BINA

Mathematical models of voltammetric experiments commonly contain a singular point value for the reversible potential, whereas experimental data for surface-confined redox-active species is often interpreted to contain thermodynamic dispersion, meaning the population of molecules on the electrode possess a distribution of reversible potential values. Large amplitude ramped Fourier Transformed Alternating Current Voltammetry (FTacV), a technique in which a sinusoidal potential-time oscillation is overlaid onto a linear potential-time ramp, is known to provide access to higher order harmonic components that are largely devoid of non-Faradaic current. Initially, a theoretical study reveals that the use of very large amplitude sinusoidal oscillations reduces the apparent effects of thermodynamic dispersion; conversely, frequency can be varied to change the sensitivity of the measurement to kinetic dispersion. Subsequently, FTacV measurements are used to probe a highly thermodynamically dispersed surface-confined ferrocene derivative attached to a glassy carbon electrode, with amplitudes ranging from 25 to 300 mV and low frequency, which minimises the impact of kinetic dispersion. The results from the experimental study validate the theoretical predictions, demonstrating that we can vary the amplitude in FTacV experiments to tune in and out of thermodynamic dispersion.

In this work, we elucidate the crucial role of borate anions ([B(OH)4]-) for the electrocatalytic urea oxidation reaction (UOR) using a nanoporous metallic nickel (NP-Ni) catalyst grown on Si substrates. The UOR activity of the NP-Ni catalyst has been studied at various boric acid (H3BO3) concentrations, demonstrating superior activity at a specific electrolytic composition of 0.5 M KOH, 0.33 M urea, and 50 mM of H3BO3. Based on a wide range of electrochemical techniques, such as, cyclic voltammetry (CV), linear sweep voltammetry (LSV), Pb-anodic deposition, and chronoamperometry (CA), we develop a potential mechanism for the [B(OH)4]--mediated UOR. The high double layer capacitance, surface density of Ni redox sites, and urea oxidation currents, clearly demonstrate the significant impact of [B(OH)4]- during electrolysis. Furthermore, we find that UOR catalyzed by the NP-Ni is controlled by diffusion both in presence and absence of [B(OH)4]-. Finally, a set of physical characterizations, including XPS, SEM, and TEM were performed to correlate the composition and structure of the NP-Ni to the [B(OH)4]--mediated increased UOR activity. The boosted UOR we obtain can open new avenues for treatment of wastewater and assist with environmental remediation.

Temporal optics rises from the equivalence between light diffraction in free space and pulse dispersion in dispersive media, paving the way for the development of temporal devices and applications, such as time-lenses. A Four-wave mixing based time-lens allows single-shot measurements of ultra-short signals in high temporal resolution by imaging signals, and inducing temporal Fourier transform. We introduce a cascade time-lens by utilizing a cascade FWM process within the time-lens. We theoretically develop and experimentally demonstrate the cascade time-lens, and confirm that different cascade orders correspond to different effective temporal systems, leading to measuring in various temporal imaging configurations simultaneously with a single optical setup. This approach can simplify experiments and provide a more comprehensive view of a signal’s phase and temporal structure. Such capabilities are …

Rechargeable Zn-air batteries with near-neutral electrolytes hold promise as cheap, safe and sustainable devices, but they suffer from slow charge kinetics and remain poorly studied. Here we reveal a charge storage mechanism of near-neutral Zn-air batteries that is mediated by H2O2 formation upon cell discharge and its oxidation upon charge. The manifestation of this mechanism strongly depends on the electrolyte composition and positive electrode material, being pronounced when ZnSO4 solutions and carbon nanotubes are employed. Oxidation of dissolved H2O2 is facile, enabling oxygen evolution reaction (OER) at low potentials (~1.5 V vs. Zn2+/Zn) which, in contrast to conventional four-electron OER, does not induce corrosion of carbon electrodes. Facilitation of the H2O2-mediated pathway might therefore be helpful for developing high-performance near-neutral Zn-air batteries.

We investigate a system of Brownian particles weakly bound by attractive parity-symmetric potentials that grow at large distances as , with . The probability density function at long times reaches the Boltzmann-Gibbs equilibrium state, with all moments finite. However, the system's relaxation is not exponential, as is usual for a confining system with a well-defined equilibrium, but instead follows a stretched exponential with exponent . This problem is studied from three perspectives. First, we propose a straightforward and general scaling rate-function solution for . This rate-function, which is an important tool from large deviation theory, also displays anomalous time scaling and a dynamical phase transition. Second, through the eigenfunctions of the Fokker-Planck operator, we obtain, using the WKB method, more complete solutions that reproduce the rate function approach. Finally, we show how the alternative path-integral formalism allows us to recover the same results, with the above rate-function being the solution of the classical Hamilton-Jacobi equation describing the most probable path. Properties such as parity, the role of initial conditions, and the dynamical phase transition are thoroughly studied in all three approaches.

