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Transient absorption (TA) spectroscopy is one of the most popular experimental methods to measure the excited state lifetimes and charge carrier recombination mechanisms in two dimensional (2D) semiconductors. This fundamental information is essential for designing and optimizing the next generation of ultrathin and lightweight 2D semiconductor-based optoelectronic devices. However, the interpretation of TA spectroscopy data varies across the community. The community lacks a unifying physical explanation for how and why experimental variables such as incident light intensity, sample-substrate interactions, and/or applied bias affect TA spectral data. This Perspective (1) compares the physical chemistry TA literature to nanomaterial physics literature from a historical perspective, (2) reviews multiple physical explanations that the TA community developed to explain spectral features and experimental trends, (3) provides a unifying explanation for how and why trions—and, more generally, Fermi polarons—contribute to TA spectra, and (4) quantifies the extent to which various physical interpretations and data analysis procedures yield different timescales and mechanisms for the same set of experimental results. We highlight the importance of considering trions/Fermi polarons in TA measurements and their implications for advancing our understanding of 2D material properties. [ABSTRACT FROM AUTHOR]

Point Group (PG) symmetries play a fundamental role in many aspects of theoretical chemistry and computational materials science. With the objective to automatize the search of PG symmetry operations of generic atomic clusters, we present a new algorithm called Symmetry Operation FInder (SOFI). SOFI addresses the problem of identifying PG symmetry by framing it as a degenerate shape-matching problem, where the multiple solutions correspond to distinct symmetry operations. The developed algorithm is compared against three other algorithms dedicated to PG identification on a large set of atomic clusters. The results, along with some illustrative use cases, showcase the effectiveness of SOFI. The SOFI algorithm is released as part of the iterative rotations and assignments library, accessible at https://github.com/mammasmias/IterativeRotationsAssignments. [ABSTRACT FROM AUTHOR]

Simulations of photochemical reaction dynamics have been a challenge to the theoretical chemistry community for some time. In an effort to determine the predictive character of current approaches, we predict the results of an upcoming ultrafast diffraction experiment on the photodynamics of cyclobutanone after excitation to the lowest lying Rydberg state (S2). A picosecond of nonadiabatic dynamics is described with ab initio multiple spawning. We use both time dependent density functional theory (TDDFT) and equation-of-motion coupled cluster singles and doubles (EOM-CCSD) theory for the underlying electronic structure theory. We find that the lifetime of the S2 state is more than a picosecond (with both TDDFT and EOM-CCSD). The predicted ultrafast electron diffraction spectrum exhibits numerous structural features, but weak time dependence over the course of the simulations. [ABSTRACT FROM AUTHOR]

Reaction rate theory has been at the center of physical chemistry for well over one hundred years. The evolution of the theory is not only of historical interest. Reliable and accurate computation of reaction rates remains a challenge to this very day, especially in view of the development of quantum chemistry methods, which predict the relevant force fields. It is still not possible to compute the numerically exact rate on the fly when the system has more than at most a few dozen anharmonic degrees of freedom, so one must consider various approximate methods, not only from the practical point of view of constructing numerical algorithms but also on conceptual and formal levels. In this Perspective, I present some of the recent analytical results concerning leading order terms in an ℏ2m series expansion of the exact rate and their implications on various approximate theories. A second aspect has to do with the crossover temperature between tunneling and thermal activation. Using a uniform semiclassical transmission probability rather than the "primitive" semiclassical theory leads to the conclusion that there is no divergence problem associated with a "crossover temperature." If one defines a semiclassical crossover temperature as the point at which the tunneling energy of the instanton equals the barrier height, then it is a factor of two higher than its previous estimate based on the "primitive" semiclassical approximation. In the low temperature tunneling regime, the uniform semiclassical theory as well as the "primitive" semiclassical theory were based on the classical Euclidean action of a periodic orbit on the inverted potential. The uniform semiclassical theory wrongly predicts that the "half-point," which is the energy at which the transmission probability equals 1/2, for any barrier potential, is always the barrier energy. We describe here how augmenting the Euclidean action with constant terms of order ℏ2 can significantly improve the accuracy of the semiclassical theory and correct this deficiency. This also leads to a deep connection with and improvement of vibrational perturbation theory. The uniform semiclassical theory also enables an extension of the quantum version of Kramers' turnover theory to temperatures below the "crossover temperature." The implications of these recent advances on various approximate methods used to date are discussed at length, leading to the conclusion that reaction rate theory will continue to challenge us both on conceptual and practical levels for years to come. [ABSTRACT FROM AUTHOR]

