• 대한화학회지
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• 제53권5호
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• pp.505-511
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• 2009

본 논문에서는 구조가 간단하고 생체분야에 응용 가능한 valine, alanine등의 아미노산 분자를 이용하여 수용성 ZnS 나노입자를 합성하였다. 얻어진 고체 생성물들은 XRD, HR-TEM, 및 EDXS분석으로 그 특성을 조사하였다. HR-TEM image 분석의 결과 크기가 대략 3.3에서 3.6 nm 의 입자들이 만들어 졌음을 확인 할 수 있었으며, 나노 입자 표면의 아미노산 분자들은 FT-IR 과 FT-Raman spectrum 을 얻어 결합 모드 등을 분석하였다.

• Membrane and Water Treatment
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• 제6권4호
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• pp.309-321
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• 2015

We report in this study the synthesis of mixed matrix reverse osmosis membranes by interfacial polymerization (IP) of thin film nanocomposite (TFNC) on porous polysulfone supports (PS). This paper investigates the synthesis of ZnO nanoparticles (NPs) using the sol-gel processing technique and evaluates the performance of mixed matrix membranes reached by these aerogel NPs. Aqueous m-phenyl diamine (MPD) and organic trimesoyl chloride (TMC)-NPs mixture solutions were used in the IP process. The reaction of MPD and TMC at the interface of PS substrates resulted in the formation of the thin film composite (TFC). NPs of ZnO with a size of about 25 nm were used for the fabrication of the TFNC membranes. These membranes were characterized and evaluated in comparison with neat TFC ones. Their performances were evaluated based on the water permeability and salt rejection. Experimental results indicated that the NPs improved membrane performance under optimal concentration of NPs. By changing the content of the filler, better hydrophilicity was obtained; the contact angle was decreased from $74^{\circ}$ to $32^{\circ}$. Also, the permeate water flux was increased from 26 to 49 L/m2.h when the content of NPs is 0.1 (wt.%) with the maintaining of lower salt passage of 1%.

• Nano
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• 제13권10호
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• pp.1850118.1-1850118.17
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• 2018

Nanoparticles of the semiconductor catalyst $Cd_xZn_{1-x}S$ were embedded into the metal organic framework MIL-101(Cr) to obtain $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites. These materials not only possess high surface areas and mesopores but also show good utilization of light energy. The ultraviolet-visible diffuse reflectance patterns of $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites showed that $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed good visible light response ability among the synthesized nanocomposites. The photocatalytic performance of the $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites were tested via degradation and mineralization of methylene blue in neutral water solution under light irradiation using a 300W xenon lamp. As a result, using $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) as a catalyst, 99.2% of methylene blue was mineralized within 30 min. Due to the synergistic effect of adsorption by the MIL-101(Cr) component and photocatalytic degradation provided by the $Cd_{0.8}Zn_{0.2}S$ component, the $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) catalyst displayed superior photocatalytic performance relative to $Cd_{0.8}Zn_{0.2}S$ and MIL-101(Cr). Furthermore, $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed excellent stability during photodegradation and exhibited good reusability. The remarkable photocatalytic performance of $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) is likely due to the effective transfer of electrons and holes at the heterojunction interfaces.

• 한국세라믹학회지
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• 제39권12호
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• pp.1119-1123
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• 2002

Nanostructured spinel NiZn ferrites were prepared by the sol-gel method from metal nitrate raw materials. Analyses by X-ray diffraction and scanning electron microscopy showed the average particle size of NiZn ferrite was under 50 nm. The single phase of NiZn ferrites was obtained by firing at 250${\circ}C$, resulting in nanoparticles exhibiting normal ferrimagnetic behavior. The nanostructured $Ni_{1-X}Zn_XFe_2O_4$ (x=0.0∼1.0) were found to have the cubic spinel structure of which the lattice constants ${\alpha}_2$ increases linearly from 8.339 to 8.427 ${\AA}$ with increasing Zn content x, following Vegard's law, approximately. The saturation magnetization $M_s$ was 48 emu/g for x=0.4 and decreased to 8.0 emu/g for higher Zn contents suggesting the typical ferrimagnetism in mixed spinel ferrites. Pure NiZn ferrite phase substituted by Cu was observed before using the additive but hematite phase was partially appeared at $Ni_{0.2}Zn_{0.2}Cu_{0.6}Fe_2O_4$. On the other hand, the hematite phase in this NiZn Cu ferrite was disappeared after using the additive of acethyl aceton with small amount. The saturation magnetization Ms of $Ni_{0.2}Zn_{0.8-y}Cu_yFe_2O_4$(y=0.2∼0.6) as measured was about 51 emu/g at 77K and 19 emu/g at room temperature, respectively.

