The investigation of the nonlinear optical (NLO) properties of polyaniline (PANI) and polyaniline doped with multi-walled carbon nanotube (PANI-MWCNT) in both solution and film forms was conducted using the open-aperture z-scan approach. A Q-switched resonant Nd: YAG laser with a wavelength of 532nm and two different fluences was utilized in this study. Based on the z-scan experiments, it was observed that the NLO behaviour of PANI and PANI-MWCNT composites exhibited a transition from reverse saturable absorption (RSA) to saturable absorption (SA) when the samples changed from a liquid to a film state. Two photon absorption (TPA) and thermally induced nonlinear scattering are the main mechanisms behind the RSA behaviour of the materials in solution form. The reason for SA behaviour of these materials in film form is attributed as the ground-state free electron bleaching in the conduction band due to the increased laser intensity. Due to increased structural disorder and the defect states or trap levels created by the dopants in the PANI system, the NLO properties of the PANI-MWCNT composite in both solution and film forms have significantly improved compared to those of pure PANI. Urbach tail analysis and carbon cluster determination revealed the presence of defect states in the composites system. The composite between PANI and MWCNT was verified using Fourier transform infrared (FTIR) spectroscopy. The functional elements present in the composites are verified by X-ray photoelectron spectroscopy. The NLO parameters of the samples, viz., the nonlinear absorption coefficient (β), the imaginary part of the nonlinear, and susceptibility χi(3) the figure of merit (FOM) of PANI-MWCNT, exhibited a notable enhancement in their values over PANI. Moreover, the PANI-MWCNT film demonstrated superior SA performance and the PANI-MWCNT solution demonstrated better OL performance compared to that of the PANI film and solution respectively. Also the effects of dopant induced structural modifications and lattice disorder on the NLO behaviour of these materials are correlated with the obtained NLO parameters. The tunable NLO properties accomplished by controlling the structural phase and dopant-induced defects enhance the possibility of these nanostructures for applications in optical limiting, optical switching, optical modulation, optical pulse compression and laser pulse narrowing.

The development of multi-functional hydrogels is necessary to meet the needs of flexible sensors in different application scenarios. A conductive hydrogel with high toughness, adhesion, self-healing and anti-freezing properties was prepared. The hydrogel was synthesized by in-situ polymerization of acrylic acid in glycerol hydrate solution system of gelatin and aluminum ion, and then cryogenically refrigerated. After low temperature treatment, the triple helix structure produced by the self-assembly of the gelatin in the hydrogel increases the cross-linking density of the hydrogel, and forms a double network with polyacrylic acid to improve its mechanical properties (stress up to 85.7 kPa, strain up to 1428 %). In addition, this triple helix structure can dissociate and recombine at different temperatures, and interact with other dynamic bonds (hydrogen bonds, Al3+ coordination) in the system, so that the hydrogel has excellent self-healing ability (healing rate up to 86.8 %). Because the system contains a large number of -OH, -NH2 and -COOH groups, it can adhere to the surface of various materials through hydrogen bonding. The free Al3+ makes the hydrogel obtain good electrical conductivity and strain sensitivity (GF=3.01), and the strain sensor assembled by it has a stable and accurate monitoring effect on the fine movements of human body such as various joint movements and pronunciation. Additionally, the presence of glycerol provides anti-freezing properties, ensuring flexibility and electrical conductivity even at low temperatures (-20 ◦C). This hydrogel is a promising candidate for intelligent wearable devices in extreme environments such as snow and ice sports.

The pace of research discoveries depends heavily on the substances employed and micro technologies. However, fascination with graphene and similar two-dimensional materials is growing due to the anticipated significant benefits in terms of both performance enhancement and atomic-scale growth. The prospects for integrating graphene, microswimmers, and microfluidic systems have become more apparent with the advent of new biomedical applications. With excellent mechanical characteristics, electrical and thermal conductivity, and biocompatibility, the material has the potential to revolutionize the delivery of next-generation innovative biomedical devices. This article investigates how these various systems might be coupled in novel ways, for as by imbuing microswimmers with graphene characteristics and using their mobility and the regulated fluidic conditions of microfluidics to achieve new therapeutic and diagnostic goals. Such applications include targeted drug delivery, non-invasive diagnosis, and environmental monitoring, in which the buoyancy of the microswimmer aids in relatively good movement with the fluidic media, aided by the microchannel structure and the microswimmer, which moves precisely through several micro channels. We delve into the challenges, opportunities, and the role of graphene in shaping biological domains relevant to the development of microswimmers and microfluidics. Through this exploration, we aim to uncover pathways for further innovation in biomedical research and application.Top of Form

