Advanced Devices Research Articles

Impact of passivation on GaS nanoflakes: A study on stability, electronic, spectroscopy, and photocatalytic properties

This study uses first-principle calculations to investigate the properties of pristine and passivated gallium sulfide nanoflakes. Passivation significantly enhances stability, with fluorinated nanoflakes being the most stable and pristine nanoflakes the least stable, having formation energies of −0.058 eV/atom and −0.009 eV/atom, respectively. The pristine and passivated nanoflakes show semiconducting band gap, which lies in a visible region. Hydrogenated nanoflakes exhibit the largest band gap of 3.62 eV, making them highly suitable for photocatalysis, while fluorine and chlorine passivation result in band gaps of 3.16 eV and 3.01 eV. Scanning tunneling microscopy reveals distinct topographical features for each passivated nanoflake, affecting their electronic properties, including negative differential conductance, making it suitable for advanced switching devices and sensors. The quantum capacitance value of 815 µF/cm2 for chlorinated nanoflakes suggests that passivated nanoflakes could be beneficial for supercapacitor applications. Spectroscopic studies show that passivation changes the infrared spectrum and moves absorption spectra from the ultraviolet to the visible range. The hydrogenated nanoflakes are found ideal for water splitting, and adjusting the pH can further optimize its photocatalytic performance. These findings highlight the potential of passivated nanoflakes in photovoltaics, biomedical imaging, photocatalysis, and advanced technological devices.

Polysomnographic phenotypes: predictors of treatment response in Obstructive Sleep Apnea with Mandibular Advancement devices

Polysomnographic phenotypes: predictors of treatment response in Obstructive Sleep Apnea with Mandibular Advancement devices

Development Trends and Prospects of Technology-Based Solutions for Health Challenges in Aging Over the Past 25 Years: Bibliometric Analysis.

As the global population ages, we witness a broad scientific and technological revolution tailored to meet the health challenges of older adults. Over the past 25 years, technological innovations, ranging from advanced medical devices to user-friendly mobile apps, are transforming the way we address these challenges, offering new avenues to enhance the quality of life and well-being of the aging demographic. This study aimed to systematically review the development trends in technology for managing and caring for the health of older adults over the past 25 years and to project future development prospects. We conducted a comprehensive bibliometric analysis of literatures related to technology-based solutions for health challenges in aging, published up to March 18, 2024. The search was performed using the Web of Science Core Collection, covering a span from 1999 to 2024. Our search strategy was designed to capture a broad spectrum of terms associated with aging, health challenges specific to older adults, and technological interventions. A total of 1133 publications were found in the Web of Science Core Collection. The publication trend over these 25 years showed a gradual but fluctuating increase. The United States was the most productive country and participated in international collaboration most frequently. The predominant keywords identified through this analysis included "dementia," "telemedicine," "older-adults," "telehealth," and "care." The keywords with citation bursts included "telemedicine" and "digital health." The scientific and technological revolution has significantly improved older adult health management, particularly in chronic disease monitoring, mobility, and social connectivity. The momentum for innovation continues to build, with future research likely to focus on predictive analytics and personalized health care solutions, further enhancing older adults' independence and quality of life.

Tailoring magnetism in chromium-doped zinc cobalt ferrite nanostructure for advanced spintronic memory devices

Soft magnetic ferrites serve as a crucial component in a wide array of sensing and actuating applications across various industries, including consumer electronics, automotive systems, spintronics, and more. These materials also find utility in spintronics, particularly for next-generation magnetic random-access memory (MRAM) due to their excellent inductive properties, which enhance the performance and scalability of spintronic memory devices. This study focuses on fine-tuning soft magnetic ferrites for inductive applications by doping them with Cr ions. By utilizing advanced experimental techniques such as the vibrating sample magnetometer (VSM) for bulk magnetometry and X-ray magnetic circular dichroism (XMCD) alongside X-ray absorption spectroscopy for atomic studies, the research aims to investigate the structural, electronic, and magnetic properties of the nanoferrites. Addition of doping in the soft ferrites observes reduction in the general magnetic parameters, with the only exception being coercivity, which decreases from 381 Oe to 275 Oe as the doping concentration increases from x = 0 to x = 0.02, and then increases to 350 Oe at x = 0.03. Through such precise tuning of the nanoparticles, this study aims to investigate the controllable soft magnetic properties of the nanoferrites, thereby paving the way for fast access times, non-volatility, and low energy consumption, presenting a compelling alternative to conventional memory technologies.

