Review
Polymer Science
Shunsuke Yamamoto
Summary: This article provides a summary of recent advancements in organic neuromorphic devices, with a focus on resistive switches (memristors) and organic electrochemical transistors. The article highlights the materials used in the active layers and device architectures, emphasizing the advantages of organic devices such as flexibility, biocompatibility, and easy fabrication processes.
POLYMER INTERNATIONAL
(2023)
Article
Chemistry, Multidisciplinary
Heejung Roh, Shuwen Yue, Hang Hu, Ke Chen, Heather J. Kulik, Aristide Gumyusenge
Summary: Due to its low-power, fast and highly adaptive operability, as well as scalability, electrochemical random-access memory (ECRAM) technology shows great potential for neuromorphic computing based on artificial neural networks. However, there are still challenges in practical implementation, such as high write noise, asymmetric weight updates, and limited dynamic range. In this study, high-performance, single-transistor and neuromorphic devices based on electrochromic polymers (ECPs) are demonstrated, offering a promising approach for the discovery and design of novel polymer materials for organic ECRAMs.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Jinran Yu, Yifei Wang, Shanshan Qin, Guoyun Gao, Chong Xu, Zhong Lin Wang, Qijun Sun
Summary: This review discusses the development and applications of bioinspired interactive neuromorphic devices. By integrating various sensors and synaptic devices, these devices can sense, store, and process information from the external environment and perform functions of perception, learning, memory, and computation. The article presents the basic model and performance metrics of these devices and discusses the recent progress in materials, device architectures, synaptic plasticity, and potential applications. It also proposes devices that can fuse multiple sensing signals to address more complex problems. Finally, the pros and cons of computing neurons and integrating sensory neurons are discussed, along with the perspectives on future development at the material, device, network, and system levels.
Review
Automation & Control Systems
Yongli He, Li Zhu, Ying Zhu, Chunsheng Chen, Shanshan Jiang, Rui Liu, Yi Shi, Qing Wan
Summary: Neuromorphic computation, inspired by the human brain, has attracted increasing research interest, leading to rapid development of transistor-based neuromorphic devices. These devices have made significant progress in operation principles and latest advancements.
ADVANCED INTELLIGENT SYSTEMS
(2021)
Article
Chemistry, Multidisciplinary
Matteo Cucchi, Daniela Parker, Eleni Stavrinidou, Paschalis Gkoupidenis, Hans Kleemann
Summary: Next-generation implantable computational devices require stable electronic components that can operate in and interact with electrolytic environments without damage. Organic electrochemical transistors (OECTs) have emerged as suitable options, but achieving integrated circuits (ICs) with OECTs in common electrolytes is difficult due to device interactions. Recent studies have focused on minimizing or harnessing crosstalk in order to overcome this challenge. This article discusses the main challenges, trends, and opportunities for realizing OECT-based circuitry in liquid environments, and analyzes successful approaches in autonomous bioelectronics and information processing, demonstrating the potential of using mixed ionic-electronic conductors (OMIECs) for complex computation and machine learning in liquid.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Analytical
Heebum Kang, Jongseon Seo, Hyejin Kim, Hyun Wook Kim, Eun Ryeong Hong, Nayeon Kim, Daeseok Lee, Jiyong Woo
Summary: This study reviews recent advances in ECRAM technology from the material and device engineering perspectives to enhance computing efficiency in a neuromorphic architecture. ECRAM, driven by electric-field-driven ion motion through various electrolytes, enables analog modulation of conductivity, resulting in a linear and symmetric response. The study also discusses the prospects and challenges of ECRAM devices categorized by mobile ion species, as controllable mobile ions play a crucial role in achieving synaptic behavior.