Purpose: To analyze the effectiveness of coating of abutments with antimicrobial agents and their influence on the physicochemical and biologic properties of the coated materials. Materials and Methods: This work was registered in Open Science Framework (osf.io/6tkcp) and followed the PRISMA protocols. A search of two independent reviewers of articles published up to October 29, 2021, was performed in the Embase, PubMed, Science Direct, and Scopus databases. Results: The databases found a total of 1,474 references. After excluding the duplicates, 1,050 remained. After reading the titles and abstracts and applying the inclusion criteria, 13 articles remained and were read in full. A total of 8 articles were included in this systematic review. Different antimicrobial agents have been used to coat abutments, including graphene oxide, polydopamine, titanium and zirconium nitride, lactoferrin, tetracycline, silver, and doxycycline with varied release times. Titanium-coated silver showed a better antimicrobial agent release time of up to 28 days. Chemical analysis confirmed the presence of antimicrobials on the surface after coating. Different pathogenic microorganisms, such as Streptococcus sanguinis, Streptococcus oralis, and Staphylococcus aureus, were inhibited when in contact with the coated surface. Conclusions: This review showed that there is still no consensus on which is the better antimicrobial agent and which coated materials have the better performance. However, the association of surface coating of abutments with antimicrobials is feasible and can benefit many patients, which can support their clinical use to favor the healing process and prevent infections that can lead to treatment failure with dental implants. [ABSTRACT FROM AUTHOR]

Despite the wide existence of vesicles in living cells as well as their important applications like drug delivery, the underlying mechanism of vesicle fusion/fission remains under debate. Classical models cannot fully explain recent observations in experiments and simulations. Here, we develop a constrained self-consistent field theory that allows tracking the shape evolution and free energy as a function of center-of-mass separation distance. Fusion and fission are described in a unified framework. Both the kinetic pathway and the mechanical response can be simultaneously captured. By taking vesicles formed by polyelectrolytes as a model system, we predict discontinuous transitions between the three morphologies: parent vesicle with a single cavity, hemifission/hemifusion, and two separated child vesicles, as a result of breaking topological isomorphism. With the increase in inter-vesicle repulsion, we observe a great reduction in the cleavage energy, indicating that vesicle fission can be achieved without hemifission, in good agreement with simulation results. The force–extension relationship elucidates typical plasticity for separating two vesicles. The super extensibility in the mechanical response of vesicle is in stark contrast to soft particles with other morphologies, such as cylinder and sphere. Our work elucidates the fundamental physical chemistry based on intrinsic topological features of vesicle fusion/fission, which provides insights into various phenomena observed in experiments and simulations. [ABSTRACT FROM AUTHOR]

The on-demand assembly of 2D heterostructures has brought about both novel interfacial physical chemistry and optoelectronic applications; however, existing studies rarely focus on the complementary part—the 2D cavity, which is a new-born area with unprecedented opportunities. In this study, we have investigated the electric field inside a spacer-free 2D cavity consisting of a monolayer semiconductor and a gold film substrate. We have directly captured the built-in electric field crossing a blinking 2D cavity using a Kelvin probe force microscopy–Raman system. The simultaneously recorded morphology (M), electric field (E), and optical spectroscopy (O) mapping profile unambiguously reveals dynamical fluctuations of the interfacial electric field under a constant cavity height. Moreover, we have also prepared non-blinking 2D cavities and analyzed the gap-dependent electric field evolution with a gradual heating procedure, which further enhances the maximum electric field exceeding 109 V/m. Our work has revealed substantial insights into the built-in electric field within a 2D cavity, which will benefit adventures in electric-field-dependent interfacial sciences and future applications of 2D chemical nanoreactors. [ABSTRACT FROM AUTHOR]