• 대한화학회지
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• 제60권1호
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• pp.34-38
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• 2016

본 연구는 zinc acetate dihydrate와 sodium hydroxide를 사용하여 ZnO nanoparticles (ZnO NPs)을 합성하였다. 실험에 사용된 방법은 초음파 방법이다. 같은 농도의 각각 zinc acetate dihydrate와 sodium hydroxide를 de-ionized water에 넣고 30분간 교반 하였다. 이 과정에서 생성된 백색의 생성물은 교반 하면서 ultrasonic processor을 사용하여 각각 60분, 120분, 180분, 240분, 360분 처리하였다. 생성물들은 원심분리 후 남은 이온들을 제거하기 위하여 에탄올을 사용하여 여러 번 세척하고, 50 ℃에서 24시간 동안 건조하였다. 합성된 물질들의 결정성과 구조적 특성을 확인하기 위하여 X-ray diffraction spectroscopy(XRD)와 Field emission scanning electron microscopy(FE-SEM)을 사용하였다. 광 촉매 효과는 오염물질 대신 Rhodamin-B를 사용하여 UV 조사하에 암실에서 실험하였다. 광 촉매 효과는 UV-vis spectrometer를 이용하여 확인하였다. XRD 결과 순수한 ZnO가 합성된 것을 확인 하였다. FE-SEM을 통하여 시간이 지남에 따라 구 형태에서 막대형태를 지나 꽃 형태로 변하는 것을 확인 할 수 있었다. 광촉매 특성 결과 꽃 형태를 가진 ZnO NPs가 광 촉매 특성이 가장 우수한 것으로 확인 되었다.

• Advances in nano research
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• 제15권1호
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• pp.67-74
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• 2023

The combination of physical activities and individual skills in sports creates an entertaining and competitive environment governed by a set of rules. In today's world, sports attract significant attention and are approached differently by various groups. Inevitably, injuries occur in sports, significantly impacting an athlete's performance and ability to participate in exercises and competitions. Addressing this issue, one of the crucial measures involves restoring the athlete's ability to engage in sports and compete. Sports rehabilitation serves as a treatment to mitigate the effects of injuries, and when combined with surgery, it can expedite the recovery process. Therefore, the primary objective of this study is to utilize a biocompatible technology for synthesizing zinc oxide (ZnO) nanoparticles in sports rehabilitation, ensuring minimal harm to the environment.

• The Plant Pathology Journal
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• 제39권3호
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• pp.265-274
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• 2023

Citrus black rot is a serious disease of citrus plants caused by Alternaria citri. The current study aimed to synthesize zinc oxide nanoparticles (ZnO-NPs) by chemically or green method and investigate their antifungal activity against A. citri. The sizes of synthesized as measured by transmission electron microscope of ZnO-NPs were 88 and 65 nm for chemical and green methods, respectively. The studied prepared ZnO-NPs were applied, in vitro and in situ, at different concentrations (500, 1,000, and 2,000 ㎍/ml) in post-harvest treatment on navel orange fruits to verify the possible control effect against A. citri. Results of in vitro assay demonstrated that, at concentration 2,000 ㎍/ml, the green ZnO-NPs was able to inhibit about 61% of the fungal growth followed by 52% of chemical ZnO-NPs. In addition, scanning electron microscopy of A. citri treated in vitro with green ZnO-NPs showed swelling and deformation of conidia. Results showed also that, using a chemically and green ZnO-NPs at 2,000 ㎍/ml in situ in post-harvest treatment of orange, artificially-infected with A. citri, has reduced the disease severity to 6.92% and 9.23%, respectively, compared to 23.84% of positive control (non-treated fruits) after 20 days of storage. The out findings of this study may contribute to the development of a natural, effective, and eco-friendly strategy for eradicating harmful phytopathogenic fungi.

