bluuebunny/crossref_metadata_2025 huggingface dataset:
(Invited) Device Engineering of Organic Electro-Chemical Transistors and Solar Cells
Authors: Bitton Sapir , Fadool Hela , Tessler Nir
Published: August 2024

Traditionally, new material-based technologies evolve first through chemistry and physics, with device engineering assuming a key role only towards commercialization. The device structure of an OLED pixel in any screen is a testament to the contribution of engineering to the challenge of achieving efficient and stable devices. In the talk, I will discuss two fields where this is yet to happen. The first is the organic electrochemical transistors, and the second is the solution-processed organic solar cells. Using both a detailed 2D chemical-physics semiconductor device model and a rate-equation level model, I will delve into the physics and electrochemistry of OECTs showing the role of electrode reactions and counter ions. In the context of OPVs, I will show that focusing on the performance at the maximum power point, instead of the short and open circuit, allows the design where the device contributes to charge generation and extraction.
(Invited) Transferable Organic Semiconductor Nanosheets for Van Der Waals Heterojunction Devices
Authors: Kalkan Sirri Batuhan
Published: August 2024

The combination of organic semiconductors (OSCs) and two-dimensional materials provides a new basis to harness the advantages of both material systems, for example to fabricate unipolar pentacene thin-film transistors using graphene contacts [1] and p-n junctions using pentacene and molybdenum disulfide [2]. However, the fabrication of such devices by vapor deposition of OSCs is a challenge because growth is limited by the surface-dependent diffusion of small molecules. In this talk, I will present a novel method for the preparation of transferable OSC nanosheets that overcomes this problem. Highly crystalline, wafer-scale (3") nanosheets as thin as 20 nm can be obtained by precisely delaminating the OSC layer from a water-soluble sacrificial film in an appropriate wetting geometry. These free-floating films are then deposited on arbitrary substrates while maintaining morphology and crystallinity. Consequently, we demonstrate functional OSC nanosheets on top of prefabricated electrodes and monolayer MoS2, resulting in devices such as unipolar, ambipolar, and anti-ambipolar field effect transistors [3].

References:

[1] Lee, W.H., Park, J., Sim, S.H., Lim, S., Kim, K.S., Hong, B.H. and Cho, K., 2011. Surface-directed molecular assembly of pentacene on monolayer graphene for high-performance organic transistors. Journal of the American Chemical Society, 133(12), pp.4447-4454.

[2] Jariwala, D., Howell, S.L., Chen, K.S., Kang, J., Sangwan, V.K., Filippone, S.A., Turrisi, R., Marks, T.J., Lauhon, L.J. and Hersam, M.C., 2016. Hybrid, gate-tunable, van der Waals p–n heterojunctions from pentacene and MoS2. Nano letters, 16(1), pp.497-503.

[3] Kalkan, S.B., Najafidehaghani, E., Gan, Z., Apfelbeck, F.A.C., Hübner, U., George, A., Turchanin, A. and Nickel, B., 2021. Wafer scale synthesis of organic semiconductor nanosheets for van der Waals heterojunction devices. npj 2D Materials and Applications, 5(1), p.92.
Photoluminescence and Electroluminescence Confocal Imaging of an OLED
Authors: Berry Matthew , Thomson Stuart
Published: August 2024

In recent years organic light-emitting diodes (OLEDs) have become one of the leading technologies for full-colour display panels in high-end smartphones and televisions. This rapid growth in use has occurred because OLEDs offer an all-around superior performance to liquid crystal displays (LCDs). For example, they are thinner, lighter, more flexible, less power consumptive, and brighter.

When new OLEDs are developed, the optoelectronic properties of individual components and the complete device can be characterised using photoluminescence (PL) and electroluminescence (EL) spectroscopy. In this poster presentation, we use a confocal Raman microscope to characterise and spatially resolve the optoelectronic properties of a fabricated OLED device with four imaging modalities: PL, EL, time-resolved PL (TRPL), and time-resolved EL (TREL). Using a confocal microscope to characterise an OLED's spectral and time-resolved properties provides much greater detail than bulk measurements.

Figure 1
(Invited) Breakdown Improvement of Mg-Diffused Current Blocking Layer in Ga2O3
Authors: Zeng Ke , Bian Zhengliang , Chowdhury Srabanti
Published: August 2024

The path towards an all-planar highly efficient vertical Ga2O3 transistor requires the construction of a buried gate barrier junction to circumvent the pre-mature breakdown near the gate often seen in lateral structures. An effective selective doping technique is necessary to achieve this. By taking advantage of the high diffusivity of dopants and defects in Ga2O3, we propose the use of diffusion doping as a rapid and non-invasive technique to explore the possibility of an effective current blocking layer (CBL) in vertical Ga2O3 transistors. Unlike ion implantation, diffusion doping does not require an 1100°C annealing for the repair of crystal damage. Thus, the desired Mg doping profile can be maintained by the end of device fabrication, which is the key to achieving a high blocking voltage with Mg-doped CBL. In addition, diffusion doping can easily form a much deeper dope junction and be very useful for high-voltage and super-junction devices.

