Heterojunction technology (HJT) solar cells, known for their high efficiency, utilize a heterojunction structure combining crystalline and amorphous silicon layers. Due to the structural characteristics of HJT cells, low-temperature processing is necessary for their production, which presents challenges in electrode formation compared to traditional high-temperature methods. Low-temperature curable silver pastes, essential for this process, generally have lower conductivity than high-temperature sintered electrodes due to reduced silver particle connectivity and residual binder. To solve these problems, low-temperature curable pastes are typically manufactured with increased silver content, which has the effect of improving conductivity, but at the same time increases the production cost. Therefore, it is crucial to find ways to enhance the electrical properties of these pastes without increasing the silver content. In this study, the resistivity of low-temperature curable pastes was evaluated by mixing silver particles with different size distributions. Four types of silver particles with varying shapes and size distributions were used to formulate three types of silver-mixed pastes. After screen-printing and curing, the resistance and thickness of the cured pastes were measured. The relationship between the silver particles used and the calculated resistivity was analyzed, confirming that resistivity can be improved without increasing the silver content.

Recently, the need for alternative energy sources has been increasing due to environmental pollution caused by the rising use of fossil fuels. Among alternative energies, solar cells that utilize endless sunlight are attracting significant attention. In particular, organic solar cells offer advantages such as low cost, solution processing, and flexible device fabrication. However, they suffer from low power conversion efficiency and instability due to a limited absorption spectrum. In response, high efficiency has been achieved using PM6:Y6, a photoactive layer organic semiconductor with a broad absorption range in the near-infrared region, reaching 18.2% efficiency with electron transport layers. Although organic solar cells show high efficiency, their relatively low stability limits their commercialization. This review will introduce the inorganic/organic electron transport layers of PM6:Y6-based organic solar cells and discuss the impact of light and heat among the various factors contributing to their low stability.

Metal halide perovskites have attracted tremendous attention due to their superior photoelectric properties, which led to light-emitting diodes (LEDs) applications. To enhance the poor performance of blue LEDs compared to green and red LEDs, quasi-2-dimensional perovskites, which have the energy funneling effect, were chosen. To maximize the energy funneling effect, it is necessary to rearrange the 2-dimensional phase distribution. The shortened energy transfer pathway can improve radiative recombination. Here, we introduce a variety of metal halide additives for high-performance perovskite LEDs.

An anti-solvent additive method is one of process for passivating defect to improve the crystal quality, stability, and suppressing charge losses. The functional groups of additives can interact with perovskite ions and it can prevent ion vacancies and defects. However, due to different polarity between additives and anti-solvent, the additives have less solubility in the anti-solvent. Herein, we propose a method to optimize the dissolution of additives in anti-solvents, and observe the characteristics of perovskite films produced by the anti-solvent additive method through spectroscopy analysis. We obtained the solubility of additives through absorbance and predicted the unsaturation concentration. In addition, the passivated perovskite films by optimized concentration showed different passivation effects according to additives.

The electrochemical carbon dioxide reduction reaction (eCO₂RR) has garnered significant attention as a promising approach for converting carbon dioxide, a major greenhouse gas, into valuable carbon-based products. Among available catalysts, copper (Cu) stands out as the potential candidate capable of producing C₂₊ compounds during eCO₂RR. However, its practical application is hindered by limitations such as low stability, efficiency, and selectivity, requiring further investigation. This study addresses these challenges by employing a gas diffusion electrode (GDE) to enhance the efficiency and selectivity of Cu-based catalysts. The GDE@Cu electrode was fabricated via electrodeposition, and its eCO₂RR performance was systematically evaluated under varying Cu deposition times to optimize the fabrication process. The findings demonstrated that the GDE@Cu electrode achieved a Faradaic efficiency (FE) exceeding 50% for ethanol production, underscoring the efficacy of electrodeposited Cu on GDE in facilitating C₂ hydrocarbon generation. This optimized strategy highlights the potential of Cu-based catalysts for improved performance in eCO₂RR applications.

