Methanol decomposition is a benchmark reaction for understanding surface-mediated redox chemistry and photocatalytic processes on oxide materials. While its mechanism on TiO2 has been extensively studied under ultra-high-vacuum (UHV) conditions, the reaction pathway under ambient, liquid-phase environments remains largely unexplored. Here, we investigate the photocatalytic decomposition of methanol on rutile TiO2(110) following direct adsorption from liquid solution by combining surface-sensitive sum frequency generation (SFG) spectroscopy with density functional theory (DFT) calculations. SFG measurements identify methoxy as the dominant surface species under these conditions. DFT calculations reveal that cooperative hydrogen-bonding interactions stabilize both the transition state and the dissociated configuration, leading to a systematic reduction in activation barriers. Concurrently, localized excess charge facilitates proton transfer through dynamic redistribution along the reaction coordinate, thereby lowering the barrier for O─H bond cleavage and stabilizing reaction intermediates. Under resonant bandgap excitation, methoxy undergoes structural reorientation followed by oxidation to form a stable surface hydroxymethyl species. DFT calculations further demonstrate that interfacial water and hydroxyl groups stabilize localized charge carriers, reduce activation barriers, and promote proton-coupled electron transfer. These findings provide molecular-level insight into the role of interfacial hydration in governing photocatalytic reaction pathways at oxide-liquid interfaces.

A solid synthetic pathway for the localized formation of vertically aligned and well-distributed individual gold nanoparticles (AuNPs) in transparent ion-track-etched polyvinylidene fluoride membranes is herein reported. After a successful preconcentration of the Au-(III) precursor within the functionalized cylindrical nanochannels of these membranes, i.e., ion-track-etched radiografted with poly-(4-vinylpyridine) (P4VP), a Au-(IIII)-to-Au(0) chemical reduction was performed to in situ grow AuNPs inside the nanopores. Four classical reducing agents [ascorbic acid, hydroquinone, sodium citrate, and sodium borohydride (NaBH4)] were studied, which led, at first glance, to similar composites. The reducing power of each reducing agent has been shown to affect the AuNP nucleation and growth processes. At room temperature, the reduction led to the synthesis of well-dispersed AuNPs along the whole pore length, with the exception of sodium citrate, which was found to be too weak to reduce efficiently the gold precursor. When energy was provided to the system by operating the reaction at 70 °C, the reduction was boosted and the synthesis with sodium citrate gave similar results to those obtained with the other reducing agents at 20 °C, i.e., well-distributed AuNPs of around 30 nm of mean size. Increasing the number of reduction cycles resulted in an increase in AuNP size and, in the case of hydroquinone, in the elongation of the gold nanocrystals. This phenomenon was attributed to template-assisted AuNP growth in the nanopores. Despite the low amount of gold in the material (less than 0.2 %), the alignment of individual AuNPs all along the high aspect ratio nanopores (50:10,000) had a significant effect on the optical properties of the whole material, with the appearance of plasmonic properties for the nanocomposite membranes (λplasmon around 530 nm) and a further decrease of the effective refractive index of the nanoporous membranes.

This work presents the heterogenization of phenothiazine-based photocatalysts onto carbon nanotubes (CNTs) through mechanical interlocking. Two different photocatalysts featuring a phenothiazine core were synthesized. Both derivatives were successfully clipped onto single-walled carbon nanotubes (SWNTs) of different diameters by means of ring-closing metathesis. Comprehensive characterization of the resulting mechanically interlocked carbon nanotubes (MINTs) bearing the photocatalysts, using spectroscopic, microscopic, and computational techniques, confirms the effectiveness of the procedure, achieving a functionalization degree of 10%-14% with photoactive materials. These photocatalyst-MINT hybrids were subsequently evaluated in the photocatalytic borylation of aryl halides. Both MINT materials exhibited similar or improved performance compared to their homogeneous counterparts, while also demonstrating enhanced substrate tolerance, recyclability, and robustness. Furthermore, the mechanism of the photocatalytic reaction mediated by the MINT materials was investigated through both experimental and computational studies. The results highlight the importance of electronic communication between the nanotube and the molecular photocatalyst for achieving the observed catalytic behavior.