Features and Limitations of Robotically Assisted Percutaneous Coronary Intervention (R-PCI): A Systematic Review of R-PCI.

Background: Ischaemic heart disease is one of the major drivers of cardiovascular death in Europe. Since the first percutaneous coronary intervention (PCI) in 1977, developments and innovations in cardiology have made PCI the treatment of choice for stenotic coronary artery disease. To address the occupational hazards related to chronic exposure to radiation and wear and tear from heavy lead-based radioprotective aprons, the concept of robotically assisted PCI (R-PCI) was introduced in 2005. Aim: To explore the features and limitations of R-PCI, we first discuss the concept and evolution of R-PCI platforms and then systematically review the available clinical data. Methods: A systematic review has been performed across the Pubmed, Embase and Cochrane databases in order to assess the efficacy and safety of R-PCI. Secondary endpoints, such as operator and patient exposure to radiation, contrast volume used and procedural time, were assessed when available. Results: In selected patients, R-PCI provides high technical and clinical success rates, ranging from 81 to 98.8% and from 93.3 to 100%, respectively. In-hospital and 1-year MACE rates ranged from 0 to 10.4% and 4.8 to 10.5%, respectively. R-PCI is able to significantly reduce the operator's exposure to radiation. Further research analysing the patient's and cath lab staff's exposure to radiation is needed. Therapy escalation with R-PCI seems to be limited to complex lesions. R-PCI procedures add approximately 10 min to the procedural time. Conclusions: The efficacy and safety of R-PCI have been proven, and R-PCI is able to significantly reduce occupational hazards for the first operator. The lack of adoption in the community of interventional cardiologists may be explained by the fact that current generations of R-PCI platforms are limited by their incompatibility with advanced interventional devices and techniques needed for escalation in complex interventions.

High Performance MXene/MnCo2O4 Supercapacitor Device for Powering Small Robotics.

The development of advanced energy storage devices is critical for various applications including robotics and portable electronics. The energy storage field faces significant challenges in designing devices that can operate effectively for extended periods while maintaining exceptional electrochemical performance. Supercapacitors, which bridge the gap between batteries and conventional capacitors, offer a promising solution due to their high power density and rapid charge-discharge capabilities. This study focuses on the fabrication and evaluation of a MXene/MnCo2O4 nanocomposite supercapacitor electrode using a simple and cost-effective electrodeposition method on a copper substrate. The MXene/MnCo2O4 nanocomposite exhibits superior electrochemical properties, including a specific capacitance of 668 F g-1, high energy density (35 Wh kg-1), and excellent cycling stability (94.6% retention over 5000 cycles). The combination of MXene and MnCo2O4 enhances the redox activity, electronic conductivity, and structural integrity of the electrode. An asymmetric supercapacitor device, incorporating MXene/MnCo2O4 as the positive electrode and Bi2O3 as the negative electrode, demonstrates remarkable performance in powering small robotics and small electronics. This work underscores the potential of MXene-based nanocomposites for high-performance supercapacitor applications, paving the way for future advancements in energy storage technologies.

Unveiling the Twisted Aromatic Donor Effect on the Nonlinear Response of D-π-A Type Malononitrile-Derived Chromophores.

This study presents the design, synthesis, and comprehensive characterization of a novel series of D-π-A type malononitrile-derived chromophores, BTC-1-BTC-4. Combining various spectroscopic techniques, nonlinear Z-scan measurements, and quantum chemical calculations, we revealed the intricate relationship between nonlinear optical properties and the interplay of molecular structure, intramolecular charge transfer (ICT), and dipole moments (μ). Our experimental and computational findings corroborate that the polarization degree in the ground state, the charge separation in the excited state and twisted intramolecular charge transfer (TICT) collectively dictate the nonlinear optical properties of the compounds. Notably, BTC-1 exhibits an exceptional nonlinear absorption coefficient β value (2×10-8 m W-1), attributed to its optimized charge transfer efficiency and pronounced degree of charge separation. Our findings provide actionable insights for the rational design of high-performance organic Nonlinear optics (NLO) materials with potential applications in advanced photonic devices.

Microfluidics and Nanofluidics in Strong Light-Matter Coupling Systems.

