Article
Nanoscience & Nanotechnology
Young Geun Song, Ji Eun Kim, Jae Uk Kwon, Suk Yeop Chun, Keunho Soh, Sahn Nahm, Chong-Yun Kang, Jung Ho Yoon
Summary: A highly reliable threshold switching device, based on Ag and SiO2 nanorods, that is immune to atmospheric changes has been developed. This device exhibits switching characteristics that are electroforming-free, repeatable, consistent, and resistant to changes in ambient conditions and compliance levels during operation.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Geunyoung Kim, Younghyun Lee, Jae Bum Jeon, Woon Hyung Cheong, Woojoon Park, Hanchan Song, Kyung Min Kim
Summary: A threshold-modulative artificial GABAergic nociceptor is proposed for the first time, showing potential applications in advanced sensory devices by implementing hot- and cold-sensitive thermoreceptors.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Rohit Abraham John, Natalia Yantara, Si En Ng, Muhammad Iszaki Bin Patdillah, Mohit Rameshchandra Kulkarni, Nur Fadilah Jamaludin, Joydeep Basu, Ankit, Subodh G. Mhaisalkar, Arindam Basu, Nripan Mathews
Summary: The focus of current research is on neuromorphic computing hardware, particularly on the efficient implementation of drift and diffusive memristors for deep learning and reservoir computing networks. While organic ionotronic electrochemical materials offer an alternative, the development of diffusive memristors with these materials is still in early stages, with the modulation of their switching dynamics yet to be explored.
ADVANCED MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Jia-He Yang, Shi-Cheng Mao, Kuan-Ting Chen, Jen-Sue Chen
Summary: This paper introduces a threshold-switching memristor for artificial neural networks, which mimics multiple biological functions of neurons and overcomes the issues in conventional memristors.
ADVANCED ELECTRONIC MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
Harshada Patil, Honggyun Kim, Kalyani D. Kadam, Shania Rehman, Supriya A. Patil, Jamal Aziz, Tukaram D. Dongale, Zulfqar Ali Sheikh, Mehr Khalid Rahmani, Muhammad Farooq Khan, Deok-kee Kim
Summary: With the advancement of artificial intelligence technology, the development of humanoid robots requires more biomimetic functions, including artificial nociceptors. Organic-inorganic halide perovskites (OHPs) are capable of mimicking biological neurons due to their ion migration properties. In this study, a versatile and reliable OHP-based diffusive memristor was developed as an artificial nociceptor, demonstrating key characteristics such as threshold, no adaptation, relaxation, and sensitization. Furthermore, the feasibility of using OHP nociceptors in artificial intelligence was explored through the creation of a thermoreceptor system, suggesting potential applications in future neuromorphic intelligence platforms.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Ghulam Dastgeer, Haider Abbas, Duk Young Kim, Jonghwa Eom, Changhwan Choi
Summary: A nano-sized two-terminal memristor demonstrating volatile threshold switching has been fabricated to emulate biological synaptic functions in neuromorphic computing. The device exhibits a large I-ON/OFF ratio and the experimental realization of synaptic behavior validates a psychological model of human brain learning. Input pulses with different spike-times are used to replicate synaptic functionalities.
PHYSICA STATUS SOLIDI-RAPID RESEARCH LETTERS
(2021)
Article
Chemistry, Multidisciplinary
Lukas Voelkel, Dennis Braun, Melkamu Belete, Satender Kataria, Thorsten Wahlbrink, Ke Ran, Kevin Kistermann, Joachim Mayer, Stephan Menzel, Alwin Daus, Max C. Lemme
Summary: The switching mechanism of multilayer hexagonal boron nitride (h-BN) threshold memristors with nickel (Ni) electrodes is investigated through temperature-dependent current-voltage measurements. The formation and retraction of nickel filaments along boron defects in the h-BN film are proposed as the resistive switching mechanism. The electrical data are corroborated with TEM analyses, confirming the viability of using temperature-dependent current-voltage measurements as a valuable tool for analyzing resistive switching phenomena in memristors made of 2D materials. The memristors exhibit wide current operation range, low standby currents, low cycle-to-cycle variability, and a large On/Off ratio.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Physics, Applied
Jingyao Bian, Ye Tao, Zhongqiang Wang, Yongjun Dong, Zhuangzhuang Li, Xiaoning Zhao, Ya Lin, Haiyang Xu, Yichun Liu
Summary: A True Random Number Generator (TRNG) system based on the stochastic duration time of double threshold-switching (TS) memristors is proposed. The reliable stochasticity of this system is mainly attributed to the gradual dissolution of Ag conductive channels and the synergistic effect of these two TS memristors. The random data key generated by this system passed the National Institute of Standards and Technology randomness tests.