Article
Chemistry, Physical
Yujie Peng, Lin Gao, Changjian Liu, Jinyi Deng, Miao Xie, Libing Bai, Gang Wang, Yuhua Cheng, Wei Huang, Junsheng Yu
Summary: This work demonstrates stretchable synaptic OECTs using a three-dimensional P3HT/SEBS blend porous elastic film which can fully emulate biological synaptic behaviors. The architecture allows for adjustable OECT output and hysteresis, enabling plasticity transition. The stretchable synaptic OECTs exhibit excellent mechanical robustness at a 30% strain and reliable electrical characteristics after 500 stretching cycles. Furthermore, near-ideal weight updates, symmetric long-term potentiation and depression, and image simulation applications are validated.
Review
Chemistry, Multidisciplinary
Geonyeop Lee, Ji-Hwan Baek, Fan Ren, Stephen J. Pearton, Gwan-Hyoung Lee, Jihyun Kim
Summary: Neuromorphic systems, which mimic neural functionalities of a human brain using artificial synapses and neurons, have advantages of high energy efficiency and fast computing speed. 2D materials, with unique surface properties and excellent crystallinity, have emerged as promising candidates for neuromorphic computing hardware due to uncontrollable defects in bulk material-based devices.
Review
Chemistry, Multidisciplinary
Qing Zhang, Tengyu Jin, Xin Ye, Dechao Geng, Wei Chen, Wenping Hu
Summary: Photonic artificial synapses-based neuromorphic computing systems are promising candidates for replacing von Neumann-based systems. Organic field-effect transistors (OFETs) have significant advantages in synaptic emulation, enabling complex photoelectric modulation and simulation of the visual system.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Yanxi Zhang, Gang Ye, Tom P. A. van der Pol, Jingjing Dong, Eveline R. W. van Doremaele, Imke Krauhausen, Yuru Liu, Paschalis Gkoupidenis, Giuseppe Portale, Jun Song, Ryan C. Chiechi, Yoeri van de Burgt
Summary: Organic electrochemical transistors (OECTs) are widely used in low power circuits, biosensors, and neuromorphic computing. However, the choice of high-performance n-type polymers for OECTs is limited. This study reports on three non-fused, planar polymer materials with increasing polar side chains, which improve the OECT performance. The research demonstrates that the performance of OECTs increases with the number of polar side chains, resulting in higher hydrophilicity and electron affinities.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Review
Neurosciences
Mingyue Zeng, Yongli He, Chenxi Zhang, Qing Wan
Summary: Neuromorphic devices with bionic sensory and perceptual functions have great potential in personal healthcare monitoring, neuroprosthetics, and human-machine interfaces. Efforts have been made to incorporate bio-inspired sensing and neuromorphic engineering in the booming artificial intelligence industry. Challenges and opportunities in these fields are being discussed as the emulation of biological sensing and perception systems progresses.
FRONTIERS IN NEUROSCIENCE
(2021)
Article
Chemistry, Multidisciplinary
Sol-Kyu Lee, Young Woon Cho, Jong-Sung Lee, Young-Ran Jung, Seung-Hyun Oh, Jeong-Yun Sun, SangBum Kim, Young-Chang Joo
Summary: Organic neuromorphic computing and sensing platforms utilizing nanofiber channels and self-formed ion-blocking layer in organic electrochemical transistors (OECTs) demonstrate low switching energy and wide bandwidth, providing a new paradigm for energy-efficient neuromorphic computing and sensing in a biological environment without the leakage of personal information.
Article
Chemistry, Multidisciplinary
Mrinal K. Hota, Suman Chandra, Yongjiu Lei, Xiangming Xu, Mohamed N. Hedhili, Abdul-Hamid Emwas, Osama Shekhah, Mohamed Eddaoudi, Husam N. Alshareef
Summary: Covalent organic framework (COF) thin films have been successfully utilized as channel materials in electrical double-layer (EDL) electrochemical transistors, exhibiting similar dynamic behavior to biological synapses.