Recently, we have demonstrated the first Ga2O3 vertical-diffused-barrier field-effect transistor (or VDBFET) utilizing a Mg-diffusion doped CBL with a spin-on-glass source. The transistor exhibited excellent FET behavior with decent saturation, enhancement-mode operation, and an on/off ratio of more than 109. However, the breakdown voltage is measured to be only 72V most likely due to the punch-through of the Mg-diffused CBL. This is likely caused by a lower-than-expected Mg doping rendering an inefficient electron blocking. In addition, SIMS analysis indicated the existence of Mg-H complex that deactivated the Mg. Thus, the effective Mg doping is even lower than its chemical concentration. Here we will discuss a new strategy to resolve this problem and showcase the characteristics of the improved CBL with a higher breakdown. This development paves the way for the development of high-voltage Ga2O3 VDBFETs.
Epitaxial Growth and Doping of N-Polar AlN by Plasma-Assisted Molecular Beam Epitaxy
Authors: Ahmadi Elaheh , Khan Irfan
Published: August 2024

In recent years, AlN has garnered significant attention in the research community due to its excellent electronic properties. AlN, which is an ultra-wide bandgap material with a direct band gap of 6.2 eV, has a high breakdown electric field (12 MV/cm) and high thermal conductivity. In addition, band engineering can be achieved by alloying AlN with Gallium (Ga), Indium (In), and Scandium (Sc), and two-dimensional electron gas (2DEG) is formed at the AlGaN/AlN interface due to strong piezoelectric and spontaneous polarization. Furthermore, AlN has high-temperature stability, which is suitable for application in harsh environments. Due to these unique properties, AlN has gained attention as a promising candidate for the next generation of high power electronic and optoelectronic applications.

In this talk, we present the demonstration of controllable Si doping in N-polar AlN films grown on single crystal AlN substrates by plasma assisted molecular beam epitaxy (PAMBE). Through optimization of growth conditions, we obtained high quality N-polar AlN films at high temperatures. However, our studies revealed that Si incorporation dramatically decreases at such high growth temperature. To enable higher Si incorporation, a hybrid growth scheme was developed, using a combination of low-temperature and high-temperature growth condition and by using Ga as a surfactant at low growth temperature. By lowering the growth temperature of AlN to 750°C, we were able to incorporate Si with concentrations as high as 2x1020 cm-3 and demonstrated an electron concentration as high as 1.25x1019 cm-3 at room temperature.
(Electronics and Photonics Division Poster Award Winner) A High Breakdown Voltage Silicon Carbide (SiC)/Gallium Oxide (Ga2O3) Heterojunction Diode for High Power Applications
Authors: Alshammari Nuwayyir , Maimon Ory , Li Qiliang
Published: August 2024

Wide and ultrawide bandgap semiconductors demonstrate exceptional performance due to their elevated energy bandgap. This characteristic results in breakdown electric fields surpassing those found in conventional silicon electronics by more than an order of magnitude. Furthermore, the high energy bandgap offers distinctive advantages, including enhanced efficiency, drift velocity, increased voltage blocking, and high-frequency switching, making these semiconductors crucial in pushing the boundaries of electronic technology. Gallium Oxide and Silicon Carbide, distinguished by their unique properties, contribute significantly to the advancement of power electronics. Gallium Oxide, with its wide bandgap of 4.6 – 4.9 eV and excellent thermal stability, stands out for its ability to handle high electric fields and temperatures. Silicon Carbide, on the other hand, boasts a robust combination of high thermal conductivity and a wide bandgap of 3.26 eV, making it well-suited for high-power and high-temperature applications. The combination of these two materials in a heterojunction holds promise for the development of high-performance power devices. In this study, we propose a novel high breakdown voltage Silicon Carbide (SiC)/ Gallium Oxide(Ga2O3) heterojunction diode through TCAD Sentaurus. We present a comparative study of the breakdown voltage and electric field across different heterojunction lengths and under various doping concentrations. The investigated heterojunction showcases a high breakdown voltage of 1899V, making it a promising candidate for advanced power electronics applications. Furthermore, simulation results revealed a significant increase in the breakdown voltage of the SiC/Ga2O3 heterojunction, escalating from 1899 V to 4864 V when extending the heterojunction length. Improved specific ON resistance (RON, sp) and Baliga figure-of-merit (BFOM) will also be presented.
(Invited) Functional Complex Oxides for Next-Generation Logic, Memory, Sensing, and Beyond
Authors: Martin Lane W.
Published: August 2024

Complex-oxide materials possess a range of interesting properties and phenomena that make them candidates for next-generation devices and applications. But before these materials can be integrated into state-of-the-art devices, it is important to understand how to control and engineer their response in a deterministic manner. In this talk, we will discuss some of the state-of-the-art science, engineering, and utilization of complex ferroic materials and their potential for emergent order and phenomena that can enable new device function. We will explore the role of the epitaxial thin-film growth process and the use of epitaxial constraints to engineer a range of systems with special attention to ferroelectric (i.e., materials with robust spontaneous polarization that can be switched with an electric field thereby producing a ferroelectric hysteresis loop), antiferroelectric (i.e., materials which have an antiparallel alignment of polarization (or are non-polar) in the ground state but can be switched to a polar (parallel) order by an external electric field producing a reversible antiferroelectric-to-ferroelectric phase transition and a characteristic double polarization-electric-field hysteresis loop), and relaxor (i.e., chemically complex materials that exhibit a competition between short- and long-range interactions such that it produces a complex, dynamic polarization structure and exotic properties) materials.

