Faith After Sewol

On April 16, 2014, in the south sea of Korea, a ferry named Sewol sank and 304 people were killed, including 250 high school students who were on their field trip. Koreans witnessed painfully and powerlessly the victims dying in the cold water, which terrified and traumatized them. It was not simply a marine accident but culminating tragic event caused by decades of accumulated social problems and evils. Because of the complexity behind the tragedy, there were mixed responses to the suffering of the victims and their bereaved families, such as empathy, apathy, and antipathy, sometimes sequentially and sometimes simultaneously. The purpose of this essay, therefore, is to examine these complex social and religious responses to the tragedy, focusing on the Christian bereaved families’ struggle to make sense of their faith in the face of their unspeakable suffering

Faith After Sewol

On April 16, 2014, in the south sea of Korea, a ferry named Sewol sank and 304 people were killed, including 250 high school students who were on their field trip. Koreans witnessed painfully and powerlessly the victims dying in the cold water, which terrified and traumatized them. It was not simply a marine accident but culminating tragic event caused by decades of accumulated social problems and evils. Because of the complexity behind the tragedy, there were mixed responses to the suffering of the victims and their bereaved families, such as empathy, apathy, and antipathy, sometimes sequentially and sometimes simultaneously. The purpose of this essay, therefore, is to examine these complex social and religious responses to the tragedy, focusing on the Christian bereaved families’ struggle to make sense of their faith in the face of their unspeakable suffering

Roll-to-roll gravure-printed flexible perovskite solar cells using eco-friendly antisolvent bathing with wide processing window

Driven by recent improvement in efficiency and stability of perovskite solar cells, the next step toward commercialisation is upscaling. Here, the authors demonstrate pilot-scale fully roll-to-roll manufacturing of flexible perovskite solar cells through gravure-printing and antisolvent bathing

Record-efficiency flexible perovskite solar cell and module enabled by a porous-planar structure as an electron transport layer

A facile and low-temperature process to prepare planar perovskite solar cells (PSCs) has led to considerable progress in flexible solar cells toward high throughput production based on a roll-to-roll process. However, the performance of planar PSCs is still lower than that of mesoscopic PSCs using a high temperature process. Here, we report a new concept of a low temperature processed porous planar electron transport layer (ETL) inspired by a mesoporous structure for improving the performance of flexible devices. The structurally and energetically designed porous planar ETL induced the formation of a high quality perovskite and a preferred band alignment, resulting in improved charge collection efficiency in a fabricated device. Through the porous planar ETL, we achieved a power conversion efficiency (PCE) of 20.7% with a certified efficiency of 19.9% on a flexible substrate, which is the highest PCE reported to date. In addition, for the first time, we succeed in fabricating a large area flexible module with the porous planar ETL, demonstrating a PCE of 15.5%, 12.9% and 11.8% on an aperture area of 100 cm(2), 225 cm(2) and 400 cm(2), respectively. We believe that this strategy will pave a new way for realizing highly efficient flexible PSCs

Small-Molecule Organic Photovoltaic Modules Fabricated via Halogen-Free Solvent System with Roll-to-Roll Compatible Scalable Printing Method

For the first time, the photovoltaic modules composed of small molecule were successfully fabricated by using roll-to-roll compatible printing techniques. In this study, blend films of small molecules, BTR and PC₇₁BM were slot-die coated using a halogen-free solvent system. As a result, high efficiencies of 7.46% and 6.56% were achieved from time-consuming solvent vapor annealing (SVA) treatment and roll-to-roll compatible solvent additive approaches, respectively. After successful verification of our roll-to-roll compatible method on small-area devices, we further fabricated large-area photovoltaic modules with a total active area of 10 cm², achieving a power conversion efficiency (PCE) of 4.83%. This demonstration of large-area photovoltaic modules through roll-to-roll compatible printing methods, even based on a halogen-free solvent, suggests the great potential for the industrial-scale production of organic solar cells (OSCs)

One-Step Printable Perovskite Films Fabricated under Ambient Conditions for Efficient and Reproducible Solar Cells

Despite the potential of roll-to-roll processing for the fabrication of perovskite films, the realization of highly efficient and reproducible perovskite solar cells (PeSCs) through continuous coating techniques and low-temperature processing is still challenging. Here, we demonstrate that efficient and reliable CH₃­NH₃­PbI₃ (MAPbI₃) films fabricated by a printing process can be achieved through synergetic effects of binary processing additives, <i>N</i>-cyclo­hexyl-2-pyrroli­done (CHP) and dimethyl sulfoxide (DMSO). Notably, these perovskite films are deposited from premixed perovskite solutions for facile one-step processing under a room-temperature and ambient atmosphere. The CHP molecules result in the uniform and homogeneous perovskite films even in the one-step slot-die system, which originate from the high boiling point and low vapor pressure of CHP. Meanwhile, the DMSO molecules facilitate the growth of perovskite grains by forming intermediate states with the perovskite precursor molecules. Consequently, fully printed PeSC based on the binary additive system exhibits a high PCE of 12.56% with a high reproducibility

Slot-Die Coated Perovskite Films Using Mixed Lead Precursors for Highly Reproducible and Large-Area Solar Cells

Recently, many kinds of printing processes have been studied to fabricate perovskite solar cells (PeSCs) for mass production. Among them, slot-die coating is a promising candidate for roll-to-roll processing because of high-throughput, easy module patterning, and a premetered coating system. In this work, we employed mixed lead precursors consisting of PbAc₂ and PbCl₂ to fabricate PeSCs via slot-die coating. We observed that slot-die-coated perovskite films based on the mixed lead precursors exhibited well-grown and uniform morphology, which was hard to achieve by using only a single lead source. Consequently, PeSCs made with this precursor system showed improved device performance and reproducibility over single PbAc₂. Lastly, a large-area module with an active area of 10 cm² was fabricated with a power conversion efficiency of 8.3%