Magnetic ionogels, a category of hybrid materials consisting of magnetic nanoparticles and ionic liquids, have garnered significant interest owing to their remarkable attributes, including tunability, flexibility, and reactivity to external magnetic fields. These materials provide a distinctive amalgamation of the benefits of both magnetic nanoparticles and ionogels, resulting in improved efficacy across many applications. Magnetic ionogels may be readily controlled using magnetic fields, rendering them suitable for drug administration, biosensing, soft robotics, and actuators. The capacity to incorporate these materials into dynamic systems presents novel opportunities for the development of responsive, intelligent materials capable of real-time environmental adaptation. Nonetheless, despite the promising potential of magnetic ionogels, problems persist, including the optimization of the magnetic particle dispersion, the enhancement of the ionogel mechanical strength, and the improvement of the long-term stability. This review presents a comprehensive examination of the syntheses, characteristics, and uses of magnetic ionogels, emphasizing significant breakthroughs and persistent problems within the domain. We examine recent advancements and prospective research trajectories aimed at enhancing the design and efficacy of magnetic ionogels for practical applications across diverse fields, including biomedical uses, sensors, and next-generation actuators. This review seeks to elucidate the present status of magnetic ionogels and their prospective influence on materials science and engineering.

Accurate and continuous monitoring of blood pressure (BP) is essential for cardiovascular health assessment and early detection of potential health issues. Traditional BP measurement methods, such as the inflatable arm cuff, are often inconvenient and do not allow continuous tracking. This study introduces a new optical biosensor for non-invasive BP measurement based on the Iso-Pathlength (IPL) phenomenon, which isolates the scattering effects of light intensity to focus on absorption coefficients, providing a more accurate representation of blood volume changes. The biosensor consists of a single light source and five photodetectors, with one positioned at the IPL point. The sensor was tested on 44 subjects, with measurements taken on the upper arm and compared to reference BP readings from a traditional inflatable cuff monitor. The obtained light intensity was converted into absorption coefficients, from …

Combining Li‐metal anodes (LMAs) with high‐voltage Ni‐rich layered‐oxide cathodes is a promising approach to realizing high‐energy‐density Li secondary batteries. However, these systems experience severe capacity decay due to structural degradation of high‐voltage cathodes and side reactions of electrolyte solutions with both electrodes. Herein, the use of multi‐functional additives in fluoroethylene carbonate‐based electrolyte solutions that enable the operation of successfully rechargeable high‐voltage (4.5 V) Li‐metal batteries (LMBs) with high areal capacity (>4 mAh cm−2) are reported. Customized electrolyte solutions are pivotal in passivating the electrodes, minimizing microcrack formation, and ensuring that current is uniformly distributed within cathode particles. The developed electrolyte solution protects the LMA by forming a very stable and effective solid–electrolyte interphase. Together with the …

The formation of Li6PS5Cl argyrodite solid electrolyte pellets typically involves compaction at ∼20 °C and hundreds of megapascal of pressure, and the resulting pellets usually need >10 MPa operating pressure to achieve ionic conductivities >1 mS cm–1 at 25 °C and/or sputtered metal electrodes. This work demonstrates a key advance achieved with pellet fabrication at 150 °C and 300 MPa with foil electrodes: >2 mS cm–1 ionic conductivity at 20 °C with <1 MPa operating pressure. Scanning electron microscopy reveals fused grains present in samples pressed at 150 °C but not in those at 20 °C. X-ray photoelectron spectroscopy and diffraction analysis show no significant difference in crystal structure or surface composition between 150 and 20 °C pressed samples, and the pellet densities are nearly identical. The ionic conductivity of 150 °C pressed samples is nearly invariant with operating pressure, while that …

Communication of cancer cells with immune cells can inhibit or promote tumor proliferation. However, immune–tumor interactions in cancer tissues remain largely uncharacterized. A direct quantification of cell–cell interactions between individual immune and tumor cells can be obtained via in situ approaches, which use imaging to assess the identity and location of expressed genes. We recently developed a technology, termed expansion sequencing, which allows in situ sequencing of RNA molecules with super-resolution. Here, we show that super-resolved in situ sequencing can be used to quantify immune–tumor cell–cell interactions inside patients' biopsies, which might be utilized to predict response to immunotherapy drugs.