The solvent effects on the linear and second-order nonlinear optical properties of an aminonaphtylethenylpyridinium (ANEP) dye are investigated by combining experimental and theoretical chemistry methods. On the one hand, deep near infrared (NIR) hyper-Rayleigh scattering (HRS) measurements (1840–1950 nm) are performed on solutions of di-8-ANEPPS in deuterated chloroform, dimethylformamide, and dimethylsulfoxide to determine their first hyperpolarizablity (βHRS). For the first time, these HRS experiments are carried out in the picosecond regime in the deep NIR with very moderate (≤3 mW) average input power, providing a good signal-to-noise ratio and avoiding solvent thermal effects. Moreover, the frequency dispersion of βHRS is investigated for Disperse Red 1 (DR1), a dye commonly used as HRS external reference. On the other hand, these are compared with computational chemistry results obtained by using a sequential molecular dynamics (MD) then quantum mechanics (QM) approach. The MD method allows accounting for the dynamical nature of the molecular structures. Then, the QM part is based on TDDFT/M06-2X/6-311+G* calculations using solvation models ranging from continuum to discrete ones. Measurements report a decrease of the βHRS of di-8-ANEPPS in more polar solvents and these effects are reproduced by the different solvation models. For di-8-ANEPPS and DR1, comparisons show that the use of a hybrid solvation model, combining the description of the solvent molecules around the probe by point charges with a continuum model, already achieves quasi quantitative agreement with experiment. These results are further improved by using a polarizable embedding that includes the atomic polarizabilities in the solvent description. [ABSTRACT FROM AUTHOR]

The growing concerns over the environmental impact and resource limitations of lithium-ion batteries (LIBs) have driven the exploration of alternative energy storage technologies. Sodium-ion batteries (SIBs) have emerged as a promising candidate due to their reliance on earth-abundant materials, lower cost, and compatibility with existing LIB manufacturing infrastructure. This review explores the recent SIB cathode and anode materials advancements, highlighting the electrochemical properties, structural stability, and potential for large-scale applications. Key cathode materials, such as layered transition metal oxides, polyanionic compounds, and Prussian blue analogs, are analyzed for capacity, stability, and improvement strategies. Challenges in anode development, particularly with hard carbon and alloy-based materials, are also discussed, as well as their performance in electric vehicles and grid storage. Overall, the findings underscore SIBs' potential as a sustainable and cost-effective alternative to LIBs, positioning them as a viable solution to meet the growing energy demands while mitigating environmental impact. [ABSTRACT FROM AUTHOR]

Transition metal chalcogenides (TMCs) are promising electrode materials for supercapacitors because of their improved reversibility, cost-effectiveness, stability, and ability to display diverse oxidation states. Here, we report the synthesis of a composite material, ZnS@CNT, composed of zinc sulfide (ZnS) nanoparticles embedded within carbon nanotubes (CNTs), via one-pot hydrothermal synthesis followed by calcination. The fabricated asymmetric supercapacitor device (ZnS@CNT//AC ASC) delivered a capacitance of 213.9 F g−1, with specific energy and power of 43.3 Wh kg−1 and 6.8 kW kg−1, respectively, by using 2 M KOH as the electrolyte. After 5,000 operational cycles, the device maintained a remarkable capacity retention of 91.79%, highlighting the potential of ZnS@CNT-based ASC devices for future supercapacitor technology. [ABSTRACT FROM AUTHOR]

