Article
Green & Sustainable Science & Technology
Muheeb Ahmad Alkhalayfeh, Azlan Abdul Aziz, Mohd Zamir Pakhuruddin
Summary: The review discusses the use of plasmonic effect to enhance the power conversion efficiency of thin-film polymer or organic solar cells by embedding metal nanoparticles for improved light absorption and charge carrier transport. The position, size, and shape of nanoparticles play a crucial role in significantly improving the efficiency of diverse geometries and design approaches.
RENEWABLE & SUSTAINABLE ENERGY REVIEWS
(2021)
Article
Energy & Fuels
Kai Cheong Tam, Hirotoshi Saito, Philipp Maisch, Karen Forberich, Sarmad Feroze, Yutaka Hisaeda, Christoph J. Brabec, Hans-Joachim Egelhaaf
Summary: This research addresses the performance gap between commercially available organic photovoltaic modules and hero cells in literature by developing a printable silver nanoparticle film top electrode. The AgNP electrode achieves almost the same power conversion efficiencies as evaporated silver electrodes and performs even better under low light conditions. This work demonstrates that fully printed OPV modules can achieve similar performance as small scale OPV cells with evaporated electrodes, offering an attractive alternative for large scale manufacturing.
Article
Chemistry, Analytical
Vivek Semwal, Oliver Rishoj Jensen, Ole Bang, Jakob Janting
Summary: This paper presents numerical and experimental results on the effects of spherical gold nanoparticles (AuNPs) size on Localized Surface Plasmon Resonance (LSPR) refractive index (RI) sensitivity, Figure of Merit (FoM), and penetration depth (dp). The study also investigates the influence of AuNP dimer interparticle distance (ds) on these parameters. The results show that a diameter of 60 nm AuNPs provides the best FoM. Furthermore, the interparticle distance between d = 20 nm and 60 nm AuNPs significantly affects the RI sensitivity. The importance of penetration depth information for biosensing using aptamers is discussed in relation to aptamer size.
Article
Chemistry, Physical
Jinqiu Xu, Francis Lin, Lei Zhu, Ming Zhang, Tianyu Hao, Guanqing Zhou, Ke Gao, Yecheng Zou, Gang Wei, Yuanping Yi, Alex K. Y. Jen, Yongming Zhang, Feng Liu
Summary: This research investigates the structure features and intermolecular interactions of nonfullerene acceptors (NFAs) in single crystal and thin films, as well as their solar cell applications. Key parameters and intermolecular forces that lead to different crystalline packing motifs are identified. Atomic modification induces hydrogen bonding or pi-pi stacking column, resulting in different crystalline packing. Molecular assembly in thin films is initiated by hydrogen bonding and completed by pi-pi stacking reorganization. The crystalline packing motif is not directly related to device efficiency, but the crystalline morphology influences exciton/carrier dynamics and device performance. A broader understanding of the scaling behavior of organic semiconductor crystals ranging from oligoacenes to NFAs is established.
ADVANCED ENERGY MATERIALS
(2022)
Article
Physics, Applied
Kohei Shimanoe, Soshi Endo, Tetsuya Matsuyama, Kenji Wada, Koichi Okamoto
Summary: Metal nanovoid (NV) and metal on metal nano-hemisphere (MoNH) structures are introduced to tune the localized surface plasmon resonance (LSPR) for wider wavelength ranges. These structures enable flexible tuning of the LSPR in the UV and NIR wavelength regions, respectively, and are fabricated via thermal annealing of deposited metal thin films. Both experimentally and numerically verified, these structures provide effective means of adjusting LSPR.
APPLIED PHYSICS EXPRESS
(2021)
Review
Energy & Fuels
Nora Schopp, Viktor V. Brus
Summary: This review summarizes the current state of materials science and device physics of semitransparent organic solar cells. It outlines synthetic strategies to narrow the band gap of organic semiconducting molecules and discusses recent developments in polymer donor and near-infrared absorbing acceptor materials. The review provides an overview of transparent electrodes and emphasizes the importance of in-depth understanding of the device physics of ST-OPVs.