The combination of micro- or nanofluidics and strong light-matter coupling has gained much interest in the past decade, which has led to the development of advanced systems and devices with numerous potential applications in different fields, such as chemistry, biosensing, and material science. Strong light-matter coupling is achieved by placing a dipole (e.g., an atom or a molecule) into a confined electromagnetic field, with molecular transitions being in resonance with the field and the coupling strength exceeding the average dissipation rate. Despite intense research and encouraging results in this field, some challenges still need to be overcome, related to the fabrication of nano- and microscale optical cavities, stability, scaling up and production, sensitivity, signal-to-noise ratio, and real-time control and monitoring. The goal of this paper is to summarize recent developments in micro- and nanofluidic systems employing strong light-matter coupling. An overview of various methods and techniques used to achieve strong light-matter coupling in micro- or nanofluidic systems is presented, preceded by a brief outline of the fundamentals of strong light-matter coupling and optofluidics operating in the strong coupling regime. The potential applications of these integrated systems in sensing, optofluidics, and quantum technologies are explored. The challenges and prospects in this rapidly developing field are discussed.

Comprehensive analysis of Nd0.5Ba0.5CoO3 cobaltite: Unveiling electrical, optical and magnetic characteristics for optoelectronic applications

In this study, we successfully synthesized the perovskite cobaltite Nd0.5Ba0.5CoO3 (NBCO) using the sol-gel method and thoroughly characterized its optical and magnetic properties. Optical measurements, using UV absorption, the Tauc model, and diffuse reflectance spectroscopy (DRS), revealed multiple direct bandgap energies, with the most significant values being 5.23 eV (Tauc method), 5.1 eV (DRS), and 4.9 eV (reflectance). The high bandgap energies highlight NBCO's suitability for UV and optoelectronic applications. The refractive index varied between 2.48 and 3.55, while the Urbach energy was measured at 2.32 eV, indicating a moderate level of localized disorder. Magnetic characterization demonstrated a ferromagnetic-to-paramagnetic transition at 125 K, with strong molecular field effects influencing the exchange interactions. The dielectric analysis revealed an exceptionally low loss factor (tan δ ≈ 0.0012), underscoring NBCO's potential for efficient energy storage and electronic applications. These results show that NBCO offers a unique combination of high optical bandgaps, strong magnetic properties, and low dielectric loss, making it a promising candidate for advanced optoelectronic and magnetic devices.

Conductivity optimisation of graphene oxide-M13 bacteriophage nanocomposites: towards graphene-based gas micronano-sensors

Graphene oxide (GO) and M13 bacteriophage can self-assemble to form ultra-low density porous structures, known as GraPhage13 aerogels (GPA). Due to the insulating nature of GPA and the challenges in producing highly conductive aerogels, it is paramount to explore ways to enhance the conductivity of GPA. Herein, we have developed a method to enhance the conductivity of GPA, via the integration and optimisation of 5 nm and 20 nm diameter gold nanoparticles (AuNPs) into the aerogel structure and systematically analysed the morphology, composition and spectroscopic properties of the resulting GPA-Au nanocomposite. The fabricated GPA-Au nanocomposites exhibited remarkable increases in conductivity, with the integration of 5 nm AuNPs leading to a 53-fold increase compared to GPA, achieving a performance of up to 360 nS/cm, which is within the range suitable for miniaturised semiconductor devices. The mechanism behind the conductivity enhancement was further investigated and attributed to GO-AuNP interactions increasing the carrier density by introducing new energy levels in the GO band gap or shifting its Fermi level towards the conduction band. These findings demonstrate the potential of functionalised AuNPs to significantly improve the electrical properties of GPA, paving the way for their application in gas sensors for biological and chemical detection and a new range of advanced semiconductor devices.

Flexible multimaterial fibers in modern biomedical applications.

Biomedical devices are indispensable in modern healthcare, significantly enhancing patients' quality of life. Recently, there has been a drastic increase in innovations for the fabrication of biomedical devices. Amongst these fabrication methods, the thermal drawing process has emerged as a versatile and scalable process for the development of advanced biomedical devices. By thermally drawing a macroscopic preform, which is meticulously designed and integrated with functional materials, hundreds of meters of multifunctional fibers are produced. These scalable flexible multifunctional fibers are embedded with functionalities such as electrochemical sensing, drug delivery, light delivery, temperature sensing, chemical sensing, pressure sensing, etc. In this review, we summarize the fabrication method of thermally drawn multifunctional fibers and highlight recent developments in thermally drawn fibers for modern biomedical application, including neural interfacing, chemical sensing, tissue engineering, cancer treatment, soft robotics and smart wearables. Finally, we discuss the existing challenges and future directions of this rapidly growing field.

