Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Jung Jae Park is active.

Publication


Featured researches published by Jung Jae Park.


Environmental Science & Technology | 2012

Antibacterial and Water Purification Activities of Self-Assembled Honeycomb Structure of Aerosol Deposited Titania Film

Jung Jae Park; Jong Gun Lee; Do Yeon Kim; Joo Hyun Hong; Jae Jin Kim; Seungkwan Hong; Sam S. Yoon

A simple and rapid room-temperature aerosol deposition method was used to fabricate TiO(2) films for photokilling/photdegradation applications. TiO(2) particles were accelerated to supersonic speeds and fractured upon impacting a glass substrate to form a functional thin film, a process known as aerosol deposition. After deposition, the films were annealed at various temperatures, and their photokilling/photodegradation performances following ultraviolet (UV) exposure were evaluated by counting the number of surviving bacterial colonies, and by a methylene blue decolorization test. The photocatalytic performances of all TiO(2) films were obtained under weak UV exposure (0.6 mW/cm(2)). The film density, crystalline phase, and surface roughness (morphology) were measured by scanning electron microscopy, X-ray diffraction, UV-visible spectroscopy, and atomic force microscopy. The unique, self-assembled honeycomb structure of the aerosol deposited films contributed to the increase in surface area because of extreme roughness, which enhances the photokilling and photodegradation performance. Nonannealed films yielded the best photocatalytic performance due to their small crystalline sizes and large surface areas due to increased surface roughness.


ACS Applied Materials & Interfaces | 2013

Thermally Induced Superhydrophilicity in TiO2 Films Prepared by Supersonic Aerosol Deposition

Jung Jae Park; Do Yeon Kim; Sanjay S. Latthe; Jong Gun Lee; Mark T. Swihart; Sam S. Yoon

Superhydrophilic and superhydrophobic surfaces enable self-cleaning phenomena, either forming a continuous water film or forming droplets that roll off the surface, respectively. TiO2 films are well-known for their extreme hydrophilicity and photocatalytic characteristics. Here, we describe nanostructured TiO2 thin films prepared by supersonic aerosol deposition, including a thorough study of the effects of the annealing temperature on the crystal structure, surface morphology, surface roughness, and wetting properties. Powder X-ray diffraction showed that supersonic deposition resulted in fragmentation and amorphization of the micrometer-size anatase (60%)-rutile (40%) precursor powder and that, upon annealing, a substantial fraction of the film (~30%) crystallized in the highly hydrophilic but metastable brookite phase. The film morphology was also somewhat modified after annealing. Scanning electron microscopy and atomic force microscopy revealed rough granular films with high surface roughness. The as-deposited TiO2 films were moderately hydrophilic with a water contact angle (θ) of ~45°, whereas TiO2 films annealed at 500 °C became superhydrophilic (θ ~ 0°) without UV illumination. This thermally induced superhydrophilicity of the TiO2 films can be explained on the basis of the combined effects of the change in the crystal structure, surface microstructure, and surface roughness. Supersonic aerosol deposition followed by annealing is uniquely able to produce these nanostructured films containing a mixture of all three TiO2 phases (anatase, rutile, and brookite) and exhibiting superhydrophilicity without UV illumination.


RSC Advances | 2014

Supersonic aerosol-deposited TiO2 photoelectrodes for photoelectrochemical solar water splitting

Jung Jae Park; Do Yeon Kim; Jong Gun Lee; You Hong Cha; Mark T. Swihart; Sam S. Yoon

Photoelectrochemical (PEC) water-splitting is a promising approach for economical and environmentally friendly hydrogen production. We report here the preparation of nanocrystalline TiO2 films by aerosol deposition (AD) and their performance as photoelectrodes for PEC water splitting. The AD deposited films, 0.5 to 4 μm in thickness, were analyzed to establish the dependence of water splitting performance on film thickness, morphology, and crystallinity. Film thickness and annealing were found to strongly influence the photoelectrochemical water splitting performance. As-deposited TiO2 films exhibited much higher photoelectrochemical activity than annealed TiO2 films. The as-deposited, 3 μm thick TiO2 films exhibited the highest photocurrent density, 93 μA cm−2 at −0.2 V vs. Ag/AgCl, under UV illumination (100 mW cm−2). The same films annealed at 500 °C showed a much lower photocurrent density of 2.9 μA cm−2 at 0.2 V vs. Ag/AgCl.