The applicability of layered transition-metal dichalcogenides (TMDs) for electrode application in lithium-ion batteries (LIBs) necessitates a fundamental understanding of the ion intercalation/de-intercalation mechanisms to identify the factors that affect the cycling stability and/or degradation behavior of the layers. This paper presents the results of an in-situ study of reactions between Li/Li2O and MoS2 inside the transmission electron microscope (TEM) with the basal plane in the edge-on orientation; this orientation makes it possible to examine directly the microstructural and microchemical changes that occur within the van der Waals (vdW) gaps. The experiments enable the characterization of the nanoscale defects that form in real-time as the Li moves into the gaps. Defects are observed to form along the c-planes of MoS2 during in-situ reaction with Li in the TEM. Energy-filtered TEM (EFTEM) analysis shows that these lines are rich in Li and poorer in Mo and S. Atomic-resolution TEM studies in an aberration-corrected TEM show the different stages of the microstructural evolution along these white-line defects. The formation of these defects during intercalation results in the degradation of the layers as cracks are observed to form at the interfaces between the defects and the matrix when external tensile stresses are applied. This cracking subsequently leads to exfoliation and the structural degradation of the intercalated material. These direct observations complemented by atomistic modeling raise several critical questions concerning the ion intercalation and de-intercalation mechanisms that need to be addressed to understand the factors that affect the safety and reliability of layered TMDs in LIBs. This paper is submitted as part of a special issue honoring the contributions of Kamanio Chattopadhyay to Materials Science and celebrating his 75th birthday. Prof. Chattopadhyay's distinguished career included research on metastable materials, which may have much in common with the materials being studied here, and also served for several years as an Editor of the Journal of Materials Science. [ABSTRACT FROM AUTHOR]

Clean and efficient energy has become the foremost objective of human sustainable development. Hydrogen energy, recognized as a green and efficient energy source, has emerged as a focal point worldwide. So far, commonly used hydrogen storage methods pose safety concerns, such as compressing hydrogen into gas cylinders with high-pressure and extremely low-temperature liquefaction. Therefore, the solid hydrogen storage method has received significant attention. 2D materials seek more attention than other solid-state materials due to their astonishing properties, such as wide surface area, layered morphology, magnificent electrical properties, high thermal stability, and tunable interlayer spacing. These outstanding properties make 2D materials a wonderland for hydrogen storage. Many emerging 2D materials have not been explored experimentally but theoretically reveal impactful results for hydrogen storage. To the best of our knowledge, there is no comprehensive review article on 2D materials for hydrogen storage applications. This article presents a comprehensive review of the various 2D materials used for hydrogen storage, such as graphene, MXene, h-BN, borophene, phosphorene, TMDs, aluminene, silicene, etc. The various parameters which influence the hydrogen storage profile of the 2D materials are also discussed. Ultimately, the current significant challenges and future research directions are addressed insightfully to make 2D materials viable for hydrogen storage-based technologies. [ABSTRACT FROM AUTHOR]

Ethers are high value organic compounds widely applied in chemical industry, natural products, material, pharmaceuticals, argochemicals, as well as modern organic synthesis. Herein, we report an adaptive TFA-catalyzed cross-coupling of alcohols with various oxygen nucleophiles (nitro-, halogen-, sulfur-, nitrogen-, aryl-, and alkynyl-substituted aliphatic alcohols), delivering diverse unsymmetrical ethers under mild conditions and simple operation. This protocol features a broad range of substrate scope and high catalytic efficiency (54 examples, up to 99% yield). The decagram scale performance and one-step synthesis of drug molecules evidenced the potential industrial production and practicability of this protocol. [ABSTRACT FROM AUTHOR]

The conversion of diluted CO₂ into high-energy fuels is increasingly central to renewable energy research. This study investigates the efficacy of a Gd₂NiMnO₆ dendritic nanofibrous (DNF) photocatalyst in transforming carbon dioxide to methane through photoreduction. Gd₂NiMnO₆ DNF was found to provide active adsorption sites and control the strand dimensions for metal groups, facilitating the chemical absorption of CO₂. The light-driven photoreduction of CO₂ to CH₄ through biomass valorization has become a sustainable focus area, with photocatalytic CO₂ reduction recognized as a key strategy to mitigate greenhouse gases and achieve carbon neutrality. However, designing active sites with enhanced selectivity and efficiency for CO₂ photoreduction remains challenging. Reducing carbon dioxide is especially crucial in the era of petroleum refineries. This work introduces a reusable, magnetically responsive nanocatalyst for the targeted light reduction of CO₂ to CH₄, utilizing eco-friendly methods, mild thermal conditions, ambient pressure, and sustainable dehydrating agents. This approach provides significant economic benefits and compatibility with functional groups, highlighting the potential of combining 3D nanoparticle structures with sustainable chemistry to create highly efficient catalytic systems for CO₂ to CH₄ conversion. [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO2) is a phase transition material that undergoes semiconductor-to-metal transition at the temperature of about 68 °C. This extraordinary feature triggered intensive research focused on the controlled synthesis of VO2. In this study, we introduce and investigate an original linker- and solvent-free strategy enabling the production of highly porous VO2 nanoparticle-based films. This technique combines a gas-phase synthesis of vanadium nanoparticles and their subsequent atmospheric pressure thermal oxidation. It is shown that the thermochromic behaviour of such produced nanomaterial is at the fixed oxidation temperature strongly dependent on the oxidation time. Concerning this, it was found that there exists an optimal oxidation time (60 s in our study) that assures the production of crystalline VO2 nanoparticles with the highest, reproducible and temporally stable semiconductor-to-metal transition with the resistive switching ratio close to 2 orders of magnitude and dramatic switching of optical properties in the near infra-red spectral region. [ABSTRACT FROM AUTHOR]