APPLIED PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Lei Liu, Jie Dong, Jie Liu, Qiu Liang, Yaru Song, Wanhui Li, Shengbin Lei, Wenping Hu
Summary: MOF nanofilms, with their large surface area, high stability, and tunable structure, offer new perspectives in memristor devices. This study presents a facile and effective method for preparing Cu-3(HHTP)(2) nanofilms, which exhibit superior performance in memory devices.
Article
Nanoscience & Nanotechnology
Andrey Sokolov, Mumtaz Ali, Hui Li, Yu-Rim Jeon, Min Jae Ko, Changhwan Choi
Summary: Transition metal carbides, known as MXenes, exhibit unique properties that can be utilized in new electronic devices such as memory storage and electronic synapse applications. These devices demonstrate threshold resistive switching characteristics based on Ag+ migration dynamics, similar to the ion dynamics of a biological synapse, allowing for emulation of various biological synapse functions. This development has the potential to be used in next-generation hardware-based artificial intelligence systems.
ADVANCED ELECTRONIC MATERIALS
(2021)
Article
Nanoscience & Nanotechnology
Solomon Amsalu Chekol, Stephan Menzel, Rainer Waser, Susanne Hoffmann-Eifert
Summary: This study investigates the effect of a series resistor on the switching dynamics of Ag/HfO2/Pt diffusive memristor devices and discusses its implications on device operation.
ADVANCED ELECTRONIC MATERIALS
(2022)
Article
Automation & Control Systems
Kyung Seok Woo, Jaehyun Kim, Janguk Han, Jin Myung Choi, Woohyun Kim, Cheol Seong Hwang
Summary: In this study, a true random number generator based on a CuxTe1-x diffusive memristor using its threshold switching behavior is reported. The TRNG system showed excellent performance in passing all 15 NIST randomness tests without post-processing and even in high-temperature conditions. Additionally, a high-speed TRNG with a nonlinear-feedback shift register was implemented, demonstrating the highest rate among reported volatile-memristor-based TRNGs.
ADVANCED INTELLIGENT SYSTEMS
(2021)
Review
Chemistry, Multidisciplinary
Emanuel Carlos, Rita Branquinho, Rodrigo Martins, Asal Kiazadeh, Elvira Fortunato
Summary: Metal oxide resistive switching memories are crucial for the requirements of the Internet of Things, and solution-based devices offer advantages such as high flexibility and low cost. These devices are emergent and promising non-volatile memories for future electronics.
ADVANCED MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Shimul Kanti Nath, Sanjoy Kumar Nandi, Sujan Kumar Das, Yan Liang, Robert G. Elliman
Summary: Volatile threshold switching and current-controlled negative differential resistance (NDR) in metal-oxide-metal (MOM) devices are influenced by the thermal properties of the device-structure. This study investigates the effect of metal electrodes on the threshold switching response of NbOx-based cross-point devices. The electroforming and switching characteristics are strongly influenced by the thickness and thermal conductivity of the top-electrode, affecting heat loss from the NbOx film.
Article
Materials Science, Multidisciplinary
Juyeong Pyo, Seung-Jin Woo, Kisong Lee, Sungjun Kim
Summary: This work demonstrates the dual nature of threshold switching and non-volatile memory switching in Ag/SnOx/TiN memory devices, with the performance being influenced by different current values. Variations in resistance states at different CC values, as well as the application of pulse operation in volatile switching, set, reset, and negative-set behaviors, were observed during experiments.
Article
Chemistry, Multidisciplinary
Jin Hyuk Cho, Chaehyeon Lee, Sung Hyun Hong, Ho Yeon Jang, Seoin Back, Myung-gi Seo, Minzae Lee, Hyung-Ki Min, Youngheon Choi, Youn Jeong Jang, Sang Hyun Ahn, Ho Won Jang, Soo Young Kim
Summary: This study demonstrates the efficient electrocatalytic conversion of CO2 to CO using zeolite-imidazolate-frameworks-8 (ZIF-8) doped with transition metal ions (Ni, Fe, and Cu). The optimized Cu-doped ZIF-8 showed high partial current density and maximum Faradaic efficiency, with stable catalytic activity. The study also provides insights into the CO2 reduction pathway.