We have investigated the structural, mechanical, lattice dynamics, electronic, optical and thermal properties of Ti2PTe2 chalcogenide using density functional theory for the first time. The optimized unit cell parameters show excellent agreement with experimental values. The stability of Ti2PTe2 is confirmed by thermodynamic, mechanical, and dynamical stability criteria. The material exhibits softness, machinability, and brittleness, making it suitable for applications requiring ease of fabrication and damage tolerance. The compound is elastically and optically anisotropic. Its electronic properties reveal a metallic nature, characterized by a mix of covalent, ionic, and metallic bonding. Its ultra-low thermal conductivity suggests Ti2PTe2 is a promising candidate for thermal barrier coatings (TBCs). Additionally, its strong UV absorption makes it useful for UV detectors, anti-reflective coatings, and protection against photo-disintegration. With a high static refractive index and impressive reflectivity, Ti2PTe2 also holds potential for advanced display technologies and solar heating reduction. We believe this study will inspire further research, expanding the material’s application potential beyond traditional boundaries.

The classic Hall-Petch model effectively captures the relationship between strength and layer thickness for thicknesses above 100 nm, while the constrained layer slip (CLS) model provides a better prediction for thicknesses below 100 nm. Nonetheless, the precision of the current CLS model is insufficient, especially for structures with FCC/HCP interfaces, which limits the development of lightweight composites such as Al/Mg. To address this gap, this study uses molecular dynamics (MD) simulations to explore the CLS mechanism under compression in Al/Mg composites. We propose a novel dual-mode CLS model aimed at enhancing the accuracy of stress predictions across a wide range of layer thicknesses and various slip angles. Our findings indicate that with decreasing layer thickness and the loss of lattice structure, the FCC/HCP interface becomes unstable and exhibits reduced strength when the layer thickness falls below 26.7 nm. Moreover, as the slip angle rises from 0° to 75°, the improved interface compatibility aids in the initiation of basal slip in the Mg layer. This triggers a migration of dislocations from the Al side to the Mg side, thereby altering the dominant CLS mechanism. This work is expected to accelerate the development of Al/Mg composites and other similar FCC/HCP composite systems.

Lamella is a unique microstructure in matters that possesses special properties. The formation and evolution of lamellar microstructures are crucial for achieving super abilities, while the mechanisms of lamellar formation and evolution at the nanoscale are unclear. Driving by the interesting while uncovered micromechanism in lamellar microstructure evolution, we performed the phase-field simulation and experiment to investigate the multiple splitting behaviors of lamellar Ti-Al alloys. The splitting mode of lamella is discovered, inner splitting (IS) and outside splitting (OS). The originations of splitting are found to come from the high interfacial energy of step-like interface between γ variants for the IS, and the stress concentration at α2/γ interface drives step-like interface for the OS. The lamellar splitting is complied with the energy change in matter, decreasing in total free energy and elastic energy, while increasing in interfacial energy. These findings provide the new mechanisms of internal lamellar interface breaking driven by the interfacial energy. Therefrom, the expected matter features will be achieved by the strategy of microstructure modulation and optimization.

Sulfide solid electrolytes are promising materials for next-generation all-solid-state lithium batteries due to their high ionic conductivity, mechanical properties, and compatibility with advanced electrodes like lithium metal. Recent advancements have focused on optimizing synthesis techniques, including both solid-phase and liquid-phase methods, alongside strategic doping modifications that enhance ionic conductivity and improve chemical stability. Despite these improvements, challenges remain, particularly in stabilizing interfaces between sulfide solid electrolytes and electrodes, as chemical reactivity leads to resistive layers and reduced battery performance. Efforts to address these challenges involve protective coatings, surface engineering, and advanced structural modifications. Additionally, sulfide solid electrolytes face environmental sensitivity, with exposure to air and moisture leading to degradation. To counter this, strategies such as hybrid electrolyte systems and surface treatments are being investigated to ensure long-term stability under various conditions. This review summarizes recent developments in sulfide solid electrolytes synthesis, doping modification, and interface engineering, while outlining future directions needed for the successful commercialization of all-solid-state lithium batteries, positioning sulfide-based electrolytes as key components for advancing battery safety, efficiency, and energy density.