ADVANCED FUNCTIONAL MATERIALS
(2022)
Article
Nanoscience & Nanotechnology
Pu Guo, Junyao Zhang, Dapeng Liu, Ruizhi Wang, Li Li, Li Tian, Jia Huang
Summary: This study develops solution-processed optoelectronic synaptic transistors (OSTs) that can simulate the visual nociceptor perception functions of the peripheral nervous system (PNS) and the memorizing and computing functions of the central nervous system (CNS). The OSTs demonstrate ultraviolet light selectivity and achieve 1000 conductance states, showing their potential for artificial vision and pattern recognition based on neural networks.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Nanoscience & Nanotechnology
Shunsuke Yamamoto, Anastasios G. Polyravas, Sanggil Han, George G. Malliaras
Summary: This study examines the factors controlling the neuromorphic response of organic electrochemical transistors (OECTs) and highlights the dependence of post-synaptic response timescale on the size of ions in the electrolyte. Modeling further reveals that the transient response of the ionic circuit of the OECT controls the neuromorphic response. These findings provide insights for a more rational design of OECT-based neuromorphic devices.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Materials Science, Multidisciplinary
Wonseop Hwang, Juhee Kim, Seongjin Park, Tae-Hyung Kang, Sunho Kim, Kijung Lee, Myoung-Gyu Lee, Rhokyun Kwak, In-Suk Choi, Hyunjung Yi
Summary: This article reports a simple strategy to achieve a versatile hybrid E-skin patch with great skin comfort. By developing a breathable and stretchable metastructure, the non-stretchable or stiff components and devices are integrated and tethered to the skin, ensuring both breathability and mechanical comfort. A wireless skin sensor system is also developed to enable event-driven wireless monitoring of ECG signals.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Materials Science, Multidisciplinary
Won Seok Cho, Dae Myung Hong, Wan Jae Dong, Tae Hyung Lee, Chul Jong Yoo, Donghwa Lee, Ho Won Jang, Jong-Lam Lee
Summary: In this study, bismuth-based catalysts were introduced for the efficient electrochemical reduction of CO2 to formic acid. The catalysts consisted of petal-shaped Bi2O2CO3 (BOC), which spontaneously formed from Bi thin film in aqueous carbonate solution at room temperature. The BOC petals transformed to reduced BOC (R-BOC) during the electrochemical reduction process, and the lattice mismatch between the domains induced strain at the interfaces. The R-BOC petals exhibited a superior Faradaic efficiency of 95.9% for the electrochemical conversion of CO2 to formic acid.
ENERGY & ENVIRONMENTAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
In Hyuk Im, Seung Ju Kim, Ji Hyun Baek, Kyung Ju Kwak, Tae Hyung Lee, Jin Wook Yang, Da Eun Lee, Jae Young Kim, Hee Ryeong Kwon, Do Yeon Heo, Soo Young Kim, Ho Won Jang
Summary: This study proposes an efficient methodology to integrate halide perovskites as functional materials for memristive crossbar arrays. By controlling the doping concentration of Ag in MAPbI(3), the resistance change characteristics can be tailored. The results show that MAPbI(3) with different Ag contents can achieve different threshold and resistive switching characteristics. Finally, by coupling these switches into 1S-1R integrated components, a larger crossbar array size is achieved.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Kwang-Hun Choi, Soo Jin Kim, Hyoungjun Kim, Ho Won Jang, Hyunjung Yi, Min-Chul Park, Changsoon Choi, Hyunsu Ju, Jung Ah Lim
Summary: In this study, a fibriform electrochemical diode with rectifying, complementary logic, and device protection functions was fabricated for future e-textile circuit systems. The diode was made by twisting metal/polymer semiconductor/ion gel coaxial microfibers and conducting microfiber electrodes. The fibriform diode showed asymmetrical current flow and a rectification ratio of over 102, with retained performance after bending deformations and washings. Full-wave rectifiers and logic gate circuits were implemented by integrating the fibriform diodes, demonstrating AC-to-DC signal conversion and logic operation functions, respectively. The proposed fibriform diode also provided protection for low-voltage operational wearable e-textile circuits by suppressing transient voltages.