In recent years, the use of epitaxial constraints has enabled the production of model versions of these complicated materials and the subsequent deterministic study of an array of physical phenomena that are now being widely considered for next-generation applications. Specifically, we will investigate the potential of ferroelectric materials for non-volatile, ultra-low voltage memory and logic applications including their use in ferroelectric-field-effect transistors, the realization of multi-state/neuromorphic function, and more. In turn, we will explore how antiferroelectric and relaxor thin-film materials can open the door to a new generation of thin-film based electromechanical, sensing, high-frequency, and capacitive-energy-storage devices. Along the way we will leverage advanced thin-film growth techniques to control the materials and to solicit new insights about their function, apply state-of-the-art characterization methods, including unique in operando studies under applied stimuli, to understand how materials function, and explore how such materials can be integrated and utilized in realistic device structures. We will try to introduce the listener to these complex materials and their potential for new applications – in effect working to motivate engineers to explore these materials. The discussion will range from the development of fundamental understanding of the physics that lies at the heart of the observed effects, to an illustration of routes to manipulate and control these effects, to the demonstration of rudimentary solid-state devices based on these materials.
Investigation of Neuromorphic Behaviors in Access Regions-Integrated Van Der Waals Heterostructures
Authors: Chen Lin , Lin Shu-Ping
Published: August 2024

The emergence of neuromorphic devices has disrupted the traditional von Neumann architecture, providing a solution to the challenges of simulating neural parallel processing and power consumption in conventional computer architectures [1]. Access regions (ARs) are strategically created and positioned in proximity to source and drain electrodes, resulting in a channel that does not overlap with the floating gate (FG) [2]. In this study, we investigated ARs integrated van der Waals heterostructural field-effect transistor (AR-VH-FET) device, constructed by vertically stacking several 2D materials. Specifically, molybdenum disulfide (MoS2) served as a channel, hexagonal boron nitride (h-BN) as a tunneling layer, and graphene (Gr) as the FG. We conducted measurements on the transfer and output characteristics to characterize the electrical performance of the AR-VH-FET. Under a fixed VDS, with the application of positive and negative VBG as programming and erasing voltages respectively, we measured device retention and endurance. AR-VH-FET devices not only emulate basic neuromorphic functions but also replicate biological characteristics.

References

[1] Q. Wang, C. Zhao, Y. Sun, R. Xu, C. Li, C. Wang, W. Liu, J. Gu, Y. Shi, L. Yang, Synaptic transistor with multiple biological functions based on metal-organic frameworks combined with the LIF model of a spiking neural network to recognize temporal information, Microsystems & nanoengineering 9(1) (2023) 96.

[2] T. Sasaki, K. Ueno, T. Taniguchi, K. Watanabe, T. Nishimura, K. Nagashio, Material and device structure designs for 2D memory devices based on the floating gate voltage trajectory, ACS nano 15(4) (2021) 6658-6668.

Figure 1
Rapid Detection of Staphylococcus Epidermidis Using Electric-Double-Layer (EDL) Field-Effect Transistor (FET) Biosensors with Loop-Mediated Isothermal Amplification
Authors: Su Yi-De , Wang Yu-Lin , Chiu Chia-Lin , Thokchom Rohan , Tseng Huan-Wei , Kalaimani Vishal Mani , Lin Chia Kai
Published: August 2024

Staphylococcus epidermidis is a Gram-positive bacterium which commonly grows in human skin, nasal passages, respiratory tract, intestinal tract, air, and water. Although it is harmless to healthy individuals, immunocompromised patients are at risk of infection, which can lead to severe symptoms. With the increased reliance on antibiotics in hospitals, the antimicrobial resistance of Staphylococcus epidermidis has also risen, pointing out a challenge in clinical treatment.

Therefore, the diagnosis of this bacterium has gained significant attention. The aim of this experiment is to detect bloodstream infections (BSIs) in the shortest possible time. The study is intended to be implemented in hospitals to provide a more convenient method for medical professionals to conduct screenings. The approach involves screening for the most common disease sequence, ssDNA, followed by sequential detection of corresponding cDNA, plasmids, and bacteria. To detect bacteria with the least amount of bacteerial load, a novel isothermal amplification method called Loop-mediated isothermal amplification (LAMP) is employed to increase the concentration of DNA of BSIs bacteria before measurement. The overall time required for this process doesn’t exceed one day, significantly increasing speed for the detection of blood-borne bacteria in hospitals. The core mechanism of this platform involves the use of electric-double-layer-gated field-effect-transistors (EDL-gated FETs) to amplify the gate voltage changes generated when the ssDNA binds with complementary DNA. These voltage changes are then converted into numerical values for analysis and interpretation.

Currently, the research results show that this biomedical sensor can detect concentrations ranging from 1fM to 1pM. With the assistance of LAMP, it has successfully achieved a concentration of approximately 1yM (10-24 M) and detected with EDL-gated FETs. The experiment was also carried out step by step on simulated clinical specimens. The experiments have found successful serum nucleic acid amplification methods that provide excellent detection limits. Compared with other biomedical sensors in the past, it not only has lower detection limits but also brings features such as faster, more convenient, and more portable.