Borophene, a two-dimensional (2D) boron sheet, has recently gained considerable attention as a postgraphene material owing to its unique properties, such as intrinsic metallic character, lightest element monolayer structure, and high-frequency phonons. These features, together with its theoretically predicted high density of states, make borophene an excellent platform for investigating various quantum phenomena. However, the realization of emergent phenomena is hindered by fabrication challenges and inherently weak electronic correlations within the s and p electron system. Here, we demonstrate a strongly correlated 2D electronic state derived from a honeycomb boron lattice exposed at the surface of ternary boride LaRh3B2. Using angle-resolved photoemission spectroscopy, we uncover the extended saddle-point van Hove singularity near the Fermi level, which is linked to the substantial lattice expansion and many-body interaction. Moreover, scanning tunneling microscopy reveals the electronic nematicity, which likely originates from the saddle-point instability. Our findings open a pathway to exploring the exotic correlated phenomena in boron-based 2D systems.

The extracellular matrix (ECM) is a major regulator of cellular behavior, fate, and various mechanisms underlying homeostasis, development, and disease. Biophysical and biochemical properties of the ECM are known to affect three-dimensional (3D) cellular behavior and phenotype that regulate a wide range of pathological conditions. Tunable biomimetic hydrogels are extensively employed to investigate cell-matrix interactions in defined 3D microenvironments. However, the dynamics of these interactions in complex coupled multiparametric microenvironments has been relatively less studied. This study aims to provide a framework for correlating cellular and nuclear behavior as a function of specific matrix properties (adhesivity, degradability, porosity, and stiffness) in a biosynthetic hydrogel system with varying crosslinking mechanisms. Poly(ethylene glycol diacrylate)-fibrinogen (PF)-based hydrogels were fabricated with varying crosslinking profiles, resulting in a series of hydrogels with varying matrix properties. NIH3T3 mouse fibroblasts were cultured in 3D and their matrix-associated morphological responses were studied over time. Matrix adhesivity and degradability (collectively termed 'matrix permissiveness') were found to be the most influential parameters regulating cell and nuclear behavior. Cells in permissive matrices displayed high viability, high cell density, increased spreading and protrusivity, and large elongated nuclei. Cells in restrictive matrices displayed reduced viability and lower cell density, rounded morphology, lower spreading, and smaller rounded nuclei. Cell confinement and nuclear confinement determined from various morphological features were correlated to matrix permissiveness. Overall, this study provides insights into regulation of cellular and nuclear behavior through modulation of matrix properties which could be used for future applications in various disease contexts. STATEMENT OF SIGNIFICANCE: Biomimetic engineered hydrogels are commonly used to support three-dimensional (3D) tissue-level behavior to recapitulate various developmental processes and disease states. Specific biophysical and biochemical cues in the engineered microenvironment can be used to control cellular behavior, morphology, and function, thereby providing mechanistic insights into cell-matrix interactions. This study assesses the variations in the cellular and nuclear features of fibroblasts encapsulated in 3D hydrogel matrices with varying crosslinking mechanisms. Our results reveal the combinatorial role of matrix adhesivity and degradability in regulating cellular and nuclear confinement of fibroblasts in 3D restrictive microenvironments. Overall, these matrix guiding principles can be implemented in the future to design tunable biomimetic matrices to modulate cell state, behavior, and function.