ADVANCED MATERIALS
(2023)
Article
Engineering, Environmental
Jooyoung Kim, Hyunki Kim, Sungjun Kim, Jue-Hyuk Jang, Hyuntae Sohn, Seok Jin Hong, Junhyeong Kim, Gyeong Ho Han, Seonghyun Choe, Yung-Eun Sung, Soo Young Kim, Ho Won Jang, Tae Hwan Jo, Hyung-Kyu Lim, Sung Jong Yoo, Sang Hyun Ahn
Summary: This study presents a simple electrochemical strategy to fabricate atomic Pt clusters on Au dendrites, resulting in a significantly reduced Pt loading. The prepared Pt/Au/CP sample exhibits high selectivity for formic acid oxidation reaction and maintains stable activity even after cycling tests.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Materials Science, Multidisciplinary
Ruiguang Ning, Soo Young Jung, Haneul Choi, Byeong-hyeon Lee, Min-Seok Kim, Hyung-Jin Choi, Jun Young Lee, Jin Soo Park, Sung-Jin Jung, Ho Won Jang, Sung Ok Won, Hye Jung Chang, Ji-Soo Jang, Kyu Hyoung Lee, Byung Chul Lee, Seung-Hyub Baek
Summary: Epitaxial complex oxide heterostructures on Si are an excellent platform for multifunctional electronic devices. This study reports a method for the selective area epitaxial growth of complex oxide heterostructures on Si using a hard mask lift-off technique. By using a water-soluble oxide as a lift-off hard mask, the complex oxide can be grown at high temperatures and oxidizing environments, and subsequently selectively etched away using deionized water.
ELECTRONIC MATERIALS LETTERS
(2023)
Review
Chemistry, Multidisciplinary
Gyeong Ho Han, Junbeom Bang, Gaeun Park, Seonghyun Choe, Youn Jeong Jang, Ho Won Jang, Soo Young Kim, Sang Hyun Ahn
Summary: Environmental problems, including global warming, are major global challenges, and researchers are exploring various methods to reduce CO2 emissions. The CO2 reduction reaction has attracted significant attention due to its potential utilization of renewable energy sources. This reaction converts stable CO2 molecules into valuable hydrocarbon products such as CO, CH4, C2H4, and C2H5OH. The conversion into hydrocarbons above C-2 is crucial for economic benefits. Investigations have shown that Cu-based catalysts play a unique role in the C-C coupling reaction for electrocatalysis. This review provides an overview of the CO2 reduction reaction via electrochemical, photochemical, and photoelectrochemical processes, including the mechanism of hydrocarbon formation and recent advancements.
Article
Multidisciplinary Sciences
Sang Eon Jun, Youn-Hye Kim, Jaehyun Kim, Woo Seok Cheon, Sungkyun Choi, Jinwook Yang, Hoonkee Park, Hyungsoo Lee, Sun Hwa Park, Ki Chang Kwon, Jooho Moon, Soo-Hyun Kim, Ho Won Jang
Summary: This study demonstrates the decoration of iridium single atoms (SAs) on silicon photoanodes, and assesses their role in separating and transferring photogenerated charge carriers. By embedding the iridium SAs in a NiO/Ni thin film, a benchmarking photoelectrochemical performance is achieved with high photocurrent density and stability. This research provides insights into the rational design of SAs on silicon photoelectrodes and the potential of iridium SAs in boosting photogenerated charge carrier kinetics.
NATURE COMMUNICATIONS
(2023)
Review
Chemistry, Physical
Yu Li, Yingji Wu, Seyed Ali Delbari, Aejung Kim, Abbas Sabahi Namini, Quyet Van Le, Changlei Xia, Rafael Luque, Ho Won Jang, Mohammadreza Shokouhimehr, Rajender S. Varma
Summary: The practical benefits of sustainable catalysts have led to an increased demand for extended carbon supported nanocatalysts. These nanocatalysts have high porosity and physiochemical stability, making them useful for converting biomass into valuable chemicals. Carbon nanostructures can be functionalized and adorned with metal nanoparticles to exhibit excellent catalytic activity and endurance. This article exemplifies the significance of using nanostructured carbon catalysts and discusses the benefits and limitations of these catalysts for biomass conversion.
MOLECULAR CATALYSIS
(2023)
Article
Chemistry, Multidisciplinary
In Hyuk Im, Ji Hyun Baek, Seung Ju Kim, Jaehyun Kim, Sung Hyuk Park, Jae Young Kim, J. Joshua Yang, Ho Won Jang
Summary: Utilizing the diffusion threshold switching phenomenon in silver-incorporated halide perovskites, this study demonstrates the functions of afferent neurons and an artificial mechano-nociceptive system. These results represent significant progress in the field of bio-inspired electronics and systems.