Keywords: EDL, FET, Staphylococcus epidermidis, Biosensor, LAMP

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Development of Thermoelectric Nanomaterials with Photothermal Effect to Enhance Thermalcatalysts Sterilization Applications
Authors: Wang Ching-Wen , Lin Zong-Hong
Published: August 2024

Reactive oxygen species (ROS) are widely used in environmental and health-related fields due to their high reactivity. Among them, hydrogen peroxide (H2O2) is the most mild, stable, and environmentally friendly oxidant with only H2O and O2 as the decomposition products. Therefore, it is widely used in bleaching, wastewater treatment, fuel cells, and medical which can using on sterilization or infective wound healing and so on. However, the traditional anthraquinone method for producing H2O2 requires precious metal catalysts、high energy consumption and produces a large amount of wastewater. In addition, the catalytic production of H2O2 is mainly achieved by photocatalysis, piezocatalysis, or electrocatalysis procresses, which limits the application environment. To solve this problem, thermocatalysis based on temperature difference by using thermoelectric materials is a promising solution. However, the current H2O2 production efficiency is still low, which limits the application scenarios. Therefore, we propose to use Au nanoparticles and MoS2 nanosheets with Bi2Te3 nanoplates as the thermocatalytic material. Bi2Te3 nanoplates have high Seebeck coefficient at room temperaturea and high specific surface area. Moreover, Au nanoparticles and MoS2 nanosheets are known as great photothermal property materials which can be used to increase the temperature difference of the material to improve the H2O2 production efficiency. The temperature difference is the most common environmental factor in daily life, which makes thermoelectric nanomaterials have great potential for practical applications in the field of thermalcatalysts.
(Invited) the Development of Multifunctional Nanopipette Based Biosensors
Authors: He Jin
Published: August 2024

In recent decades, the field of nanoscale electrochemistry has advanced rapidly in ultrasensitive electroanalysis at the single-particle level. The glass/quartz nanopipette has emerged as an economical, readily accessible, versatile, and powerful tool for single-entity electrochemistry. We have integrated nanoelectrode and nanopore based techniques using the so-called multifunctional nanopipette, which includes both nanopore and nanoelectrode at the orifice of the nanopipette tip. The multifunctional nanopipette has been successfully used with both amperometric and potentiometric methods for protein and small biomolecule analysis and detection at the single-molecule level. The nanopipette has also been used for intracellular delivery and counting, as well as nanoelectrophyiology of excitable cells.
(Invited) Designing Materials for Organic Electrochemical Transistors
Authors: Kayser Laure
Published: August 2024

Organic electrochemical transistors (OECTs) have gained a renewed interest in the field or bioelectronics and biosensors. OECTs act as amplifiers and therefore provide high signal/noise ratio for detecting a wide range of biomolecules or physiological signals. A critical component of the OECTs is the channel material, which is an organic mixed ionic-electronic conductor (OMIEC). In simpler terms, OMIECs are (semi)conducting polymers that can transport electronic charges (electrons or holes), transport ionic charges, and display a capacitive behavior (reversible doping/dedoping process). Amongst OMIECs, the polyelectrolyte complex PEDOT:PSS has been the most widely used, likely due to its commercial availability and ease of use as a water dispersion. PEDOT:PSS, however, is a black box with a proprietary composition and does not have particularly reactive handles for functionalization. As such, it is difficult to modify its properties for specific applications in biosensing. In this talk, I will describe my team’s work in understanding PEDOT:PSS and methods for modifying it using covalent organic chemistry. Our principal approach is to control the synthesis of the PSS polymer and/or modify it with functional units by using random or block copolymerization. This approach was successfully used to achieve high performance OECT devices and new conductive materials with temperature or light-response.
(Invited) Battery-Free Wearable and Implantable Electronics for Chronic Disease Management
Authors: Niu Simiao
Published: August 2024

60% of Americans live with at least one chronic disease. These diseases and their associated comorbidities are now the leading causes of death in the United States. The effective management of complex chronic diseases requires body-wide, long-term, accurate, and continuous monitoring of multiple physiological signals from wearable and implantable devices to precisely determine the pathological state. Wearable physiological signal monitoring can dramatically reduce the demand for physician visits and increase patients' engagement and treatment adherence rates. Specifically, battery-free wearables and implantable electronics reduce device volume and mechanical stiffness, significantly improving wear comfort, which is highly desirable for next-generation wearable and implantable electronics. However, battery-free wearables and implantable electronics still face many challenges, mainly wireless energy and data transfer. To address these challenges, my research has been involved in the exploration of rational system design concepts, material and device fabrication innovation, and tailored algorithms to enable smart battery-free wearables and implantable electronics targeting next-generation chronic disease management.