The BIPV module can directly convert solar energy into electricity, thereby reducing the energy consumption of buildings, and it is suitable for domestic distribution as it does not require separate installation land, which is ideal for a country with limited land area and high population density. However, conventional silicon (Si) photovoltaic (PV) modules have used a monotonous black appearance to maximize solar energy conversion, resulting in design issues that hindered market activation. In response, methods for colorizing BIPV modules have been intensively studied to promote market adoption. However, the color of solar cells is achieved by reflecting or transmitting visible light through the cells, which implies optical losses from the perspective of solar energy conversion. To find the optimal balance between efficiency and aesthetics, the color and brightness must be determined in a way that minimizes optical losses and maximizes conversion efficiency. In this study, a colored flexible module suitable for BIPV was fabricated and its characteristics were analyzed. The yellow film showed the narrowest transmittance reduction band and the lowest degree of decrease in transmittance, making it ideal for minimizing efficiency loss compared to other colored products.

This study investigates the power prediction and performance of bifacial photovoltaic (PV) systems installed at four demonstration sites, including a fruit farm, a regular field, a rice field, and a salt field. A fence-type bifacial PV system was installed at each site, and power generation was predicted using bifaciality factors (BF) ranging from 0.50 to 0.75. The predicted results were then compared with actual power data collected over the demonstration period. The results revealed that the impact of bifaciality factors on the accuracy of power generation predictions varied by site. At the fruit farm and regular field, higher BF values resulted in larger discrepancies between predicted and measured power generation, with an overestimation of predicted values. This indicates that environmental factors, such as shading and reflectivity, negatively impacted the rear-side power generation of bifacial modules in these locations, suggesting the need for further optimization of BF application in such environments. In contrast, the rice field and salt field exhibited a decrease in prediction error as BF values increased. Notably, the rice field demonstrated the most accurate prediction at a BF value of 0.65, with an error rate of 0%, while the salt field achieved a minimal error rate of 1% at a BF value of 0.75. These results suggest that high-reflectivity environments, such as the salt field, benefit from higher BF values, leading to more accurate power generation predictions.

Photoelectrochemical (PEC) water splitting offers an eco-friendly method to convert solar energy into hydrogen, with recent advancements improving efficiency. However, despite direct hydrogen production on photocathode surfaces, research into high-performance, stable photocathode-specific catalysts remains limited. In this study, we optimized a NiMo hydrogen evolution reaction (HER) catalyst on Cu₂O-based photocathodes using a photoelectrodeposition (PED) method to enhance PEC water-splitting efficiency. Key deposition parameters, including light, current density, applied voltage, and time, were systematically controlled to ensure uniform NiMo catalyst deposition without post-treatments. Under simulated 1-sun illumination, the optimized NiMo catalyst achieved 93% of the performance of conventional Pt catalysts and maintained stable hydrogen production for over 20 hours. Electrochemical analysis confirmed superior PEC performance of the NiMo catalyst, particularly at a fixed current density of -1.5 ㎂ cm^-2. This study introduces a noble metal-free catalyst deposition method, advancing solar-to-hydrogen conversion efficiency and long-term PEC device stability.

As companies increasingly join RE100 campaign to overcome the climate crisis, the importance of achieving RE100 in industrial complexes, which account for over 70% of Korea's manufacturing exports, is growing to maintain export competitiveness. This paper analyzed the economic feasibility of each participant in the renewable energy electricity storage and sales business that utilizes surplus power from solar power generation of a nearby school to achieve RE100 in industrial complexes. Results show that under current market conditions, it is challenging to ensure economic viability without reduced ESS installation costs or policy support. However, the introducing a real-time market, renewable energy bidding systems, and electricity prices linked to these systems showed potential for economic improvement. Therefore, institutional support is deemed necessary in the initial stages to promote the business. This approach is expected to contribute to enhancing social value by effectively utilize surplus power, contribute to achieving RE100, promote ESS deployment.