Article
Engineering, Environmental
Jeong Hyun Oh, Gyeong Ho Han, Junhyeong Kim, Ji Eun Lee, Hyeonjin Kim, Su Kyung Kang, Hyunki Kim, Sanghyuk Wooh, Pyung Soo Lee, Ho Won Jang, Soo Young Kim, Sang Hyun Ahn
Summary: The rational design of electrodes is crucial for efficient hydrogen production through water electrolysis. This study demonstrates the significant role of physical properties of electrodes in enhancing the mass transfer performance of the electrolyzer, especially at high current densities. Self-supported NiMo and NiFe electrodes with high wettability, porosity, and gas permeability are fabricated using electrodeposition. The combination of these electrodes with a membrane electrode assembly in anion exchange membrane water electrolyzer (AEMWE) results in significantly decreased overpotentials, particularly in the high current density region. The AEMWE achieves a current density of 7.5 A/cm2 with a lower heating value efficiency of 50% and shows excellent stability at a current density of 1.00 A/cm2 for 100 hours. These findings highlight the crucial role of rational electrode design in achieving high-performance AEMWE.
CHEMICAL ENGINEERING JOURNAL
(2023)
Review
Energy & Fuels
Yu Li, Yingji Wu, Kouqi Liu, Seyed Ali Delbari, Aejung Kim, Abbas Sabahi Namini, Quyet Van Le, Mohammadreza Shokouhimehr, Changlei Xia, Ho Won Jang, Rajender S. Varma, Rafael Luque
Summary: The demand for sustainable and ecofriendly materials has increased in recent decades. Metal-organic frameworks (MOFs) have attracted significant interest due to their unique chemical and physical properties. They have been utilized in various chemistries to convert biomass into biofuels and other valuable compounds. This review article discusses the conversion of glucose into 5-hydroxymethylfurfural (HMF) or levulinic acid, HMF into 2,5-furandicarboxylic acids, vanillin into 2-methoxy-4-methylphenol, and other transformations using MOF-based catalysts with improved green credentials. The article also examines the reusability aspect, reactivity of the catalysts with MOFs, benefits, and potential drawbacks, as well as future perspectives.
Article
Energy & Fuels
Min Kyung Lee, Sungkyun Choi, Hoonkee Park, Tae Hyung Lee, Sol A. Lee, Jin Wook Yang, Su Geun Ji, Woo Seok Cheon, Sang Hyun Ahn, Soo Young Kim, Mohammadreza Shokouhimehr, Jin Young Kim, Ho Won Jang
Summary: A novel nickel-based 2D MOF was synthesized and demonstrated excellent electrocatalytic performance for the oxygen evolution reaction. The resulting Ni-NDC@NF exhibited low overpotential, small Tafel slope, high faradaic efficiency, and long-term stability. Furthermore, the electrodeposition of NiMo alloy on Ni-NDC@NF enhanced the hydrogen evolution reaction activity, enabling efficient overall water splitting.
Article
Nanoscience & Nanotechnology
Yong-Hee Lee, Byeongjun Gil, Duyoung Yang, Mi-Hyang Sheen, Euijoon Yoon, Yongjo Park, Ho-Won Jang, Sangmoon Yoon, Miyoung Kim, Young-Woon Kim
Summary: This study explores the relationship between atomic arrangement and luminescence properties in a high-quality α-Ga2O3 thin film on an Al2O3 single-crystal membrane. The strain induced by merging domain boundaries shows significant variability in annular darkfield images, despite no confirmed additional gallium concentration. The bandgap energy of α-Ga2O3 is estimated to be 5.56 eV from CL measurement in a transmission electron microscope. A peak at 320 nm is observed within the domain, while the domain boundary exhibits spectrum peaks at 380-480 nm. The formation of anti-phase domains (APD) is caused by the instabilities of Al-O bonding templates provided by the Al2O3 substrate. The APD boundary results in a characteristic wavelength of 350 nm, which arises from the merging boundary of in-phase and anti-phase domains.