Construction of MXene interlayer conductive ion transport channel by polypyrrole-coated cellulose nanofibers for ultralow voltage high-performance ionic soft actuators

Ionic soft actuators are extensively utilized in soft robotics and intelligent flexible devices due to their low-voltage actuation capability. MXene(Ti3C2Tx) has potential value as an electrode material for ionic soft actuators owing to its high conductivity and large specific surface area. However, the actuation performance of its ionic soft actuator is limited by poor extensibility and low capacitance caused by the stacking effect. Here, a high-performance ionic soft actuator with MXene\\polypyrrole-coated cellulose nanofibers (CNF@PPy) is reported. While gaining high flexibility of the electrode due to the great mechanical property of CNF, the fast conductive transport channel is constructed by doping CNF@PPy between MXene layers, which not only effectively reduces the loss of conductive properties and drastically improves the ion migration rate, but also prevents MXene from stacking and has additional chemical active sites, significantly increasing its ion storage capacity. Consequently, the actuator exhibits excellent actuation performance at the 0.5 V ultralow voltage: 0.79 % bending strain, 6 s rapid response, and 91.03 % high durability after 5 hours. Additionally, the potential for the actuating core of advanced flexible electronic devices is demonstrated by the application of flexible forceps and the flexible electronic eye.

Enhancing electrical conductivity of RuO2 nanosheet-coated films by enlarging the nanosheet area

This study focused on enhancing the electrical conductivity of metal oxide nanosheet films by increasing the size of the nanosheets to promote the electron flow in the desired in-plane direction. We developed a method for increasing the size of RuO2 metal oxide nanosheets, a 2D material, by controlling the heat-treatment process. The size of the RuO2 nanosheets increased from 0.7 to 3.5 μm by modifying the heat-treatment conditions of KxRuO2, which was used as the precursor material. As a consequence, the electrical conductivity of the large-sized-RuO2 nanosheet-coated films was eight times higher than that of their small-sized counterparts. This lower resistance was attributed to the minimal number of contacts required for electron flow; the contact resistance between the nanosheets being higher than the intrinsic resistance. The proposed approach for enhancing the conductivity of metal oxide 2D materials is very promising and is expected to significantly contribute to the development of advanced flexible electronic devices.

Nickel aluminum selenide wrapped by NiCoAl-layered double hydroxide enables a robust structure for supercapacitors

To explore a simple and convenient strategy for the construction of hybrid composites as advanced electrode materials for supercapacitors (SCs), this research realized the construction of nickel − aluminium selenide (NiAlSe)@NiCoAl-layered double hydroxide (NiCoAl-LDH) heterostructure. In-situ hybridization of NiCoAl-LDH nanosheets onto NiAlSe nanoparticles anchored on carbon cloth generates a special core–shell heterostructure, which enhances the exposure of active centers and increases the surface area. The formation of heterogeneous interfaces between NiAlSe and NiCoAl-LDH alters the electronic architecture and accelerates the electron/ion migration. By making full use of the structural benefits and the cooperative effect, the NiAlSe@NiCoAl-LDH composite electrode delivered a large capacitance (Cs) of 1789.2F/g at 1 A/g along with a high retention rate of 94.7 % over 5,000 cycles, which outperforms the bare NiAlSe and NiCoAl-LDH. Meanwhile, the assembled NiAlSe@NiCoAl-LDH hybrid supercapacitor (HSC) attained maximum specific energy (Es) of 71.5 Wh kg−1. This HSC device exhibits superior cyclic durability of 92.1 % after 30,000 cycles. Thereby, this research offers valuable insights into the construction of robust electrode materials for advanced HSC devices.

Boron nitride nanosheets synergized with two‐dimensional micron silver sheets to enhance thermal conductivity and insulation of epoxy resin composites

AbstractWith the rapid progress of the advanced electronic device industry, precision electronic instruments are gradually developing towards miniaturization. In this case, epoxy resin gradually attracts people's attention, but its intrinsic thermal conductivity is not high, and the resulting heat dissipation problem limits the further application of epoxy resin in the field of electronic packaging. Therefore, how to enhance the thermal conductivity of epoxy resins has become an urgent problem in the field of electronic packaging. In this work, BNNS was successfully prepared by stripping h‐BN into a flaky two‐dimensional material, which was added to the epoxy resin as a filler to make the composite material. And on the basis of the above, two‐dimensional micron silver flakes (AgMS) with different mass fractions were added to the composites, and the AgMS/BNNS/EP composites were successfully prepared. When BNNS was 25 wt% and AgMS was 1 wt%, its out‐of‐plane thermal conductivity was enhanced from 0.17 W m−1 K−1 of pure epoxy resin to 0.43 W m−1 K−1. When BNNS was 20 wt% and AgMS was 1 wt%, the breakdown strength was enhanced from 105 kV/mm for pure epoxy to 130 kV/mm. This work provides a new strategy for synthesizing high‐thermal‐conductivity epoxy matrix composites.

