Cheolhyun Lim

SiO2 나노입자가 분산된 TiO2 나노섬유의 제작 및 광촉매 특성 분석

본 연구에서는 전구체 각각의 독립제어가 가능한 이성분계 금속산화물을 얻기 위해 졸-겔법으로 합성한 실리카 나노입자를 TiO2 전구체와 교반시켜 전기방사법을 이용하여 실리카가 고르게 분산된 TiO2 나노섬유를 성공적으로 제작하였다. 제작된 나노섬유는 FE-SEM, XRD, EDS를 이용해 구조적 특성분석과 UV-VIS, 광촉매 반응기를 통해 광촉매특성 분석을 하였다. 그 결과, 실리카가 분산된 TiO2 나노섬유는 실리카가 분산되지 않은 TiO2 나노섬유 보다 광촉매효율이 10% 가량 향상되었다. 이는 실리카 나노입자가 첨가됨으로써 TiO2가 흡수하지 못하는 380~440 nm 가시광선영역을 흡수하여 광학적 특성 향상되었으며 Ti와 Si 두 금속산화물간에 Bronsted acid site가 생성되어 OH 라디칼을증가시킴으로써 광조사에 의해 여기된 전자를 잡아 재결합 손실을 억제하는 역할을 하여 화학적 특성이 개선되어 광촉매 효율이 증가되었을 것으로 사료된다.− In this study, we suggest a facile method to control conditions of single component independently when preparing consisting two-component metal oxides nanofiber by simply dispersing nanoparticles in precursor solution. The well dispersed SiO 2 nanoparticles in TiO 2 nanofibers were successfully synthesized through a simple electrospinning process. The as-synthesized nanodfibers were investigated via FE-SEM, XRD and EDS for structural studies, furthermore, the analysis of UV-VIS and photocatalytic activity were carried out for demonstrate the effect of SiO 2 nanoparticles dispersed in TiO 2 nanofibers. As a result, TiO 2 nanofibres dispersed with SiO 2 nanoparticles have enhanced photocatalytic activity than that of TiO 2 nanofibres only. In this strategy, the introduction of SiO 2 nanoparticles in TiO 2 nanofibers were attribute to enlarge absorption in the visible region (380~440 nm). Additionally, Brønsted acid sites generated in each metal oxide of Ti and Si increase OH radicals efficiently as well as it limit recombination loss by holding photogenerated electrons for high efficient photocatalytic activity.

Characterization of Low-temperature Conductive Films Bonded PV Modules and Its Field Test

In this paper, PV modules using a low-temperature conductive film(LT-CF) as a bonding material between a cell and a solder free ribbon were produced and chracterized, which is more environmental-friendly, cost effective and high efficient. Mainly, filed electrical performance of PV modules using three different types of bonding material; a convetional solder ribbon(SR), a LT-CF and a light-capturing Ribbon(LCR) were compared to comfirm the feasibility of LT-CF as a bonding material. The filed test were conducted for 3 months and results were discussed in terms of amount of output energy production and efficiency.