Article
Materials Science, Multidisciplinary
Jaehyun Kim, Ho Won Jang
Summary: Water electrolysis has the potential to produce renewable hydrogen fuel at a large scale, replacing fossil fuels and reducing greenhouse gas emissions. Machine learning can accelerate the discovery and design of superior electrocatalysts.
KOREAN JOURNAL OF MATERIALS RESEARCH
(2023)
Article
Nanoscience & Nanotechnology
Young Ju Son, Changjoon Keum, Minsoo Kim, Goeen Jeong, Soyeong Jin, Hae Won Hwang, Hyewon Kim, Kyungwoo Lee, Hojeong Jeon, Hojun Kim, Ki Joo Pahk, Ho Won Jang, Jeong-Yun Sun, Hyung-Seop Han, Kwan Hyi Lee, Myoung-Ryul Ok, Yu-Chan Kim, Youngdo Jeong
Summary: This study designed a nanoscale vibrating surface to control cell behavior through selective repetitive cell deformation. By adjusting the frequency of nanovibration, the selective regulation of cell-cell adhesion was demonstrated.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Physical
Cheon Woo Moon, Nikhil C. Bhoumik, Profulla Mondol, Sung Hyuk Park, Ho Won Jang, Christopher J. Barile
Summary: The control of solar light and heat emission through windows is crucial for increasing building energy efficiency. Reversible Zn electrodeposition has emerged as a promising method for creating electronically tintable dynamic windows. In this study, we observe extraordinary absorption in Zn electrodeposits formed from DMSO electrolytes, which exceeds the predicted absorption based on the Beer-Lambert law for a uniform Zn thin film. The low charge required for electroplating allows for the construction of large-area devices that switch uniformly, and the enhanced absorption is attributed to plasmonic effects among Zn nanoparticles and ZnO dendrites in the film. Through this research, design principles are provided for constructing low-charge and high-contrast dynamic windows based on metal and metal oxide.
Review
Chemistry, Applied
Sang Eon Jun, Sungkyun Choi, Jaehyun Kim, Ki Chang Kwon, Sun Hwa Park, Ho Won Jang
Summary: This review article summarizes the characteristics of non-noble metal single atom catalysts (NNMSACs), including tuning reaction selectivity, metal-support interaction, and catalytic active center. It also introduces representative NNMSACs (Co, Ni, Fe, Cu, and dual metal SACs) for various electrocatalytic reactions. The remaining challenges for further advances of NNMSACs in geometric, electronic, and electrochemical properties are discussed.
CHINESE JOURNAL OF CATALYSIS
(2023)
Article
Chemistry, Physical
Sungkyun Choi, Sol A. Lee, Jin Wook Yang, Woonbae Sohn, Jaehyun Kim, Woo Seok Cheon, Jaemin Park, Jin Hyuk Cho, Chung Won Lee, Sang Eon Jun, Sung Hyuk Park, Jooho Moon, Soo Young Kim, Ho Won Jang
Summary: Designing an appropriate catalyst for photoelectrochemical water splitting is crucial for efficient solar to hydrogen energy production. Introducing small amounts of noble metals, such as Au, into transition metal-based materials can enhance the efficiency of solar water oxidation.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Chemistry, Analytical
Tae Hoon Eom, Sang Eun Lee, Yeong Jae Kim, Sungkyun Choi, Gi Baek Nam, Jung-El Ryu, Tae Hyung Lee, Jin Wook Yang, Sung Hwan Cho, Seung Ju Kim, Sang Eon Jun, Seonyong Lee, Seungsoo Kim, Hee Jung Park, Ho Won Jang
Summary: Chemoresistive humidity sensors based on ultrathin V2O5•nH2O nanobelts show promising performance in real-time breath monitoring, with rapid response and recovery, as well as excellent selectivity to humidity.
SENSORS AND ACTUATORS B-CHEMICAL
(2024)