Rechargeable magnesium metal batteries (RMBs) represent a promising sustainable energy storage technology, complementary to lithium-ion and sodium-ion batteries due to their superior volumetric energy density, cost-effectiveness, and safety. However, their widespread adoption is hindered by limited electrolyte options due to the formation of Mg ion-insulating surface films that cannot behave as solid-electrolyte-interphases. Here, after considering the binding affinity with Mg²⁺ and steric hindrance, we report a single-solvent system based on commercial aminoacetaldehyde dimethyl acetal (ADMA). Our system effectively forms a Mg ion-conducting interphase and enhances the Mg plating-stripping efficiency, without severe corrosion. The average Coulombic efficiency is 97.3% over 500 hours upon galvanostatic cycling in Mg‖stainless steel cells at cycling conditions of 0.5 mA cm⁻² and 0.5 mAh cm⁻², along with capacity retention of 90.3% and 99.2% for 250 and 300 cycles in Mg‖Mo₆S₈ and Mg‖Tellurium full-cells, respectively. This study indicates that high-performance practical RMBs are achievable through solvation structure engineering with commercially available solvents and salts.

Using pluripotent stem cells from patients, it is now possible to create three-dimensional (3D) brain organoids that can be used in the study of neurological disorders. However, measuring the molecular content of 3D organoids is still a challenge, limiting the usability of organoids. Here we demonstrate the first multiplexed super-resolved characterization of intact brain organoids, using a combination of expansion microscopy, serial protein staining, expansion sequencing and enhanced super-resolution radial fluctuations. Overall, without special hardware or dyes, we obtain resolution improvement of ~10x, and perform highly multiplexed and super-resolved RNA and protein interrogation of intact brain organoids.

Molecular characterization of brain tissues using optical methods present a problem of scale: brain tissues are intrinsically three-dimensional structures, with thickness of at least hundreds of micrometers; but nanoscale interrogation is needed to characterize molecules within neurites and synapses. Additionally, multiplexed interrogation of molecules is needed to characterize cell types and states inside brain tissues, and to detect deficiencies in neurological conditions. Currently, multiplexed imaging of molecules inside brain tissues is limited to thin sections, and almost impossible with super-resolution. Here we demonstrate multiplexed super-resolved characterization of thick brain tissues: complete fruit fly brain, human brain organoids, and mouse cortex.

We developed an optical communication system based on folded mirror for nano-sat. Nano-sat is too small to have big mirrors; therefore, it is challenging to have a wide bandwidth communication system over thousands of km. We overcome this challenge by using a folded mirror and compensating for misalignments with electronic components.

In this proceeding, we expand upon our recent work on the temporal Aharonov-Bohm (AB) effect, focusing on the joint temporal function (JSF) analysis to enhance the sensitivity and understanding of the system’s performance. Our original paper demonstrated the existence of a temporal analog of the Aharonov-Bohm effect using entangled photons and a temporal SU(1,1) interferometer. Here, we provide a more detailed exploration of the JSF, highlighting its role in improving signal-to-noise ratios (SNR) and its impact on measuring fast phase changes with enhanced temporal resolution. By leveraging the quantum properties of the system and utilizing the JSF between the signal and idler beams, we show that this approach allows for unprecedented sensitivity in detecting temporal phase shifts. This proceeding will also discuss how the JSF contributes to the interferometer’s ability to resolve femto-second dynamics …

Electrode–electrolyte interphases are critical determinants of the reversibility and longevity of lithium (Li)-metal batteries (LMBs). However, upon cycling, the inherently delicate interphases, formed from electrolyte decomposition, become vulnerable to chemomechanical degradation and corrosion, resulting in rapid capacity loss and thus short battery life. Here, we present a comprehensive analysis of the complex interplay between the thermodynamic and kinetic properties of interphases on Li-metal anodes, providing insights into interphase design to address these challenges. Direct measurements of ion-transport kinetics across various electrolyte chemistries reveal that interphases with high Li-ion mobility are essential for achieving dense Li deposits. Conversely, sluggish ion transport generates high-surface-area Li deposits that induce Li random stripping and the accumulation of isolated Li deposits. Surprisingly …