• 센서학회지
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• 제31권2호
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• pp.125-130
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• 2022

We describe the importance of zinc oxide nanoparticle (ZnO NP) concentration in the enhancement of electrical properties in a lead sulfide quantum dot (PbS QD)-based shortwave infrared (SWIR) photodetector. ZnO NPs were synthesized using the sol-gel method. The concentration of the ZnO NPs was controlled as 20, 30 and 40 mg/mL in this study. Note that the ZnO NPs layer is commonly used as an electron transport layer in PbS QDs SWIR photodetectors. The photo-to-dark ratio, which is an important parameter of a photodetector, was intensively examined to evaluate the electrical performance. The 20 mg/mL condition of ZnO NPs exhibited the highest photo-to-dark ratio value of 5 at -1 V, compared with 1.8 and 0.4 for 30 mg/mL and 40 mg/mL, respectively. This resulted because the electron mobility decreased when the concentration of ZnO NPs was higher than the optimized value. Based on our results, the concentration of ZnO NPs was observed to play an important role in the electrical performance of the PbS QDs SWIR photodetector.

• 대한화학회지
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• 제59권5호
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• pp.397-406
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• 2015

II-VI 족 무기 화합물 반도체인 ZnO는 폭 넓은 응용분야 때문에 많은 관심을 받고 있다. ZnO는 넓은 밴드갭(3.37 eV)과 큰 excitation binding energy(60 meV)를 가지고 있고 광학특성, 반도체, 압전특성, 자성, 항균성, 광촉매 등 여러 분야에 응용 가능한 물질로 알려져 있다. 특히 광촉매 분야에 적용할 때 재수득의 문제를 위해 자성을 갖는 물질과 core-shell 구조를 이루는 연구가 활발히 진행 되고 있다. 본 연구에서, magnetic core-shell ZnFe₂O₄@ZnO@SiO₂ nanoparticles(NPs)는 3단계 과정을 통해 성공적으로 합성하였다. 합성된 물질들의 구조적 특성을 확인하기 위해 X-ray diffraction(XRD), Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy(FT-IR)을 사용하였다. ZnFe₂O₄ spinel 구조와 ZnO wurtzite 구조는 XRD를 사용하여 확인되었고, 전구체의 농도별 분석을 통해 ZnO 생성 비율을 확인 하였다. 합성된 물질들은SEM을 통하여 표면의 변화를 확인하였다. SiO₂층의 형성과 ZnFe₂O₄@ZnO@SiO₂ NPs의 합성은 FT-IR을 통해 Fe-O, Zn-O 및 Si-O-Si 결합을 확인하였다. 합성된 물질들의 자기적 성질은 Vibrating sample magnetometer(VSM)을 사용 하여 분석하였다. ZnO층과 SiO₂ 층의 형성의 결과는 자성의 증가와 감소로 확인하였다. 합성된 ZnFe₂O₄@ZnO@SiO₂ NPs의 광촉매 효과는 오염물질 대신 methylene blue(MB)를 사용하여 UV 조사 하에 암실에서 실험하였다.

• Bulletin of the Korean Chemical Society
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• 제31권7호
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• pp.1997-2002
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• 2010

ZnSe and ZnS:Mn nanocrystals were synthesized via the thermal decomposition of their corresponding organometallic precursors in a hot coordinating solvent (TOP/TOPO) mixture. The organic surface capping agents were substituted with EDTA molecules to impart hydrophilic surface properties to the resulting nanocrystals. The optical properties of the water-dispersible nanocrystals were analyzed by UV-visible and room temperature solution photoluminescence (PL) spectroscopy. The powders were characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HR-TEM), and confocal laser scanning microscopy (CLSM). The solution PL spectra revealed emission peaks at 390 (ZnSe-EDTA) and 597 (ZnS:Mn-EDTA) nm with PL efficiencies of 4.0 (former) and 2.4% (latter), respectively. Two-photon spectra were obtained by fixing the excitation light source wavelengths at 616 nm (ZnSe-EDTA) and 560 nm (ZnS:Mn-EDTA). The emission peaks appeared at the same positions to that of the PL spectra but with lower peak intensity. In addition, the morphology and sizes of the nanocrystals were estimated from the corresponding HR-TEM images. The measured average particle sizes were 5.4 nm (ZnSe-EDTA) with a standard deviation of 1.2 nm, and 4.7 nm (ZnS:Mn-EDTA) with a standard deviation of 0.8 nm, respectively.