• Current Photovoltaic Research
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• 제10권2호
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• pp.33-38
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• 2022

Planner configuration thin film solar cells (TFSCs) with SnS/CdS heterojunction performed a lower short-circuit current (J_SC). In this study, we have demonstrated a path to overcome deficiency in J_SC by the incorporation of Se in the SnS absorber. We carried out the incorporation of Se in VTD grown SnS absorber by rapid thermal annealing (RTA). The diffusion of Se is mostly governed by RTA temperature (T_RTA), also it is observed that film structure changes from cube-like to plate-like structure with T_RTA. The maximum J_SC of 23.1 mA cm^-2 was observed for 400℃ with an open-circuit voltage (V_OC) of 0.140 V for the same temperature. The highest performance of 2.21% with J_SC of 18.6 mA cm^-2, V_OC of 0.290 V, and fill factor (FF) of 40.9% is observed for a T_RTA of 300℃. In the end, we compare the device performance of Se- incorporated SnS absorber with pristine SnS absorber material, increment in J_SC is approximately 80% while a loss in V_OC of about 20% has been observed.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.796-798
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• 2002

In these days, the interruption capability of some circuit breakers, which are installed in the transmission systems, is getting lower than the magnitude of the fault current because of continuous increase of power demand and relatively short power line which was installed in forms of mesh network As a result of these situations, fault current limiters (FCLs) are strongly necessary. There are various types which is investigated around the world, and new power apparatuses that have been newly considered and developed by many manufactures. In this paper, we considered resistive superconducting fault current limiters with YBCO thin films. The resistive limiters utilize a transition of YBCO films from superconducting to normal state caused by exceeding the critical current. By means of newly occurred impedance, the fault current will be limited effectively. Generally, a few current path patterns are available for YBCO films to enhance the current limiting performance of YBCO films. In this paper. the meander-type and the bi-spiral-type were used for current paths of YBCO flims. When YBCO films are quenched into the normal state, bubbles could be observed on the surface of YBCO films. Using our high-speed camera, the number of bubbles and the size of bubbles could be visualized and the relation between bubbles and current density was analyzed. By means of moving pictures of bubbles, we observed how the quench extended or how the heat was conducted in films.

• 한국세라믹학회지
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• 제47권2호
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• pp.106-112
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• 2010

This paper presents some experimental results on incubation time for massive hydriding of Zr alloys with oxide thickness. Oxide effects experiments on massive hydriding reaction of commercial Zr alloy claddings and pre-oxidized Zr alloys with hydrogen gas were carried out in the temperature range from 300 to $400^{\circ}C$ with thermo-gravimetric apparatus. Experimental results for oxide effects on massive hydriding kinetics show that incubation time is not proportional to oxide thickness and that the massive hydriding kinetics of pre-filmed Zr alloys follows linear kinetic law and the hydriding rate are similar to that of oxide-free Zr alloys once massive hydriding is initiated. There was a difference in micro-structures between oxide during incubation time and oxide after incubation time. Physical defects such as micro-cracks and pores were observed in only oxide after incubation time. Therefore, the massive hydriding of Zr alloys seems to be ascribed to short circuit path, mechacical or physical defects, such as micro-cracks and pores in the oxide rather than hydrogen diffusion through the oxide resulting from the increase of oxygen vacancies in the hypostoichiometric oxide.

• 한국전기전자재료학회논문지
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• 제35권4호
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• pp.398-406
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• 2022

In order to increase the electrochemical performance of thermal battery anode, LIFT anode having the same weight but a larger lithium content in electrodes was fabricated by mixing lithium, iron and titanium. By applying these electrodes, a single cell and a thermal battery were prepared, and the effect of LIFT anode on electrochemical performance was evaluated. The LIFT-applied single cell presented a better cell performance than LIFe-applied single cell at 500℃ and 550℃. The discharge performance of LIFT-applied single cell, which included the operating time (787s), specific capacity (1,683 Asg^-1), and electrode utilization (80.7%), was improved collectively compared to the LIFe applied single cell (736s, 1,245 As g^-1, and 74.6%) at 500℃. As the discharge progressed, the internal resistance of LIFT anode decreased, because the lithium migration path was formed due to the presence of large titanium particles among iron particles. These results were analyzed in terms of the microstructure of electrode using SEM. Energy density of LIFT-applied single cell also increased by 10% to 142.1 Wh kg^-1 compared to that of LIFe-applied single cell (127.4 Wh kg^-1). In addition, the LIFT-applied single cell presented a stable discharge performance for 6,500s without a short circuit which could occur by molten lithium under an open circuit voltage condition with a high pressure (4 kgf cm^-2). As observed in the high temperature thermal battery performance tests, the voltage and specific capacity of LIFT-applied thermal battery are superior to those of LIFe-applied thermal batteries, indicating that the energy density of LIFT-applied thermal batteries should remarkably increase.

• 공업화학
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• 제22권2호
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• pp.190-195
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• 2011

다중층을 형성하여 광자를 가두는 효과와 산란층의 효과를 보고, $TiCl_4$ 처리를 통해 전극에서의 전자의 재결합이 줄어드는 정도와 그에 따른 효과를 알아보기 위하여 여러 가지 방법으로 $TiO_2$ 전극을 형성하고, 가장 최적의 전극 조건을 알아보았다. 각 전극의 특성을 알기 위해서 I-V 곡선, UV-VIS 분광기, EIS, IPCE를 측정하였다. 그 결과, I-V 곡선을 통해 한 층 보다는 다중층이 효율이 더 높은 것을 확인할 수 있었고, 기판 표면과 전극표면에 $TiCl_4$ 처리를 함으로써 EIS분석을 통해 반응저항이 감소하여 효율이 증가함을 확인할 수 있었다. 여러 전극 조건 중 산란층을 지닌 전극이 기본 한 층을 사용한 전극의 효율보다 약 19% 정도 높아짐을 확인하였다. 이러한 효율의 증가는 장파장을 투과하는 빛이 산란층을 통과할 때 전자 이동 경로가 길어지게 되어 단락전류의 값을 증가시키기 때문이다. 이에 따라, $J_{SC}$는 약 10% 정도 증가하였으며, IPCE는 최대 피크에서 약 12%가 향상되는 특성을 보였다.