Yoonmook Kang

Vertically aligned CdTe nanorods were fabricated by electrodeposition and were applied for the active layer of solar cells after being combined with poly(3-octylthiophene) (P3OT), a conjugated polymer. The electrodeposited CdTe showed an n-type behavior with the electric resistivity and the electron density of 2×106Ωcm, 1.3×1010cm−3, respectively. Quantum efficiency curve of the hybrid solar cells exhibited a peak at the same wavelength as the optical absorption for CdTe nanorods. The hybrid sol

This study evaluated the impact of partial shading on CuInxGa(1-x)Se2 (CIGS) photovoltaic (PV) modules equipped with bypass diodes. When the CIGS PV modules were partially shaded, they were subjected to partial reverse bias, leading to the formation of hotspots and a possible occurrence of junction damage. In a module with a cadmium sulfide buffer layer, hotspots and wormlike defects were formed. The hotspots were formed as soon as the modules were shaded; the hotspots caused permanent damage (w

Hybrid tandem solar cells offer the benefits of low cost and full solar spectrum utilization. Among the hybrid tandem structures explored to date, the most popular ones have four (simple stacking design) or two (terminal/tunneling layer addition design) terminal electrodes. Although the latter design is more cost-effective than the former, its widespread application is hindered by the difficulty of preparing an interface between two solar cell materials. The oldest approach to the in-series bond

Solar energy has gained prominence because of the increasing global attention received by renewable energies. This shift can be attributed to advancements and innovations in solar cell technology, which include developments of various photovoltaic materials, such as thin film and tandem solar cells, in addition to silicon-based solar cells. The latter is the most widely commercialized type of solar cell because of its exceptional durability, long-term stability, and high photoconversion efficien

In the photovoltaic (PV) industry, module manufacturers have begun to install bifacial cells into monofacial modules because of their lower production costs relative to monofacial cells. This is linked mainly to a 65.3% reduction in rear aluminum paste consumption and the corresponding 0.5 cent/wafer cost reduction for M4 (161.7 × 161.7 mm2) size wafers. Therefore, this study compared the performance of monofacial PV modules with the monofacial cells as a reference group and bifacial cells as th

Recently, titanium oxide has been widely investigated as a carrier-selective contact material for silicon solar cells. Herein, titanium oxide films were fabricated via simple deposition methods involving thermal evaporation and oxidation. This study focuses on characterizing an electron-selective passivated contact layer with this oxidized method. Subsequently, the SiO2/TiO2 stack was examined using high-resolution transmission electron microscopy. The phase and chemical composition of the titan

Radio frequency (RF) magnetron-sputtered TiO2 (RS-TiO2) is investigated as a hole-blocking layer for perovskite solar cells. RS-TiO2 shows conformal, dense, and efficiently electron transferable properties. Power conversion efficiency (PCEs) of 20.9% were obtained with high reproducibility. RS-TiO2 also showed potential in the up-scaling process, transparent perovskite, and perovskite/silicon 4-terminal tandem solar cells. With increasing active area 40 times from 0.075 cm2 to 3 cm2 without divi

A high contact resistance for screen-printed contacts was observed when a conventional Ag paste was used on a boron emitter. The results of this study suggest that electron injection during firing is one of the processes that contribute to a lower contact resistance. Larger quantities of Ag precipitates formed upon electron injection into the boron emitter, which was confirmed by observing Ag crystallite or dendrite structures on the boron and by measuring the contact resistance between the boro