Article
Chemistry, Multidisciplinary
Jeannine Gruene, Giacomo Londi, Alexander J. Gillett, Basil Staehly, Sebastian Lulei, Maria Kotova, Yoann Olivier, Vladimir Dyakonov, Andreas Sperlich
Summary: The development of non-fullerene acceptors (NFAs) in organic photovoltaics (OPV) has led to a significant progress in power conversion efficiencies, reaching nearly 20%. However, triplet states have been found to negatively affect device performance, leading to non-radiative losses and device degradation. A study using various spin-sensitive methods and quantum-chemical calculations identified the presence of triplet excitons in OPV blends, providing insights into the pathways for triplet formation and suggesting potential for improved charge generation to enhance OPV efficiencies.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Nora Schopp, Gulnur Akhtanova, Patchareepond Panoy, Alexandr Arbuz, Sangmin Chae, Ahra Yi, Hyo Jung Kim, Vinich Promarak, Thuc-Quyen Nguyen, Viktor V. Brus
Summary: This study investigates the charge generation-recombination dynamics in three narrow-bandgap near-IR absorbing nonfullerene-based organic photovoltaic systems. The results show that diluting the polymer donor with visible-range absorption leads to highly transparent active layers, and the optimized device configuration achieves high photoconversion efficiencies.
ADVANCED MATERIALS
(2022)
Review
Environmental Sciences
Mary Rosana Nalzala Thomas, Vincent Joseph Kanniyambatti Lourdusamy, Aparna Annamalai Dhandayuthapani, Vijayalakshmi Jayakumar
Summary: The emergence of novel technologies has led to the necessity for environmental and economic integration, with a focus on energy consumption. Renewable resources like solar and wind energy are being opted for to meet future needs, with dye-sensitized solar cells considered as a better alternative due to their ability to function under various conditions.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Chemistry, Physical
Min Xi, Longchang Xu, Nian Li, Shudong Zhang, Zhenyang Wang
Summary: Copper sulfide nanostructures, particularly hollow nanocages, demonstrate excellent solar photothermal performance with higher conversion efficiency compared to solid nanospheres.
Article
Nanoscience & Nanotechnology
Derek de Jong, Julian Karst, Dominik Ludescher, Moritz Floess, Sophia Moell, Klaus Dirnberger, Mario Hentschel, Sabine Ludwigs, Paul V. Braun, Harald Giessen
Summary: We propose an electrically switchable, compact metasurface device based on PEDOT:PSS and a gel polymer electrolyte. By applying square-wave voltages, the PEDOT:PSS can be reversible switched from dielectric to metallic state. We demonstrate a compact standalone metadevice that allows for electrically controlled tuning of plasmonic resonances and beam switching. Our work paves the way for solid-state switchable metasurfaces and switchable holographic devices.
Article
Chemistry, Physical
Moritz Riede, Donato Spoltore, Karl Leo
Summary: Organic solar cells have the potential to be the cheapest form of electricity, surpassing silicon photovoltaics. However, challenges remain in increasing efficiency and long-term stability. The technology could be used in building integrated photovoltaics and portable electronics, with the potential to have the lowest carbon footprint of all energy generation technologies.
ADVANCED ENERGY MATERIALS
(2021)
Article
Green & Sustainable Science & Technology
Caiyan Qin, Qunzhi Zhu, Xiaoke Li, Chunlei Sun, Meijie Chen, Xiaohu Wu
Summary: In this study, slotted metallic nanospheres were proposed for solar thermal conversion. By exciting electric and magnetic resonances, these nanospheres can absorb solar energy across a broad spectrum and reduce scattering, leading to improved absorption efficiency. The study also showed that the optical properties of the nanospheres can be effectively controlled by adjusting the particle size and number of slots.
Article
Energy & Fuels
Marcelo de P. Boucanova, Caio V. P. Vital, Diego Rativa, Luis A. Gomez-Malagon
Summary: This study explores the use of silver, gold, and copper nanofluids to enhance the performance of a single slope solar distiller, synthesizing the nanofluids with chemical methods, resulting in increased water production and improved thermal efficiency.
Review
Optics
Jason A. Rohr, B. Edward Sartor, Jason Lipton, Andre D. Taylor
Summary: Our oceans are vast and difficult to monitor, but a fully autonomous 'Internet of Underwater Things' powered by underwater solar energy could revolutionize data collection. However, traditional silicon solar cells do not perform well underwater, so alternative materials like GaInP variants, CdTe, organic semiconductors, and perovskite semiconductors need to be explored. Challenges such as antifouling coatings and new certification standards must also be addressed.