ADVANCED MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Yoon Jung Lee, Youngmin Kim, Hyeongyu Gim, Kootak Hong, Ho Won Jang
Summary: This review highlights recent progress in the field of nanoelectronics utilizing metal-insulator transition (MIT) behaviors in Mott insulators. It covers a wide range of topics, from the microscopic interactions in condensed matter systems to the macroscopic device functionalities by various external stimuli. This review serves as an overview and a comprehensive understanding of the design of next-generation MIT-based nanoelectronics.
ADVANCED MATERIALS
(2023)
Review
Chemistry, Physical
Sang Eon Jun, Jae Kwan Lee, Sangwoo Ryu, Ho Won Jang
Summary: Single atom catalysts (SACs) exhibit remarkable catalytic activity and excellent atomic utilization efficiency in photoelectrocatalytic water splitting. This review summarizes the representative characterization techniques and recent development in SACs for efficient photoelectrochemical water splitting.
Article
Engineering, Multidisciplinary
Yaelim Hwang, Haena Yim, Kwanyoung Oh, Jiseul Park, Sohee Kim, Ho-Won Jang, Ji-Won Choi
Summary: Silicon nitride-based electrodes (SiNx) have been proposed as candidates for high-capacity transparent anode electrodes, but their low electrical conductivity limits their application in thin film batteries. To overcome this, we introduced uniformly dispersed Ag nanoparticles in SiNx thin film to enhance electrochemical properties without affecting transmittance. The addition of Ag increased the capacity of the thin-film battery and allowed for higher C rates, while maintaining optical transmittance over 60% in the visible range.
COMPOSITES PART B-ENGINEERING
(2023)
Review
Chemistry, Inorganic & Nuclear
Jin Wook Yang, You Jin Ahn, Deok Ki Cho, Jin Young Kim, Ho Won Jang
Summary: Photovoltaic-electrochemical (PV-EC) fuel production is a promising technology that combines solar energy conversion and electrochemical catalysis. Halide perovskite solar cells with adjustable band gaps are attractive for PV-EC devices as they can boost electrochemical reactions without external power supply. This review focuses on halide perovskite PV-EC fuel generation, including device principles, band gap engineering, and material candidates for electrocatalysts. Recent advances in electrocatalysts, halide perovskite solar cells, and PV-EC devices for improving solar-to-fuel conversion efficiency are summarized.
INORGANIC CHEMISTRY FRONTIERS
(2023)
Article
Chemistry, Physical
Jun Min Suh, Young Geun Song, Jung Hwan Seo, Myoung Sub Noh, Min Gyu Kang, Woonbae Sohn, Jinho Lee, Kwangjae Lee, Donghwi Cho, Seokwoo Jeon, Chong-Yun Kang, Young-Seok Shim, Ho Won Jang
Summary: Researchers irradiate high-power lasers on existing metal-oxide nanostructures to expose the hidden inner surface, leading to enhanced surface area for chemical sensor applications and remarkable gas-sensing performance. Decorating noble metal catalysts on both inner and outer surfaces of the nanostructures results in high gas response and selectivity to volatile organic compounds. The effects of high-power laser irradiation on the morphological evolution of metal-oxide nanostructures can be numerically simulated and experimentally verified, providing a new perspective for the time-efficient development of nanostructure-based electronic devices.
Article
Chemistry, Inorganic & Nuclear
Seokjin Hong, Hyunki Kim, Ho Won Jang, Soo Young Kim, Sang Hyun Ahn
Summary: We report a simple method to fabricate cobalt iron oxyhydroxide bifunctional electrodes for an anion exchange membrane water electrolyzer. The bifunctional electrodes show high activity in overall water electrolysis and excellent stability. The resulting single cell exhibits a high current density and energy efficiency, comparable to state-of-the-art AEMWE single cells with bifunctional electrodes.
DALTON TRANSACTIONS
(2023)
Article
Nanoscience & Nanotechnology
Sol A. Lee, Jeewon Bu, Jiwoo Lee, Ho Won Jang
Summary: High-entropy alloys are near-equimolar alloys of five or more elements, which are receiving attention for their unique physical and chemical properties. In electrocatalysis, they serve as active sites in multiple elements, optimizing the adsorption/desorption property for the target reaction. High-entropy nanomaterials (HENMs) are attractive candidates as electrocatalysts due to their high surface-to-volume ratio and tailored composition. This review introduces the concept and various design strategies of high-entropy materials, discusses the recent advances of HENMs as electrocatalysts for different applications, and proposes the challenging aspects and future insight of HENMs for advanced electrocatalysis.
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)