Physisorption presents a promising alternative to cryogenic distillation for capturing the most potent greenhouse gas, SF6, but existing adsorbents face challenges in meeting diverse chemical and engineering concerns. Herein, with insights into in-pore chemistry and industrial process design, we report a systematic investigation that constructed two low-cost composites pellets (Al(fum)@2%HPC and Al(fum)@5%Kaolin) coupled with an innovative two-stage Vacuum Temperature Swing Adsorption (VTSA) process for the ultra-efficient recovery of low-concentration SF6 from N2. Record-high selectivities (> 2×104) and SF6 dynamic capacities (~ 2.7 mmol/g) were achieved, while exceptional SF6 productivities (~ 58.7 L/kg), yields (~ 96.8%), and recyclability (~ 1000 cycles) were demonstrated in fixed-bed adsorption-desorption experiments under mild regeneration conditions. 2D solid-state NMR/in-situ FTIR, DFT-D binding/diffusion simulation analyses revealed the multi-site binding mode and the ultra-fast diffusion of SF6 within the channels. The proposed VTSA processes successfully met the dual stringent requirements of both environmental protection and electricity equipment operation: the SF6 recovery of 99.91% accompanied with a SF6 purity/working capacity of 99.91%/2.1 mmol/g, which significantly outperformed the industrial employed adsorbent zeolite 13X and showed only 18.7% the energy consumption of the cryogenic distillation. SF6/N2 separation is crucial for sustainable development. Here, the authors prepared low-cost and robust MOF composite pellets and established a vacuum temperature swing adsorption process with both high recovery and high purity of SF6. [ABSTRACT FROM AUTHOR]

The aim of this study was to treat tannery wastewater by using activated carbon derived from coffee husk to effectively remove total dissolved solids (TDS) and chloride ions. The tannery's wastewater discharged to the environment is often untreated or partially treated. Due to the current worldwide water shortage, it is essential to develop sustainable strategies for managing water resources, such as recycling and reusing after treatment. Therefore, finding cost-effective and eco-friendly methods to purify contaminated water is crucial. In the study, activated coffee husk has been found to be effective for removing TDS and chloride ions from tannery wastewater. Activated coffee husk was evaluated by conducting experiments with chemical activation using phosphoric acid. The carbonized coffee husk was then used to remove total dissolved solids (TDS) and chloride ions from tannery wastewater. To investigate the adsorption process of TDS and chloride ions on the activated coffee husk surface, contact time (1–3 h), pH (5–9), and adsorbent dosage (1–3 g/L) were considered. The activated coffee husk was characterized using SEM (Scanning Electron Microscopy), FTIR (Fourier Transform Infrared Spectroscopy), BET (Brunauer Emmett Teller), and XRD (X-ray diffraction). The adsorption isotherm and kinetics were determined using different models. Design expert was used to optimize TDS and chloride ions adsorption and the optimal conditions were 2.38 h of contact time, pH of 7.19, and 2.54 g/L adsorbent dosage. The removal efficiency of 77.88% for chloride ions and 72.73% for TDS indicates a higher efficacy compared to traditional methods using commercial activated carbon. The Langmuir isothermal model of R2 value for both TDS and chloride ions were 0.9969 and 0.9504 respectively. The adsorption kinetics of TDS and chloride ions follow a pseudo-second-order model, indicating that chemisorption is the rate-limiting step in the process. [ABSTRACT FROM AUTHOR]

