• Applied Microscopy
• /
• 제46권4호
• /
• pp.201-205
• /
• 2016

Functional surfaces in nature have been continuously observed because of their ability to adapt to the environment. To this end, methods such as scanning electron microscopy (SEM) have been widely used, and their wetting functions have been characterized via environmental SEM. We investigated the superhydrophobic hairy leaves of Pelargonium tomentosum, i.e., peppermint-scented geranium. Their surface features and wettability were studied at multiple-scales, i.e., macro-, micro-, and sub-micro scales. The surfaces of the investigated leaves showed superhydrophobicity at the macro-, and micro-scales. The wetting or condensing behavior was studied for molecule-size water vapors, which easily adhered to the hairy surface owing to their significantly lower size in comparison to that of the surface.

• 공업화학
• /
• 제28권6호
• /
• pp.691-695
• /
• 2017

본 연구에서는 알카라인 연료전지 환원극 가스확산층에 내열화학성이 우수한 초발수 성능을 부여하기 위하여 PDMS 코팅 공정을 최적화하였다. 성격이 상이한 두 개의 상용 가스확산층을 선택하였으며, 소재의 열적 안정성을 검토하여 코팅 온도를 최적화하고, PDMS 점도를 제어하여 코팅 균일성을 확보하고자 하였다. PDMS 전구체의 점도와 관계없이 $200^{\circ}C$ 부근에서 코팅하게 되면 모든 확산층 표면에서 높은 초발수 성능을 나타내었다. 가혹실험 조건에서 초발수 성능변화를 측정한 결과 1000 CS PDMS를 이용하여 28BC 가스확산층에 코팅한 경우가 가장 높은 내구성을 나타내었다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2013년도 제44회 동계 정기학술대회 초록집
• /
• pp.97-97
• /
• 2013

The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on metals by both nano-flake or needle patterns and tuning of the surface energy. Metals including steel alloys and aluminum were provided with hierarchical micro/nanostructures of metaloxides induced by fluorination and a subsequent catalytic reaction of fluorine ions on metal surfaces in water with various ranges from room to boiling temperature of water. Then, a hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective regions surrounded by superhydrophobic surfaces. We show that wettability contrast surfaces align liquid water within patterned hydrophilic regions during the condensation process. Furthermore, this method could have a greater potential to align other liquids or living cells.

• 공업화학
• /
• 제30권2호
• /
• pp.141-144
• /
• 2019

물 재이용을 위한 오일 폐수 처리 기술은 일반적으로 물과 오일을 분리하고자 하는 유수분리장치를 이용하는데, 최근 다양한 표면 개질 방법을 이용하여 기능성이 향상된 유수분리막을 기반으로 유수분리장치를 구현하고자 하는 연구개발이 지속적으로 이어지고 있다. 분리막 소재 기술은 분리 선택성 및 내구성 등 성능뿐만 아니라 경제성 및 가공성등 상용화를 위한 적용성이 검토되어야 하며, 소재의 최적 성능을 최대한 발휘될 수 있도록 효과적인 장치가 구비되어야 한다. 본 논문에서는 분리막 소재의 상용 수준의 대면적 가공성 및 효과적인 유수분리 장치에 대해서 고찰하고자 한다.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2012년도 제43회 하계 정기 학술대회 초록집
• /
• pp.122-122
• /
• 2012

The exterior structures of natural organisms have continuously evolved by controlling wettability, such as the Namib Desert beetle, whose back has hydrophilic/hydrophobic contrast for water harvesting by mist condensation in dry desert environments, and some plant leaves that have hierarchical micro/nanostructures to collect or repel liquid water. In this work, we have provided a method for wettability contrast on metals by both nano-flake or needle patterns and tuning of the surface energy. Metals including steel alloys and aluminum were provided with hierarchical micro/nanostructures of metaloxides induced by fluorination and a subsequent catalytic reaction of fluorine ions on metal surfaces in water with various ranges from room to boiling temperature of water. Then, a hydrophobic material was deposited on the structured surfaces, rendering superhydrophobicity. Plasma oxidization induces the formation of superhydrophilic surfaces on selective regions surrounded by superhydrophobic surfaces. We show that wettability contrast surfaces align liquid water within patterned hydrophilic regions during the condensation process. Furthermore, this method could have a greater potential to align other liquids or living cells.