bubble defects in dispensing-based UV-curable nanoimprint lithography processes. Our work indicates that the formation of nanoscale bubble defects is mainly attributed to the pinning of resist spreading edges at the nanostructures or contaminants on the mold/substrate surfaces. Such pinning-induced nanoscale gas bubbles undergo an evolution process governed by the combinational effect of surface pinning and gas dissolution into resist. Such an evolution process results in a prominent drop of the gas pressure inside bubbles and therefore prevents nanoscale gas bubble defects from the complete dissolution into resists. This work identifies the critical mechanisms responsible for the formation of detrimental nanoscale bubble defects and provides important insights for the ultimate elimination of such defects
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- Award ID(s):
- 1636132
- PAR ID:
- 10063724
- Date Published:
- Journal Name:
- Proceedings of the 17th IEEE International Conference on Nanotechnolog
- Page Range / eLocation ID:
- 788 to 791
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/NANO.2017.8117426