ACS Applied Materials & Interfaces | 2014

Supersonically blown ultrathin thorny devil nanofibers for efficient air cooling

Seongpil An; Changmin Lee; Minho Liou; Hong Seok Jo; Jung Jae Park; Alexander L. Yarin; Sam S. Yoon

The effect of the supersonically blown below-74 nm nanofibers on cooling of high-temperature surfaces is studied experimentally and theoretically. The ultrathin supersonically blown nanofibers were deposited and then copper-plated, while their surfaces resembled those of the thorny-devil nanofibers. Here, we study for the first time the enhancement of surface cooling in gas in the cases of the forced and natural convection with the help of ultrathin thorny-devil nanofibers. These polymer core-metal shell nanofibers in nanometric scale possess a relatively high thickness of the metal shell and a high effective thermal conductivity, which facilitates heat transfer. The additional surface temperature reduction close to 5 °C in the case of the forced convection in the impinging air jet and close to 17 °C in the case of the natural convection was achieved. Correspondingly, an increase in the value of the heat transfer coefficient of about 41% in the forced convection, and about 20% in the natural convection was achieved due to the presence of the thorny devil electrospun and/or supersonically blown nanofibers.


Advanced Functional Materials | 2014

Self-healing reduced graphene oxide films by supersonic kinetic spraying

Do Yeon Kim; Suman Sinha-Ray; Jung Jae Park; Jong Gun Lee; You Hong Cha; Sang Hoon Bae; Jong-Hyun Ahn; Yong Chae Jung; Soo Min Kim; Alexander L. Yarin; Sam S. Yoon


Ceramics International | 2014

Superhydrophobic surface decorated with vertical ZnO nanorods modified by stearic acid

Annaso B. Gurav; Sanjay S. Latthe; Rajiv S. Vhatkar; Jong Gun Lee; Do Yeon Kim; Jung Jae Park; Sam S. Yoon


Journal of Aerosol Science | 2011

Optimization of supersonic nozzle flow for titanium dioxide thin-film coating by aerosol deposition

Min Wook Lee; Jung Jae Park; Do Yeon Kim; Sehyoun Yoon; Honggon Kim; D.H. Kim; Scott C. James; Sanjeev Chandra; Thomas W. Coyle; J.H. Ryu; W.H. Yoon; D.S. Park


Journal of Thermal Spray Technology | 2013

Cold Spray Deposition of Copper Electrodes on Silicon and Glass Substrates

Do Yeon Kim; Jung Jae Park; Jong Gun Lee; Donghwan Kim; Sung Ju Tark; SeJin Ahn; Jae Ho Yun; Jihye Gwak; Kyung Hoon Yoon; Sanjeev Chandra; Suk Goo Yoon


Journal of Thermal Spray Technology | 2011

Supersonic Nozzle Flow Simulations for Particle Coating Applications: Effects of Shockwaves, Nozzle Geometry, Ambient Pressure, and Substrate Location upon Flow Characteristics

Jung Jae Park; Min Wook Lee; Sam S. Yoon; Ho Young Kim; Scott C. James; Stephen D. Heister; Sanjeev Chandra; Woon Ha Yoon; Dong Soo Park; Jungho Ryu


Ceramics International | 2014

Graphene–titania films by supersonic kinetic spraying for enhanced performance of dye-sensitized solar cells

Do Yeon Kim; Bhavana N. Joshi; Jung Jae Park; Jong Gun Lee; You Hong Cha; Tae Yeon Seong; Suk In Noh; Hyo Jin Ahn; Salem S. Al-Deyabe; Sam S. Yoon

Collaboration


Dive into the Jung Jae Park's collaboration.

Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Mark T. Swihart

State University of New York System

View shared research outputs
Researchain Logo
Decentralizing Knowledge