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Selectivity of the electric field direction plays a vital role in modulating the phonon characteristics as well as electrical properties in low-dimensional materials. A comprehensive study on the effects of the direction-dependent electric field on MoS2 sample is reported herewith. The field-induced changes in the phonon characteristics and electronic band structure have been systematically investigated based on field responsive Raman and photoluminescence measurements. The atomistic insights obtained from density functional theory calculations have been correlated with the experimental observations to elucidate the underlying mechanism. The applied transverse electric field is found to be significantly more efficacious than the electric field applied vertically in altering the phonon signatures and bandgap in MoS2, where the electrostrictive response is found to arise from the field-induced alteration in metal–chalcogen interatomic bonds. [ABSTRACT FROM AUTHOR]

The non-oxide 2D materials have garnered considerable interest due to their potential utilization as photocatalysts, which offer a superior substitute to metal-oxide-based photocatalysts. This study investigates the impact of the dielectric environment on the size and binding energy of excitons in atomically thin, experimentally synthesized semiconducting monolayers [XPSe3, X = (Cd, Zn)] to address the critical problem of electron–hole recombination, which significantly hinders the efficiency of most photocatalysts. We employ a precise non-hydrogenic model surpassing the hydrogenic-based Mott–Wannier model. Our findings are among the first few demonstrations of an increase in exciton size (and decrease in exciton binding energy) as environmental screening increases. These findings have implications for photocatalytic water splitting and are not limited to metal phosphorus trichalcogenides, but can be applied to other classes of 2D materials as well. This work also compares metal-oxide photocatalysts, which have been the focus of much research over the past five decades, to non-oxide-based metal phosphorus trichalcogenide photocatalysts, which offer a superior alternative due to their ability to address issues such as light-harvesting inability in the visible spectrum and unwanted charge recombination centres. Furthermore, the implications of this study extend beyond photocatalysts and are significant for the design and development of next-generation optoelectronic devices that incorporate excitonic processes, such as solar cells, photodetectors, LEDs, etc. [ABSTRACT FROM AUTHOR]

Bimetallic nanoclusters (NCs) have emerged as a new class of luminescent materials for potential applications in sensing, bio-imaging, and light-emitting diodes (LEDs). Here, we have synthesized gold–copper bimetallic nanoclusters (AuCu NCs) using a one-step co-reduction method and tuned the emission wavelength from 520 nm to 620 nm by changing the [Cu2+]/[Au3+] molar ratio. The quantum yield (QY) increases from 6% to 13% upon incorporation of the Cu atom in the Au NCs. MALDI-TOF mass spectrometric analysis reveals that the composition of the Au NCs is Au6(MPA)5, and the bimetallic nanocluster is Au4Cu2(MPA)5, where 3-mercaptopropionic acid (MPA) is used as the capping ligand. Furthermore, we investigated the optimized structures of the as-synthesized NCs using density functional theory (DFT) along with analysis of the preferable adsorption sites using Fukui functions. We report the HOMO–LUMO gap, which is consistent with the experimentally observed red shift in the UV-Vis absorption features of the Au NCs upon copper doping. XPS studies suggest the formation of intermixing of states between the 5d orbitals of Au and the 3d orbitals of Cu in the AuCu NCs after incorporating Cu atoms into the Au NCs, which is corroborated by the DFT calculations on electronic charge transfer from the Cu to the Au atom in the NCs. The coupling between Au(I) and Cu(I) facilitates the formation of a low-lying mixed Au(I)–Cu(I) energy state. This study elaborates on the impact of Cu doping on the excited-state relaxation dynamics of AuCu NCs. [ABSTRACT FROM AUTHOR]

The present study investigates the efficiency of using sand crumb rubber mixture for vibration isolation and its prediction using machine learning. Safe disposal of waste rubber from tire industries is a matter of concern due to its detrimental effects. A two-dimensional finite element (FE) analysis was performed in ABAQUS, considering a strip foundation as the source of vibration. The effectiveness of the screening was evaluated by calculating the Amplitude Reduction Factor (Arf) for open and infilled trench (OT and IFT) for different trench geometry (distance from the source, depth and width). In previous studies, modelling such screening problems has mostly been accomplished through regression models. The present study explored the Support Vector Regression (SVR) model since machine learning excels in modelling complex behaviours. The SVR model's optimum parameters were successfully determined by performing a grid search and selecting the best model using the Preferential Ranking Organization Method for Enrichment Evaluation (PROMETHEE) technique. [ABSTRACT FROM AUTHOR]

A density functional framework has been used to explore the geometrical stability and electronic properties of phosphorene sheet. The non-equilibrium Green's function approach has also been utilized to calculate the quantum transport properties. Phosphorene sheet has been focused under the influence of substitutional doping, where selected dopants are Si, Ge, S and Se, along with variation in the concentration of dopant is considered, i.e. 1.265% (Si1, Ge1, S1, Se1) and 2.564% (Si1, Ge1, S1, Se1). The geometrical structure and bandgap followed by density of states are also evaluated. The quantum transport properties are analysed by applying 2-V biased voltage. The current shows non-linear behaviour up to 0.75 V for each doped phosphorene sheet, which has been explored in detail, whereas Ge2 shows a most prompt rise in current, that is 62 µA. Finally, the optical properties have been reckoned by determining reflectivity and absorption coefficient. Our findings have great applications in the field of two-dimensional-based optoelectronics application. [ABSTRACT FROM AUTHOR]