• 폴리머
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• 제38권2호
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• pp.150-155
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• 2014

Polycaprolactone(PCL)은 생분해성 고분자로 인장강도, 신장률, 충격강도 등의 기계적 물성이 우수하다. $TiO_2$ (titanium dioxide) nanoparticle은 친수성으로 밀도가 높고 생체적합성이 우수하다. 본 연구에서는 PCL과 $TiO_2$(titanium dioxide) nanoparticle을 이용하여 salt-leaching방법으로 3차원 다공성 지지체를 제작하였다. 제작한 지지체를 FESEM, FTIR, TGA, 압축강도 측정 등을 통해 물성을 분석하였다. $TiO_2$ nanoparticle에 의해 물흡수도와 팽윤도는 감소하였으나 압축강도는 증가하였다. CCK-8 assay를 통해 세포의 증식률을 확인한 결과, $TiO_2$ nanoparticle에 의한 세포 독성은 없는 것으로 확인되었다. 이러한 연구결과는 PCL/$TiO_2$ nanoparticle 지지체의 생체재료로 사용가능성을 제시하였다.

• Journal of Electrical Engineering and Technology
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• 제10권6호
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• pp.2343-2347
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• 2015

This paper reports the effect of Titanium dioxide (TiO₂) nanoparticles on a TiO₂ sol-gel Schottky diode. TiO₂ nanoparticles were blended with TiO₂ sol-gel to fabricate the Schottky diode. TiO₂ nanoparticles showed strong anatase and rutile X-ray diffraction peaks. However, the mixture of TiO₂ sol-gel and TiO₂ nanoparticles exhibited no anatase and rutile peaks. The forward current of the Schottky diode drastically increased as the concentration of TiO₂ nanoparticles increased up to 10 wt. % and decreased after that. The possible conduction mechanism is more likely space charge limited conduction.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.760-763
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• 2002

Nanoparticle size of Titanium dioxide thin films was prepared by novel method. Particle size and surface structure of $TiO_2$ thin films were investigated by atomic force microscopy(AFM), scanning electron microscopy(SEM). All thin films process were prepared at room temperature. Particle size was reduced from 100 to 30nm with increasing amount of $Ti[OCH(CH_3)_2]_4$ observed by AFM images. All thin films were irradiated for 5 minutes by white light. Increasing the annealing temperature, particles size was increased. In the $TiO_2$(40%) thin films was annealed at $300^{\circ}C$ for 30minutes, the particle size was about 10nm.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.756-759
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• 2002

Nanoparticles of titanium dioxide$(TiO_2)$ were prepared by photochemical synthesis. Surface structure, morphology and particle size of $TiO_2$ thin films were investigated by UV-VIS spectrophotometer, scanning electron microscopy(SEM) and transmission electron microscopy(TEM). All process was prepared at room temperature. The absorption peak of the films was showed at 360nm and $TiO_2$ nanopaticle size was observed at about 20~30nm. Electron diffraction ring patterns of $TiO_2$ nanoparticles and crystallographic spacing were observed by TEM. As a result, crystallographic spacing was about 3.6A in HR-TEM micrographs.

• Environmental Analysis Health and Toxicology
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• 제23권4호
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• pp.285-290
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• 2008

Effects of titanium dioxide nanoparticles on blood coagulation and platelet aggregation were investigated using diluted whole blood and platelet rich plasma (PRP) solution prepared from human and rat blood, respectively. Blood coagulation was monitored by using a whole blood impedance aggregometer and titanium dioxide nanoparticle (10, 20, and 40 ppm) did not show any effect on the coagulation both in human and in rat blood. When platelet aggregation was measured by turbidometric method after addition of titanium dioxide nanoparticles to PRP solution with final concentrations of 1, 5 and 10 ppm. no aggregation was observed.

• 한국전기전자재료학회논문지
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• 제16권2호
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• pp.125-130
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• 2003

TiO$_2$ nanoparticles were prepared by photochemical synthesis in the dry toluene. The shape and size of the amorphous TiO$_2$ nanoparticles were investigated by transmission electron microscope. The particle size was varied by the contents of the titanium (IV) isopropoxide in dry toluene. Especially networked TiO$_2$ particles were formed from 40% titanium (IV) isopropoxide solution. The optical absorption spectra, photoluminescence, and PL excitation spectra of TiO$_2$ in dry toluene were obtained. The were shifted to the short wavelength as the contents of TiO$_2$ were increased. PL excitation had the peak at the wavelength regions is which the absorption increased steeply.