Here, I would like to discuss two of my developed technology platforms to elaborate on the concept of battery-free wearable and implantable systems. First, I will describe an RFID-based body area sensor network technology platform. This technology uses electromagnetic waves and RF antennas as energy and data transmission media and has broad applications in sleep tracking, workout monitoring, chronic wound healing, and inflammation management. Second, I will describe a triboelectric transducer-based implantable battery-free device. This technology platform uses ultrasound waves and triboelectric transducers as energy and data transmission media and has broad applications in implantable sensing. Overall, the developed technology platforms can assess multiple health outcomes and treatment responses to various chronic diseases. Ultimately, this technology will help reduce the burden of chronic diseases, lower medical costs, and provide a better quality of life for patients. (1,2,3,4)

References:

1. "A Wireless Body Area Sensor Network System Based on Stretchable Passive Tags". Nature Electronics 2019, 2, 361.

2. "High-Frequency and Intrinsically Stretchable Polymer Diodes". Nature 2021, 600, 246-252.

3. "Wireless, closed-loop, smart bandage with integrated sensors and stimulators for advanced wound care and accelerated healing". Nature Biotechnology 2023, 41, 652-662.

4. “An Ultrasound-Driven Implantable Wireless Energy Harvesting System Using Triboelectric Transducer”. Matter 2022, 5, 4315-4331.
(Invited) Triboelectric Nanogenerators for Self-Powered Sensing and Human-Machine-Interfaces
Authors: Cao Changyong Chase
Published: August 2024

Wearable and portable electronics are garnering substantial interest for applications ranging from personalized healthcare monitoring to implantable devices and prosthetics. The demand for long-term operation poses significant challenges to their power supply. To address this, the development of novel self-powered systems holds considerable promise. In this talk, I will discuss our recent advancements in crafting triboelectric nanogenerators (TENGs) for self-powered sensing and human-machine interfaces (HMIs). I will first introduce our multifunctional tactile sensors inspired by human skin. These sensors combine a triboelectric nanogenerator layer with a piezoresistive sensing layer, emulating the ability of human skin to detect a variety of static and dynamic stimuli. This sensor can successfully recognize voice patterns, monitor physiological signals, and track human motion in real-time. Then, I will unveil our self-powered smart packaging system, which is driven by a novel desiccant-based triboelectric nanogenerator (D-TENG). This system offers a viable method for continuous monitoring of product conditions and quality control throughout the supply chain, thus minimizing food waste and maintaining a comprehensive log of logistics, especially critical in vaccine transport. Lastly, I will present our novel breath-driven triboelectric sensor in respiratory monitoring. This sensor can precisely detect breath variations and convert different breathing patterns into electrical signals, all without impeding normal breathing. It enables severely disabled individuals to control household appliances through a breath-driven HMI and provides an intelligent monitoring system for emergency situations. This innovative work paves the way for future development in self-powered sensors and advanced HMIs, enhancing assistive technology for individuals with disabilities.
(Invited) Triboelectric Identification of Amino Acids
Authors: Lin Zong-Hong
Published: August 2024

Triboelectrification necessitates a frictional interaction between two dissimilar materials, and their contact electrification is characteristically based on the polarity variance in the triboelectric series. Utilizing this fundamental advantage of the triboelectric phenomenon, different materials can be identified according to their contact electrification capability. Herein, we perform an in-depth analysis of the amino acids present in the stratum corneum of human skin, and we quantify them regarding triboelectric polarization. The principal focus of this study lies in analyzing and identifying the amino acids present in copious amounts in the stratum corneum to explain their positive behavior during the contact electrification process. Thus, we present an augmented triboelectric series of amino acids with quantified triboelectric charging polarity by scrutinizing the transfer charge, work function, and atomic percentage. Furthermore, we detect the chirality of aspartic acid as it is most susceptible to racemization with clear consequences on the human skin. We expect this study to accelerate research exploiting triboelectrification and provide valuable information on the surface properties and biological activities of these important biomolecules.
Rapid Detection of Methicillin Resistant Staphylococcus Aureus (MRSA) Using Electric-Double-Layer (EDL) Field-Effect Transistor (FET) Biosensors
Authors: Tseng Huan-Wei , Lin Chia Kai , Kalaimani Vishal Mani , Thokchom Rohan , Su Yi-De , Wang Yu-Lin
Published: August 2024

According to the latest statistics and analysis by American researchers based on the data from 195 countries worldwide, it has been found that one person in every five people died due to sepsis. The annual death caused by sepsis reaches up to eleven million people, and the number of deaths from sepsis is even higher than those from cancer. We believe that the detection of MRSA is necessary.

Staphylococcus aureus is the most common pathogen of sepsis. Methicillin-resistant Staphylococcus aureus (MRSA) or Multiple-resistant Staphylococcus aureus is a distinct strain of Staphylococcus aureus. It has mecA gene which codes for penicillin binding protein 2a (PBP 2A) that will remain active under beta lactams antibiotics. This gives bacterial the ability to grow under concentrations of beta-lactam antibiotics which leads to MRSA's resistance to almost all the different penicillin-type antibiotics including methicillin and other beta-lactamase-resistant penicillins.

To detect MRSA in the shortest possible time, we adopt field-effect transistor (FET) biosensor for the real-time detection of binding reactions between DNA probe and cDNA. We select DNA probe sequence of mecA to be the aptamer and immobilize probe DNA which are complementary to the target cDNA on the sensor. This process allows DNA strands to attach to the gold surface. After that, we detect the binding reaction of DNA probe and cDNA by analyzing electrical response of field-effect transistor (FET). We can observe that the Id current changes after cDNA hybridizes with DNA probe.