CubeSats have emerged as an enabling technology for a new generation of space missions, offering relatively low cost and rapid development opportunities for scientific, educational, and technology demonstration. The reliable operation of a CubeSat depends critically on its electrical power system (EPS), which serves as the primary energy backbone for all onboard subsystems and payloads. Several studies have indicated that EPS as a subsystem is most susceptible to failure in the satellite missions, as it is under tight power, volume, and reliability constraints exposed to harsh and variable orbital conditions. In this context, this paper proposes the design, hardware implementation and experimental validation of an autonomous EPS architecture to enhance the operational lifetime of CubeSats. The proposed EPS autonomously manages energy to deal with solar irradiance variations in the low earth orbit (LEO). It combines maximum power point tracking (MPPT), battery management system (BMS), regulated power distribution and sensor based telemetry based on a microcontroller unit (MCU) controlled system. A real time decision making algorithm autonomously monitors the photovoltaic (PV) array voltage. The supervisory algorithm implements a three mode graduated control strategy, i.e. normal, moderate, and power-down. It is governed by two discrete PV voltage thresholds, enabling more precise and graduated load management compared to binary single threshold schemes reported in prior work. When nominal irradiance level is regained, the system returns autonomously to desired operational mode with no interference needed from the ground station. The modular design of the system allows to upgrade its components easily without the need to redevelop entire architecture. A detailed power budget analysis yields a total system load of 1,460mW, divided between telemetry (22mW), payload (1,400mW) and communication subsystems (38mW). The deployed EPS uses a Li-ion 3-cell battery pack (11.1V, each cell 1,800mAh) and PV panels of (12V, 2,100mW). Experimental tests validate the acquisition of data from various sensors and importantly accurate mode transition from normal to power down mode and vice-versa under fluctuating irradiance conditions. Furthermore, dynamic experiments involving controlled variation of PV voltage are also conducted to evaluate both degradation and recovery behavior of the system. The results demonstrate stable, repeatable, and threshold consistent mode transitions under varying input power scenarios. The results collectively demonstrate that autonomous mode transition and load management can be achieved using low cost commercial off the shelf components (COTS), making the proposed EPS a practical, reproducible, and scalable testbed for academic and small mission CubeSat platforms.

Like most chiroptical spectroscopy techniques, photoelectron circular dichroism (PECD), that is, the forward-backward asymmetry in the angular distribution of the electron resulting from the ionization of a chiral molecule by a circularly polarized light, is very sensitive to structural changes, in particular conformational isomerism. Moreover, because of the large associated asymmetries (up to a few 10's of %), PECD is uniquely adapted to gas-phase studies of flexible chiral molecules and exists, for the case of valence-shell, in several variants relying upon one vaccum-ulraviolet (VUV) photon or multiple-photon ionization. We describe here recent advances in PECD spectroscopy that make this method conformer-selective. In addition to partial population selection in one-photon PECD, two-photon PECD resting on a resonance-enhanced ionization scheme allows complete conformer selection, as long as the studied system displays an electronic transition in the near UV. These experiments thus provide a direct connection between structures (conformations) and chirality (PECD), which both influence phenomena such as molecular recognition. The low temperature achieved under supersonic expansion conditions and the narrow-band nanosecond laser used allow deciphering conformers with very similar structures, like ring-inversion conformers or those related to a hydrogen bond, or even distinguishing the lone electron pairs in a diastereotopic molecule.

We present a detailed ab initio investigation of the Cu L-edge X-ray photoelectron spectroscopy (XPS) spectrum in D4h copper phthalocyanine (CuPc). Spin-orbit coupling is treated with the Breit-Pauli Hamiltonian, and transition intensities are computed using the Löwdin formalism within the sudden approximation, accounting for nonorthogonality between initial and final-state wave functions. The nonorthogonal Löwdin determinant approach accurately reproduces experimental intensities, while orbital analysis highlights the charge-transfer and orbital-reorganization processes underlying the excitations. These results provide a quantitative and physically transparent interpretation of the Cu L-edge XPS spectrum, clarifying the distinct ligand and metal-centered character of the main and satellite excitations. The main L2,3 peak is dominated by a ligand-centered excitation (Ligand (b1g) → a1u), whereas the shakeup satellite arises primarily from metal-to-ligand excitations (Metal (Cu 3d) → a1u).

We report on a joint experimental and theoretical investigation of the metal 2p X-ray photoelectron spectra of transition-metal phthalocyanines MnPc, FePc, and CoPc. Using a multiconfigurational approach including spin-orbit coupling, we obtain nearly quantitative agreement with experiment. In all investigated systems, we found an unexpected and robust physical effect induced by core ionization, namely a drastic reorganization of the valence electronic structure. This reorganization is characterized by a pronounced stabilization of doubly excited ligand-to-metal charge-transfer configurations, which become energetically favored in the final states. This ionization-induced double charge transfer is found to be common to all metallophthalocyanines studied. Furthermore, we identify a nearly linear correlation between the stabilization energies obtained from restricted active space configuration interaction (RAS-CI) calculations and a simple hydrogenic/Slater screening estimate, providing an intuitive and practical descriptor to assess when such charge-transfer states are expected to dominate after core ionization.

