Introducing new technologies into infrastructure (wind turbines, electric vehicles, low-carbon materials and so on) often demands materials that are ‘critical’; their supply is likely to be disrupt...

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Critical materials for infrastructure: local vs global properties

Application of X-ray diffraction to identify the phases formed during lead stabilization and resource recovery

Improvement on the melt-texturing performance of a (Y,Ta)0.5BaO3–YBa2Cu3Oy composite with superconductor applications

본 논문은 동시진공증발법으로 제작된 시편을 500℃ 에서 열처리한 시편은 기공이 많이 발생되어 결정결함이 발생 되었어 열처리 시 Se분위기하에서 실행을 해야 된다는 것을 알 수가 있었다. 기판온도를 430℃ , 460℃ , 480℃ , 500℃ 로 변화주어 제작된 시편을 열처리 한 결과 결정입자 크기가 증가되어 밀도가 향상되었다. 그리고 XRD 분석결과, 열처리 후에 Cu2Se상이 제거되었으며 열처리 전·후의 흡수지수는 큰 변화가 없었다. 이것은 흡수지수는 열처리보다 시편 두께에 의해 결정된다는 것을 알 수가 있었다.

열처리에 의한 Cu(In,Ga)Se₂ 태양전지 특성에 관한 연구

The improvement of preparation process of YBa2Cu3Ox superconductor and its conducting properties is important for practical applications. In this study, the additives such as Ag2O and PbO were used to improve the preparation conditions of YBa2Cu3Ox superconducting bulk samples and the properties of YBa2Cu3Ox superconductors prepared with powders using sol-gel method and solid state reaction method were studied. The effects of the different powders and the additives to the density, grain alignment, and porosity of samples, that affect the critical current density of superconductor, also have been investigated. It is found that the properties of YBa2Cu3Ox prepared with sol-gel synthesized powder and the additives showed better superconductivities than those of conventionally prepared superconductors.

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Preparation of Yba 2 Cu 3 O x Superconductor Prepared with Additives of PbO and Ag 2 O

In this paper, the thin film was prepared by using co-evaporation method in four different substrate temperatures , , and . When the substrate temperature was at and , the single-phase was crystallized. As the temperature increased, it was shown that the thickness of the thin film was decreased with increment of the hall coefficient. When the sample was prepared at of the subsrate temperature, the values of band gap energy (Eg), sheet resister and resistivity were measured 0.99 eV, and , respectively.

Properties of CuInSe 2 Thin Film with Various Substrate Temperatures

In this paper, CdS thin films for the use of window layer in solar cell were fabricated by vacuum evaporation method to improve the reproducibility, The electrical and optical properties of thin films with the variations of substrates temperature and the variations of the film thickness were investigated. As increasing the substrates temperature the resistivities of films were increased. The samples transmissivity were shown over 70% when the wavelength were above 500 nm. In the films with 280 nm thickness, its transmissivity were reached 100%. The resistivities of the samples were decreased as increasing its thickness.

Electrical and Optical Properties of CdS Thin Film with Different Substrate Temperatures

This research is based on fabricating Cu(In,Ga) thin-film by co-evaporation method. On - stage, phase appeared when the substrate temperature reached to , however, there was small effect between the substrate temperature and absorbency spectrum on , - stage because the average thickness of the thin-film was or higher. SEM and XRD was measured on and stage and it showed as the substrate temperature increases, the density of the crystal structure increased with the decreament of the vacancy. Furthermore, the formation of Cu(In0.7Ga0.3) phase showed at and .

/pdf/a-study-on-cu-in-ga-se-2-thin-film-fabarication-using-to-co-5gu4wi3mxd.pdf

A study on Cu(In,Ga)Se 2 thin film fabarication using to co-evaporation

In this paper, as an attempt to improve the preparation conditions of superconducting bulk samples, the properties of superconductor depending on the particle size of YBCO powder and as an additive have been investigated, and a study on the effects of additive to the density, grain alignment, and porosity of samples that affect the critical current of superconductor has been performed. In order to prepare superconductor, powder synthesized by sol-gel method, showing a size distribution of 0.2~1 was used. The added to promote grain growth and to decrease porosities and weak links between grain boundaries of superconductors. In the samples prepared by sol-gel synthesized powder with 10, 20, and 30 wt% conductive additives, the sample with 20 wt% obtained the highest critical current of 4.74 A, showing 20 wt% higher critical current than that with solid state synthesized powder.

Jung-Cheul Park

Papers

Preparation of Yba 2 Cu 3 O x Superconductor Prepared with Additives of PbO and Ag 2 O

Properties of CuInSe 2 Thin Film with Various Substrate Temperatures

Electrical and Optical Properties of CdS Thin Film with Different Substrate Temperatures

A study on Cu(In,Ga)Se 2 thin film fabarication using to co-evaporation

Superconductor Preparation by use of YBa 2 Cu 3 Ox powder and BaPbO 3 Additive