In conclusion, in our research results, Field-effect transistor (FET) biosensor can detect concentration ranging from 1fM to 1pM. In addition, we can achieve other advantages such as more portable, higher sensitivity, real-time monitoring capability, and lower detection limits. With this rapid detection procedure, we can do early diagnosis and treatment, thus improving the quality of human life.

Keywords: FET, EDL, Aptamer, DNA, MRSA

Figure 1
Wearable Pressure Sensing System Appliedin Sports Assistive Monitoring and Technological Rehabilitation
Authors: Hsu Wei-Zan , Lin Zong-Hong
Published: August 2024

In the aging society, chronic diseases have become a very common problem. Many elderly people have at least one chronic disease. Most chronic diseases are caused by poor diet and lack of physical activity. As the body ages, chronic diseases will develop. Therefore, it is important to establish a healthy lifestyle. The best way to prevent chronic diseases is to diagnose them early and self-check your health. In terms of self-check, most hospitals provide good testing equipment for the public to use. However, in Taiwan, most elderly people with chronic diseases are not aware of any abnormalities in their bodies. They often go to the hospital for a doctor's check only after experiencing a serious injury. For example, diabetic patients are tend to foot pressure distribution imbalance and foot deformation due to peripheral nerve damage caused by diabetes. In severe cases, long-term friction can cause wound infection and lead to amputation. Parkinson's disease, which commonly occurs in the elderly, is the main cause of falls in the elderly. Therefore, early self-check is very important.We used TENG technology to develop high-performance pressure sensors. The sensors are made of biocompatible silicone and conductive silicone, which are soft, flexible, and durable. We installed the sensors in insoles. We hope that by allowing patients to wear corrective insoles to detect the current foot pressure in real time, we can first collect data on the pressure distribution and walking frequency of healthy people. Then, we can compare the data to abnormal walking patterns. Finally, we can use machine learning to analyze and classify the data to predict the risk of patients developing complications of chronic diseases. This allows patients to do a simple self-check at home without having to go to a large hospital for a complex examination, which also avoids wasting unnecessary medical resources.
New Charged Interfaces for Energy Conversion and Catalysis
Authors: Fan Feng Ru
Published: August 2024

Charged interfaces are key areas for charge transfer and chemical reactions. Studying these interfaces at the microscopic level, especially in constructing and characterizing specific structures, understanding charge transfer, and managing chemical reactions, is crucial but challenging. Our work focuses on three innovative interface structures: solid/solid triboelectric, liquid/gas electrified, and solid/ultrathin heterojunction interfaces. We have achieved significant insights into the charge transfer mechanisms within these electrified systems and effectively controlled catalytic reactions at these interfaces.

Key findings include:

Development of new concepts for contact electrification and electrostatic-induced coupling at solid/solid interfaces, leading to novel applications in energy conversion and catalysis. We introduced the concept of mechanical-electric-catalytic reactions based on triboelectric interfaces and achieved direct synthesis of hydrogen peroxide through friction-catalysis under normal conditions.

Effective control of reaction kinetics and selectivity in charged microdroplet liquid/gas electrified interfaces by adjusting parameters like droplet evaporation rates and electric field characteristics. This approach led to efficient production of hydrogen peroxide and selective conversion of carbon dioxide.

Precise atomic-level construction and sub-nanometer characterization of solid/ultrathin heterojunction interfaces, exemplified by gold/graphene interfaces. This included the development of a gold/ultrathin palladium/single-layer ruthenium structure, enabling in-depth study of hydroxylation reactions and the influence of palladium interlayers on ruthenium's catalytic efficiency.
(Invited) Application of Nanostructure for Improving the Interfacial Interactions between Sensing Surface and Targeted Particles
Authors: Lin Shu-Ping
Published: August 2024

Various interfacial interactions, encompassing screened Coulomb (electrostatic double layer) forces, Lifshitz-van der Waals forces, hydrophobic/hydrophilic interactions, as well as steric, chemical, morphological, and roughness effects, have been confirmed to play a crucial role in governing the interaction between target particles and the sensing surface. Small protrusions on the sensing surface can induce substantial variations in the surface’s interaction with the target analytes based on the extended Derjauin-Landau-Verwey-Overbeek (DLVO) theory. 1 Here, indium tin oxide coated vertical nanowires served as nanostructure to investigate interfacial interactions between the sensing surface and targeted analytes. Analyzing the ratio of particle size to asperity size on the sensing surface within the extended DLVO theory revealed that surface roughness can provide sufficient interfacial interactions with target analytes, thereby enhancing the electrical sensing performance. Upon immersing the nanostructural sensing surface in an analyte solution, electrical signals undergo a significant shift owing to alterations in the surface potential at the interface between the functionalized sensing surface (such as antibodies or chemical functional groups) and the analyte solution. 2, 3 These observations highlight the critical role of nanostructure on the sensing surface, particularly with adequate surface roughness, in significantly improving sensing performance by facilitating effective interaction of the surface with the target analyte based on the extended DLVO theory.

References:

Huang, X.; Bhattacharjee, S.; Hoek, E. M. V., Is Surface Roughness a “Scapegoat” or a Primary Factor When Defining Particle−Substrate Interactions? Langmuir
2010,
26 (4), 2528-2537.