Article
Chemistry, Physical
Byeong Guk Jeong, Jun Hyuk Chang, Donghyo Hahm, Seunghyun Rhee, Myeongjin Park, Sooho Lee, Youngdu Kim, Doyoon Shin, Jeong Woo Park, Changhee Lee, Doh C. Lee, Kyoungwon Park, Euyheon Hwang, Wan Ki Bae
Summary: This study presents an approach to control the potential profile of III-V-II-VI h-NCs by steering dipole densities at the interface, allowing for control of the optical and electrical characteristics of these heterostructured nanocrystals. The synthesis of h-NCs with atomic precision enables correlation of interfacial dipole moments with the crystals' photochemical stability and optoelectronic performance. Controlled synthesis of heterostructured III-V-II-VI nanocrystals demonstrates that dipole moments formed at the core-shell interface can tune the optoelectronic properties of these nanomaterials and their performance in light-emitting devices.
Article
Nanoscience & Nanotechnology
Jung Bae Son, Jooyoun Kang, Sohyeon Bae, Key Young Yang, Jongseok Han, Kyung Suk Min, Changhee Lee, Soohwan Sul, Seong Keun Kim
Summary: The irreversible loss of emission intensity in organic light-emitting diode (OLED) devices after extended operation is a significant issue in OLED technology and industry. A new method for in situ, layer-specific analysis of OLED devices demonstrates the predominant role of bleaching in influencing OLED performance.
Article
Nanoscience & Nanotechnology
Xianji Piao, Jonghwa Shin, Namkyoo Park
Summary: The intrinsic geometry of wavevector diagrams plays a critical role in electronic or photonic transport. The study investigates the Lifshitz transition and its impact on abnormal transport. By developing a spatial analogy and analyzing the dimensionality and gaps of wavevector diagrams, the authors reveal unique features in transverse-spin modes.
Article
Engineering, Electrical & Electronic
Myoungjin Park, Young Il Kim, Yun Ku Jung, Jin-goo Kang, Sehun Kim, Jaekook Ha, Yeo-geon Yoon, Changhee Lee
Summary: Electroluminescence quantum dot devices (QD-LEDs) hold great promise for future display technology, particularly the top emission device structure which allows for high aperture ratio full color displays. This study successfully demonstrates the fabrication of all inkjet-printed Cd-free active matrix QD-LED devices, overcoming the challenges of the inkjet printing process. Factors influencing QD efficiency and printing, as well as the impact of ETL solvent on QD, were investigated. The inkjet-printed QD-LED devices achieved high current efficiencies, marking an important step towards the practical application of Cd-free QD-LED displays.
JOURNAL OF THE SOCIETY FOR INFORMATION DISPLAY
(2022)
Article
Materials Science, Multidisciplinary
Jungmin Kim, Seungkyun Park, Sunkyu Yu, Namkyoo Park
Summary: This paper proposes the use of deep neural networks to engineer active disorder-disordered structures, aiming to resolve the spatial and temporal complexities in wave-matter interactions. The results show that through inverse design and evaluation of active disorder, it is possible to achieve disordered structures with target wave responses and reveal the functional disorder of light.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Xianji Piao, Namkyoo Park
Summary: In this study, we demonstrate the existence of delocalization behaviors induced by non-Hermitian disorder in two-dimensional systems, as opposed to the typical disorder-induced localization. By controlling the contrast between material phases, we show a dramatic change in the relationship between localization and disorder, even exhibiting a disorder-induced delocalization in the low-contrast regime. This counterintuitive phenomenon originates from the disorder-induced clustering of non-Hermitian material phases, which leads to the unbroken condition of parity-time symmetry.
Article
Multidisciplinary Sciences
Mihyang Sheen, Yunhyuk Ko, Dong-uk Kim, Jongil Kim, Jin-ho Byun, YongSeok Choi, Jonghoon Ha, Ki Young Yeon, Dohyung Kim, Jungwoon Jung, Jinyoung Choi, Ran Kim, Jewon Yoo, Inpyo Kim, Chanwoo Joo, Nami Hong, Joohee Lee, Sang Ho Jeon, Sang Ho Oh, Jaekwang Lee, Nari Ahn, Changhee Lee
Summary: In this study, a blue nanorod LED with high external quantum efficiency (EQE) was demonstrated by reducing the size-dependent efficiency reduction through passivation. This work paves the way for manufacturing self-emissive nanorod LED displays for next-generation display technologies.
Article
Optics
Seunghwa Oh, Jungmin Kim, Xianji Piao, Seulong Kim, Kihong Kim, Sunkyu Yu, Namkyoo Park
Summary: The effect of deep subwavelength disorder in one-dimensional dichromic multilayer films on optical transmission, localization length, and the Goos-Fanchen shift around the critical angle is analyzed. The study emphasizes the role of deep subwavelength structures in disorder-induced transmission enhancement and suggests the inverse design of such structures for targeted order metrics or abnormal optical responses.