• 한국재료학회지
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• 제29권3호
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• pp.183-188
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• 2019

Flexible dye-sensitized solar cells using binder free $TiO_2$ paste for low temperature sintering are developed. In this paste a small amount of titanium gel is added to a paste of $TiO_2$ nanoparticle. Analysis of titanium gel paste prepared at $150^{\circ}C$ shows that it has a pure anatase phase in XRD and mesoporous structure in SEM. The formation of the titanium gel 1-2 nm coated layer is confirmed by comparing the TEM image analysis of the titanium gel paste and the pristine paste. This coating layer improves the excited electron transfer and electrical contact between particles. The J-V curves of the organic binder DSSCs fabricated at $150^{\circ}C$ shows a current density of $0.12mA/cm^2$ and an open-circuit voltage of 0.47 V, while the titanium gel DSSCs improves electrical characteristics to $5.04mA/cm^2$ and 0.74 V. As a result, the photoelectric conversion efficiency of the organic binder DSSC prepared at low temperature is as low as 0.02 %, but the titanium gel paste DSSCs has a measured effciency of 2.76 %.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.423-428
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• 2010

To reduce polarization of electrochemical capacitor based on carbon nanotube, titanium oxide nanoparticles were deposited by ultrasound. The pore distribution of $TiO_2$/CNT nanoparticle exhibited surface area of $341\;m^2g^{-1}$ when $TiO_2$ content was 4 wt %, which was better than that of pristine CNT with surface area of $188\;m^2g^{-1}$. The analyses indicated that titanium oxide (particle diameter < 20 nm) was deposited on the CNT surface. The electrochemical performance was evaluated by using cyclic voltammetry (CV), impedance measurement, and constant-current charge/discharge cycling techniques. The $TiO_2$/CNT composite electrode showed relatively better electrochemical behaviors than CNT electrode by increasing the specific capacitance from $22\;Fg^{-1}$ to $37\;Fg^{-1}$ in 1 M $H_2SO_4$ solution. A symmetric cell assembled with the composite electrodes showed the specific capacitance value of $11\;Fg^{-1}$ at a current loading of $0.5\;mAcm^{-2}$ during initial cycling.

• Membrane and Water Treatment
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• 제9권6호
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• pp.481-487
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• 2018

Membrane clogging or fouling of the membrane caused by organic, inorganic, and biological on the surface is one of the main obstacles to achieve high flux over a long period of the membrane filtration process. So researchers have been many attempts to reduce membrane fouling and found that there is a close relationship between membrane surface hydrophilicity and membrane fouling, such that the same conditions, a greater hydrophilicity were less prone to fouling. Nanotechnology in the past decade is provided numerous opportunities to examine the effects of metal nanoparticles on the both hydrophilic and antibacterial properties of the membrane. In the present study the improvement of hydrophilic and antimicrobial properties of the membrane was evaluated by adding nanoparticles of titanium dioxide and copper oxide. For this purpose, 4% copper oxide and titanium dioxide nanoparticles with a ratio of 0, 30, 50, and 70% of copper oxide added to the polymeric membrane and compare to the pure polymeric membrane. Comparison experiments were performed on E. coli PTCC1998 in two ways disc and tube and also to evaluate membrane hydrophilic by measuring the contact angle and diameter of pores and analysis point SEM has been made. The results show that the membrane-containing nanoparticle has antibacterial properties and its impact by increasing the percentage of copper oxide nanoparticles increases.

• 한국세라믹학회지
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• 제50권6호
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• pp.489-494
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• 2013

Nano-sized titanium oxide powders were synthesized by a polymer matrix technique using pulp and Titanium tetraisopropoxide (TTIP) as starting materials. The synthesized powders were characterized by XRD and FE-SEM. The particle size of the powders was controlled by preparation conditions, such as heat treatment temperature and time. After investigating various drying and heat treatment conditions, 50-100 nm sized homogeneous titanium oxide particles were obtained by treating at $600^{\circ}C$ for 1 h. The crystallization and rapid growth of particles was accelerated by increasing heat treatment temperature and time. Anatase phase generated below $600^{\circ}C$ transformed to the rutile phase with increasing heat treatment temperature. Moreover, above $800^{\circ}C$, heat treatment time had a very large influence on particle growth, and changing the heating condition also had a large influence on crystal growth.