Lin, S.-P.; Lee, W.-J.; Sun, M.-C.; Yang, Y.-H.; Vinzons, L. U.; Lin, Y.-M.; Wei, Y.-T., Nano-Brush Structure for Rapid Label-Free Differentiation of Alzheimer’s Disease Stages and Direct Capture of Neuron-Derived Exosomes from Human Blood Plasma. ACS Applied Materials & Interfaces
2023,
15 (48), 56478-56489.

Yang, Y.-P.; Lu, Y.-L.; Kumar Gupta, A.; Lin, S.-P., Real-Time Impedimetric Detection of Cardiac Troponin I Using ITO-Coated Vertically Aligned Silicon Nanowires. Mater. Lett.
2022,
311, 131575.

Figure 1
(Invited) Nanoarray Configured Monoliths for Self-Monitored Multi-Phase Reactive Processes
Authors: Gao Pu-Xian
Published: August 2024

The incorporation of multiple functions synergistically into one device or platform can enable additions of application merits such as light weight, ease for system integration, reduced system complexity, cost-effectiveness, and programmability. This is especially true for usually complex energy, environmental, and biological systems with the integration need of many active or passive devices and components of various functionalities. In this work, we demonstrated a compact nanoarray configured monolith design with the ability to function as both a catalyst and a sensor to enable the self-monitoring of the complex multi-phase catalytic reaction processes during operation. A bimodular approach has been realized using both electrical and electrochemical interrogation modes for reactive gas and solid phase monitoring directly using the built-in catalysts. This new type of compact and built-in monolithic sensor configuration can lower the catalytic energetics and detect gas/solid composition semi-quantitatively at room temperature up to elevated temperature. Robust calibration curves of built-in sensor responses can be achieved with facile data processing and analyzing. The built-in monolith sensor shows good sensitivity and good selectivity sufficient for the self-monitoring of the reaction process. Besides, the nanoarray based monolith device has shown good environmental tolerance toward practical applications. Such compact monolithic device can serve as a self-monitored reactor, filter, and other function component that can potentially allow in-situ and real time monitoring and functional process control in complex and reactive physical and chemical environments. With further refining of the design and functional integration, this new type of smart monolithic device can provide necessary data and knowledge for future computation-driven situational awareness prediction and intelligent control of various complex dynamic processes and systems.
(Invited) Tellurene Wearable Sensors
Authors: Wu Wenzhuo
Published: August 2024

The development of wearable sensors for continually monitoring biomarkers is a promising alternative to the costly tools currently utilized in healthcare. Two-dimensional (2D) materials exhibit high sensitivity to physiology-relevant signals. However, few studies report 2D materials-based wearable sensors, primarily due to the intrinsic limitations of related materials that render them poor performance for sensing. Ongoing efforts in 2D materials also face difficulty scaling up due to restrictions on the synthesis conditions and stability. I will discuss our recent progress in developing tellurene-based wearable sensors with multiple modalities for continuously monitoring vital signs. We show that wearable sensors based on tellurene, an emerging 2D semiconductor with intriguing properties, hold substantial promise for addressing the challenges of implementing 2D materials wearable sensors with high sensitivity and specificity. We aim to leverage our platform to fill the gaps in developing clinically applicable 2D materials-based wearable sensors.
(Invited) Electric-Driven Preconcentrating Microfluidic Device for Enhancing Biomolecular Sensing
Authors: Fan Yu-Jui
Published: August 2024

Preconcentration of biomolecules for detection on microfluidic platforms based on electrical kinetic trapping (EKT) through ion concentration polarization (ICP) has been well developed in the past decade. Biomolecules can be entrapped due to the equilibrium of forces between electro-osmosis and ICP when applying a voltage to the system. In tis study, I will introduce different type of ICPs including theory, mechanism and their limitation. I will also clarify the experimental ICP results based on different microfluidic channel design. A triboelectric nanogenerator (TENG)-driven nanofluidic preconcentrating device that is able to trigger ICP and subsequently cause the EKT of the biomolecules without using a conventional electrical power source was also introduced. The EKT and electrical characteristics of the TENG-based nanofluidic preconcentrator were studied. The preconcentration factors of the device can be found to be ~1000 folds. Several examples of preconcentration device integrating to biosensing techniques are presented in this talk. Some biomarkers are also demonstrated. Further, I will also demonstrate that these biosensors, combining with preconcentrators, can be integrated to a smartphone reader.
Detection of Thiocholine for Pesticide Qualification Using Indium-Tin-Oxide-Coated Vertically Aligned Silicon Nanowires Extended Gate Field-Effect Transistor
Authors: Wei Yu-Ting , Chao Yu-Chan , Lin Shu-Ping
Published: August 2024