Article
Materials Science, Multidisciplinary
Chi Hyun Ryoo, Jongseok Han, Jung-hoon Yang, Kwangmo Yang, Illhun Cho, Seyoung Jung, Sehun Kim, Hyein Jeong, Changhee Lee, Ji Eon Kwon, Illia E. Serdiuk, Soo Young Park
Summary: By introducing substituent groups, efficient blue TADF materials can be developed, exhibiting high external quantum efficiency in OLEDs.
ADVANCED OPTICAL MATERIALS
(2022)
Article
Multidisciplinary Sciences
Jagang Park, Hyukjoon Cho, Seojoo Lee, Kyungmin Lee, Kanghee Lee, Hee Chul Park, Jung -Wan Ryu, Namkyoo Park, Sanggeun Jeon, Bumki Min
Summary: In this study, the unique Bloch-Floquet and non-Bloch band structures of a photonic Floquet medium are experimentally revealed in the microwave regime, with a one-dimensional array of time -periodically driven resonators. These non-Hermitian band structures are shown to be two measurable distinct subsets of complex eigenfrequency surfaces of the photonic Floquet medium defined in complex momentum space.
Article
Engineering, Electrical & Electronic
Sadia Sayed Urmi, Mohammad Masum Billah, Sunaina Priyadarshi, Jinbaek Bae, Byunglib Jung, Suhui Lee, Keunwoo Kim, Jiyeong Shin, Sangun Choi, Junhyung Lim, Taewook Kang, Changhee Lee, Jin Jang
Summary: We present a novel active split structure of low-temperature polysilicon (LTPS) thin film transistor (TFT) on polyimide (PI) substrate, which exhibits robust electrical performance under mechanical strain. Compressive and tensile bending tests were conducted with cylinders of radii 3, 2, and 1 mm, respectively. Compared to the conventional TFT, the active split TFT shows much more stable electrical performance. The conventional LTPS TFT experiences electrical failure when subjected to tensile or compressive bending with a 1 mm radius cylinder, while the split poly-Si islands in the active split TFT resist crack formation/propagation, resulting in robust electrical performance.
IEEE ELECTRON DEVICE LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Jaehoon Kim, Jeongkyun Roh, Myoungjin Park, Changhee Lee
Summary: Colloidal quantum dots (QDs) have great potential in display technologies due to their unique optical properties. Significant improvements have been achieved in quantum dot light-emitting diodes (QLEDs) in the past decade, primarily through the development of high-quality QDs and optimized device architectures. This review provides insights into the current status and development direction of QLEDs, guiding the way towards their commercialization.
ADVANCED MATERIALS
(2023)
Article
Physics, Multidisciplinary
Jungmin Kim, Dayeong Lee, Sunkyu Yu, Namkyoo Park
Summary: Photonic systems can utilize time as an alternative to space, eliminating the need for spatial patterning. Recent studies have shown the importance of temporal degree of freedom in photonics and its analogy with spatial axes. In this research, we investigate the design of photonic time disorder to achieve optical functionalities without spatial patterning.
Article
Physics, Multidisciplinary
Xinhua Wen, Heung Kit Yip, Choonlae Cho, Jensen Li, Namkyoo Park
Summary: We propose a concept called acoustic amplifying diode that combines signal isolation and amplification in a single device. The signal is exponentially amplified in one direction with no reflection and perfectly absorbed in another direction. By using impedance matching, the device eliminates reflection in both directions and prevents backscattering to the signal source. We demonstrate the amplifying diode using an active metamaterial with nonreciprocal Willis coupling, and discuss the flexibility of implementation with the presence of both reciprocal and nonreciprocal couplings.
PHYSICAL REVIEW LETTERS
(2023)
Article
Multidisciplinary Sciences
Sunkyu Yu, Namkyoo Park
Summary: The authors simulated programmable photonic circuits targeting universal unitaries and found a heavy-tailed distribution of a type of unit rotation operator. They suggested hardware pruning for random unitaries and provided design strategies for high fidelity and energy efficiency in large-scale quantum computations and photonic deep learning accelerators. Developing hardware for high-dimensional unitary operators plays a vital role in implementing quantum computations and deep learning accelerations.
NATURE COMMUNICATIONS
(2023)