Lewis base additives typically undergo interactions with SnI2 to achieve effective defect passivation in lead-free perovskite films. In this work, the thiophene ring in 2-thiophenethylammonium chloride (TEACl) has coordination interactions with Sn2+ and the -NH3+ therein forms hydrogen bonds with I-. This facilitates the deposition of homogeneous and dense films with fewer defects during crystallization process. Otherwise, 2-pyridinethylammonium chloride (AEPCl) gives poorly perovskite films with high defect density because of the overly strong interaction with SnI2. As a result, the average photoluminescence life time of TEACl-passivated perovskite film was substantially increased to 22.04 ns, compared with the control film (5.15 ns) and the AEPCl-passivated film (3.55 ns). Ultimately, the target solar cell with TEACl passivation presented a power conversion efficiency of 13.24% and excellent shelf-stand stability with a 90% retaining of initial efficiency after 2000 h of aging in N2 atmosphere. This work sheds new light on the structural tailoring of Lewis base passivators for efficient defect passivation in lead-free tin halide perovskites.

The photogalvanic cells presented in this research work are energy devices having dual role of simultaneous solar power generation and storage. The study of photogalvanics of the Lactic acid reductant-Carmoisine A photosensitizer- Cocamidopropyl betaine (CAPB) surfactant-NaOH alkali has been done under artificial illumination for exploring a most suitable combination of photosensitizer, reductant and surfactant for further enhancing the solar harvesting efficiency. This combination of chemicals (Lactic acid-Carmoisine A-CAPB-NaOH) has shown remarkable improvement in the cell performance. The optimum conditions for cell have also been investigated for optimal cell performance. The electrical output of the cell has been found to depend on the cumulative effect of all cell fabrication variables. The observed power is of the order 1012.70 μW with efficiency 28.84 %. The electrical out-put of the photo-galvanic cells is found almost independent of the size of the illumination window. The initial power generated from the cell was ∼309.0 µW (taken as 100 %), and power at the end of 6th day was ∼0.0009 %. This long term study of the cell in post-illuminated dark conditions shows capacity of the cell to store and release the power over long period of time. Therefore, the Lactic acid reductant-Carmoisine A photosensitizer -CAPB surfactant combination is a good alternative for use in the fabrication of highly efficient photogalvanic cells.

In the present investigation, the formation of nanocrystalline bi-alkali halide (NaCl+KCl) obtained by combined low temperature (cryomilling) with room temperature (RT) milling was reported. The cryomilling, which is endowed with special ability to accelerated fracture and form free ionic salt crystals, is utilized for rapid refinement. This is followed by RT milling to form biphasic nanocrystallites. The bi-phase formation with the time of milling was characterized using a scanning electron microscope (SEM) and transmission electron microscope (TEM). The change in lattice parameter and introduction of micro-strain in the lattice (due to cold work and bi-phase formation) have been characterized using X-ray diffraction and deduce using theoretical calculations. The investigation reveals the influence of milling time on the shape and size of the crystallites along with formation of biphasic NaCl-KCl crystallites with inner core being NaCl surrounded by KCl crystals. The KCl powder particles get deposited on the surface of NaCl crystals to maintain the charge neutrality during ball milling. The shape of NaCl undergoes change from cuboid to cuboctahedron with the progression of milling time due to plastic deformation induced roughing. The temperature-dependent mechanical behaviour and associated mechanism of the milled NaCl-KCl system were discussed and supported by the thermodynamic modal. It is evident, NaCl-KCl is phase separating system, which accentuated at nanosized and hence, the formation of biphasic crystalline structure is observed during combined cryo and RT milling.