Experimental preparation of multiphoton-added coherent states of light

Conditional addition of photons represents a crucial tool for optical quantum state engineering and it forms a fundamental building block of advanced quantum photonic devices. Here we report on experimental implementation of the conditional addition of several photons. We demonstrate the addition of one, two, and three photons to input coherent states with various amplitudes. The resulting highly nonclassical photon-added states are completely characterized with time-domain homodyne tomography, and the nonclassicality of the prepared states is witnessed by the negativity of their Wigner functions. We experimentally demonstrate that the conditional addition of photons realizes approximate noiseless quantum amplification of coherent states with sufficiently large amplitude. We also investigate certification of the stellar rank of the generated multiphoton-added coherent states, which quantifies the non-Gaussian resources required for their preparation. Our results pave the way towards the experimental realization of complex optical quantum operations based on combination of multiple photon additions and subtractions.

Recent developments in MnNiO3@rGO nanohybrid for advanced energy storage devices

Recent developments in MnNiO3@rGO nanohybrid for advanced energy storage devices

Long-Range Ballistic Propagation of 80% Excitonic Fraction Polaritons in a Perovskite Metasurface at Room Temperature.

Exciton-polaritons, hybrid light-matter excitations arising from the strong coupling between excitons in semiconductors and photons in photonic nanostructures, are crucial for exploring the physics of quantum fluids of light and developing all-optical devices. Achieving room temperature propagation of polaritons with a large excitonic fraction is challenging but vital, e.g., for nonlinear light transport. We report on room temperature propagation of exciton-polaritons in a metasurface made from a subwavelength lattice of perovskite pillars. The large Rabi splitting, much greater than the optical phonon energy, decouples the lower polariton band from the phonon bath of the perovskite. These cooled polaritons, in combination with the high group velocity achieved through the metasurface design, enable long-range propagation, exceeding hundreds of micrometers even with an 80% excitonic component. Furthermore, the design of the metasurface introduces an original mechanism for unidirectional propagation through polarization control, suggesting a new avenue for the development of advanced polaritonic devices.

Interlayer Exciton-Phonon Coupling in MoSe2/WSe2 Heterostructures.

Transition metal dichalcogenide heterostructures have garnered strong interest for their robust excitonic properties, mixed light-matter states such as exciton-polaritons, and tailored properties, vital for advanced device engineering. Two-dimensional heterostructures inherit their physics from monolayers with the addition of interlayer processes that have been particularly emphasized for their electronic and optical properties. Here, we demonstrate the interlayer coupling of the MoSe2 phonons to WSe2 excitons in a WSe2/MoSe2 heterostructure using resonant Raman scattering. The WSe2 monolayer induces an interlayer resonance in the Raman cross-section of the MoSe2 A1g phonons. Frozen-phonon calculations within density functional theory reveal a strong deformation-potential coupling between the A1g MoSe2 phonon and the electronic states of the close-by WSe2 layer approaching 20% of the intralayer coupling to the MoSe2 electrons. Understanding the vibrational properties of van der Waals heterostructures requires going beyond the sum of their constituents and considering cross-material coupling.

Unveiling peripheral symmetric acceptors coupling with tetrathienylbenzene core to promote electron transfer dynamics in organic photovoltaics

Non-fullerene organic compounds are promising materials for advanced photovoltaic devices. The photovoltaic and electronic properties of the derivatives (TTBR and TTB1-TTB6) were determined by employing density functional theory (DFT) and time-dependent density functional theory (TD-DFT) analyses using the M06/6-311G(d,p) functional. To enhance the effectiveness of fullerene-free organic photovoltaic cells, modifications were applied to end-capped acceptors by using strong electron-withdrawing moieties. The structural tailoring showed a significant electronic impact for HOMO and LUMO for all chromophores, resulting in decreased band gaps (3.184–2.540 eV). Interestingly, all the designed derivatives exhibited broader absorption spectra in the range of 486.365–605.895 nm in dichloromethane solvent. Among all derivatives, TTB5 was observed to be the promising candidate because of its lowest energy gap (2.54 eV) and binding energy (0.494 eV) values, along with the bathochromic shift (605.895 nm). These chromophores having an A–π–A framework might be considered promising materials for efficient organic cells.