To analyze Isosorbide Mononitrate in human plasma, a highly sensitive and accurate LC–MS/MS bioanalytical method was developed and validated using Isosorbide mononitrate-[13]C6 as the internal standard. Validate a suitable analytical method for the estimation of unknown drug concentrations in plasma. It can be used for the quantitation of isosorbide mononitrate in K2EDTA human plasma for bioequivalence and bioavailability studies. The method was found to be specific, sensitive, linear, precise, accurate, and reproducible for the extraction and analysis of isosorbide mononitrate in K2EDTA human plasma samples over the investigated concentration range of 5.000 ng/mL to 1800.000 ng/mL using a processing volume of 0.100 mL. Chromatographic separation was achieved using a 2 mM ammonium acetate (acidified) mobile phase with acetonitrile containing 0.1% acetic acid in a ratio of 55:45 (v/v) at a flow rate of 0.5 mL/min. Detection was carried out using multiple reaction monitoring with transitions (m/z) of 249.90 → 59.00 for isosorbide mononitrate and 255.90 → 58.90 for the internal standard. The analytes were detected using tandem mass spectrometry (LC–MS/MS). The proposed method was comprehensively validated in terms of linearity, accuracy, precision, specificity, sensitivity, recovery, and stability, with results meeting the acceptance criteria. The developed and validated method was found to be simpler, faster, more specific, precise, and cost-effective compared with previously reported methods.

In advanced robot systems, monitoring the health of key components such as bearings in the transmission system is crucial for achieving reliable autonomous operation. However, there are still challenges in accurately diagnosing bearing faults under dynamic and noisy conditions.

We investigate the electronic structure of two dithienylethene (DTE) molecular photoswitches, BTF6 and PTF6, in the gas phase by combining valence photoelectron spectroscopy (PES), x-ray photoelectron spectroscopy, and the near-edge x-ray absorption fine structure. DTEs have attracted significant attention due to their high photoisomerization quantum yield, fatigue resistance, and thermal irreversibility, which underpin applications ranging from molecular machines to photoswitchable biomolecules. Supported by first-principles simulations, our analysis elucidates how the different extent of π-conjugation, arising from the distinct thiophene/benzothiophene subunits, manifests across the various spectroscopic observables. By comparing the calculated signatures of the open- and closed-ring isomers, we further assess the sensitivity of each probe to the structural changes associated with photoinduced cyclization. Overall, these results deliver a detailed picture of the intrinsic electronic properties of DTEs in the gas phase and provide a robust basis for future time-resolved studies of their ultrafast photoisomerization dynamics.

Identifying systems composed of earth-abundant elements capable of photoinduced electron-transfer represents a major breakthrough for the development of sustainable photocatalytic processes. Herein, we demonstrate that octahedral tungsten-halide clusters constitute a promising new class of robust photosensitizers, owing to their exceptional chemical stability, intense luminescence, and long-lived triplet excited states. Upon irradiation in aqueous solution, these species transfer an electron to polyoxometalates (POMs), well-known molecular catalysts capable of multielectron redox chemistry. More specifically, we investigate the photophysical properties of supramolecular systems combining the cluster-based motif [{W6I[i]8}Cl[a]6][2-] and a series of archetypal POMs ([PW12O40][3-], [SiW12O40][4-], [BW12O40][5-], [P2W18O62][6-]) as electron-acceptor units, in the presence of γ-cyclodextrin (γ-CD), which acts as both a supramolecular assembly scaffold and a stabilizing agent. The photoinduced electron-transfer process was investigated using steady-state and time-resolved optical spectroscopy, complemented by spectro-electrochemical measurements, which unambiguously confirm electron transfer from the excited cluster to the POMs. Furthermore, we demonstrate that both the ionic charge of the POMs and the presence of γ-CD significantly influence the efficiency of the process. This work highlights the dual role of γ-CD, which facilitates the association of two negatively charged inorganic units and stabilizes the charge-separated state by maintaining an appropriate spatial arrangement within the supramolecular assembly.