Thiocholine is the hydrolysis of acetylthiocholine (ATCh) by acetylcholinesterase (AChE). The detection of thiocholine can be utilized to assess the activity and inhibitors of AChE, making it a valuable recognition element for constructing biosensors used in pesticide detection[1, 2]. The enzymatic hydrolysis of ATCh is catalyzed by AChE. First, high-aspect-ratio vertically aligned silicon nanowires (VASiNWs) were successfully fabricated through metal-assisted chemical etching (MACE). To investigate the impact of nanostructures on enhancing the sensitivity of the extended gate of the field-effect transistor (EGFET), the gate terminal was connected to 3-mercaptopropyl trimethoxysilane (MPTMS) modified indium-tin-oxide (ITO)-coated VASiNWs for the electrical detection of ATCh-catalyzed thiocholine, as illustrated in Figure 1. Various solutions of ATCh-catalyzed thiocholine were collected by applying different concentrations of ATCh (ranging from 2 mM to 10 mM) to the AChE-coated wells independently for 10 minutes. Subsequently, these solutions were introduced to the MPTMS modified ITO-coated VASiNWs EGFET, and the change in drain current was measured using a semiconductor parameter analyzer (HP 4145B). The thiocholine current demonstrated a sensitivity of 29.39 uA/concentration and a linearity of 0.88. Exploring the potential of pesticides to inhibit AChE hydrolysis represents a significant breakthrough, paving the way for the advancement of biosensors in pesticide detection.

References

Liu, G., et al., Sensitive electrochemical detection of enzymatically generated thiocholine at carbon nanotube modified glassy carbon electrode. Electrochemistry Communications, 2005. 7(11): p. 1163-1169.

Pandey, P.C., et al., Acetylthiocholine/acetylcholine and thiocholine/choline electrochemical biosensors/sensors based on an organically modified sol–gel glass enzyme reactor and graphite paste electrode. Sensors and Actuators B: Chemical, 2000. 62(2): p. 109-116.

Figure 1
(Keynote) Soft Microfluidic Analysis Systems for the Skin
Authors: Rogers John
Published: August 2024

Recent advances in materials science, chemical engineering and mechanics design establish the foundations for high performance classes of microfluidic lab-on-a-chip technologies that have physical properties matched those of the human skin. The resulting devices can integrate with the surface of the skin in a water-tight yet physically imperceptible fashion, to provide real-time measurements of sweat rate and total sweat loss, along with continuous, clinical-quality biochemical information on physiological status using a combination of colorimetric and electrochemical techniques. This talk summarizes the key ideas and presents application examples in sports performance, worker safety, medical diagnostics and nutritional monitoring.
(Invited) Wearable Electrochemical Devices for Sensing and Treatment of Chronic Wounds
Authors: Bandodkar Amay J
Published: August 2024

Chronic wounds are characterized by impaired healing and affect millions globally. These wounds result from a variety of factors, including pressure ulcers, venous and arterial insufficiencies, peripheral neuropathy, diabetes mellitus, and surgical complications. Present wound assessment and treatment strategies are expensive and ineffective. For example, widely used visual wound assessment methods lack diagnostic rigor. Wound biopsies address this issue but are expensive, time consuming, and invasive. Similarly, on the treatment side, current FDA-approved products are expensive, have short shelf-life, and achieve complete healing in ~50% cases at best. In this talk I will discuss my group’s approaches to addressing these key issues in wound care using innovative electrochemical devices. Specifically, I will provide details of how we are using new self-powered electrochemical sensors and water-powered biocompatible batteries for wound care applications.
Triboelectric Nanosensor Fabricated on Robotic Platform for Self-Powered Detection of Heavy Metal Ions in Aquatic Environments
Authors: Khan Arshad , Ganguly Anindita , Huang Yan-Tsz , Lin Zong-Hong
Published: August 2024

The escalation of heavy metal ions pollution, caused by the natural processes as well as human activities has emerged as a significant global challenge. The accumulation of heavy metal ions in the human body primarily occurs through water and food consumption which poses a severe threat leading to irreversible health damage. To address this issue, the World Health Organization (WHO) has established permissible limits for various heavy metal ions in drinking water, ranging from 0.003 to 3 ppm. When these limits are exceeded, water is deemed contaminated which necessitates effective monitoring and detection strategies. Robotic chemical sensing platforms have become indispensable for tackling chemical threats by detecting harmful pollutants in toxic environments. However, chemical sensors integrated with robotic platforms encounter drawback such as reliance on external power sources. In response to this challenge, our approach integrates a highly sensitive, self-powered triboelectric nanosensor (TENS) into a robotic platform charged by a thermoelectric generator (TEG) and equipped with wireless transmission capabilities. This integration enables the rapid on-site detection of heavy metal ions. The system employs copper electrodes modified with ion-selective membranes (ISM) as sensing probes and solid triboelectric contact materials. Through periodic contact-separation cycles with ionic solutions, the system generates electrical output, facilitating the detection of various concentrations of Pb2+, As3+, and Cr6+ ions. The ionophores in the respective ISMs contribute to the selective binding capacity of the sensing probe to the particular ion. This self-powered robotic platform provides an innovative and cost-effective solution for automated chemical sensing in water environments. Its advantages include the avoidance of external power sources, low-cost operation, and the elimination of the need for frequent battery replacements. With its capability for remote monitoring and detection, this system emerges as an ideal tool for preventing and controlling heavy metal ions pollution, ultimately contributing to the intelligent monitoring of heavy metal ions in aquatic environments.

Keywords: Heavy metal ions, Solid-liquid triboelectric nanosensor, Robotic platform, Self-powered detection, Copper electrodes.