Cutting fluid in the material processing process is effective in taking away the heat generated to reduce the cutting temperature, as well as reduce friction and wear to improve the surface performance of the material. It is the most basic and necessary component of the material manufacturing industry. However, mineral oil-based cutting fluids and their additives contain some substances that not only jeopardize human health but also pollute the environment, and a great number of researchers are working hand in hand to find green, environmentally friendly alternatives to traditional mineral oil-based cutting fluids. Among them, vegetable oil is a promising and viable alternative, and some safe nanomaterials have been developed as additives to prepare user-friendly and eco-friendly vegetable oil-based nano-cutting fluids. This paper reviews the formulation, characterization, and mechanism of vegetable oil-based cutting fluids and systematically discusses the application of vegetable oil-based nano-cutting fluids in turning, milling, grinding, and drilling. The results of the review show that high-performance vegetable oil-based nano-cutting fluids could be developed to help advance the realization of green manufacturing. Finally, possible directions for future research on plant-based nano-cutting fluids are proposed. [ABSTRACT FROM AUTHOR]

This paper introduces an organic/inorganic nanoceramic hybrid resin as a replacement for the conventional organic resin coating applied to the silicon steel sheet in electric motors. The organic/inorganic nanoceramic hybrid resin was prepared using the sol–gel method and polymerization. By employing cross-linking and grafting reactions between high thermal conductivity heat dissipation fillers and hybrid resins, excellent insulating coatings with high thermal conductivity and corrosion resistance were achieved. In addition, these coatings exhibit self-adhesive properties, making them suitable as adhesive materials for stacking motor silicon steel sheets. This study performed a film characteristic analysis. The developed coating was then applied to the motor, and its performance was compared with commercially available motors. The experimental results demonstrate that the developed coating enhances the relative protection capability by 88.89%, much higher than the 38.89% of commercially available coatings. The thermal conductivity measurements indicate that the alumina coating increases the thermal conductivity of the silicon steel sheet by 33.14%. In the motor characteristics test, the output power of the aluminum oxide hybrid coating motor increased by approximately 29.6% compared to the traditional welding motor. Additionally, the efficiency of the aluminum oxide hybrid-coated motor increased by 6.7% compared to the control group's welded motor. [ABSTRACT FROM AUTHOR]

Glucose sensing remains a crucial need as diabetes is a worldwide concern. This work reports the application of Nb2CTx—selenium nanoparticle composite material for the nonenzymatic sensing of glucose. The surface morphology of the synthesized composite was analyzed using various microscopic techniques like scanning electron microscopy, transmission electron microscopy, and its structural properties were analyzed using diffraction and spectroscopic methods. A gold disc electrode was modified using the nanocomposite and tested for glucose in an alkaline medium. The sensing was based on the oxidation of glucose on the catalytic surface. The glucose was quantified amperometrically at a significantly lower overpotential of 0.16 V. The sensor showed a good detection range from 2 to 30 mM with a sensitivity of 4.15 µA mM−1 cm−2 and a detection limit of 1.1 mM. [ABSTRACT FROM AUTHOR]

Nickel complexes are a potential candidate for antibacterial and antifungal activity. A new Ni (II) complex, bis(2-methoxy-6-{[(2-methylpropyl)imino]methyl}phenolato)nickel (II) (2), was synthesised by reacting, bis(3-methoxy-salicylaldehyde)nickel (II) (1) with isobutylamine. It was characterised by single crystal X-ray diffraction (ScXRD), UV-Vis, NMR, IR, mass spectrometry, and thermogravimetry (TG) to study its structure and physico-chemical properties. The ScXRD showed a square planar geometry, and monoclinic crystal system with a space group P21/n. The TG analysis revealed its thermal durability pre and post-melting up to 225 oC with a weight loss of only 2%. The optimized molecular structure, energy gap between HOMO and LUMO, and intermolecular interactions were studied by computational methods. The microbial activity evaluation showed significant anti-bacterial activity against E. coli and S. aureus when the concentration exceeded 40 µg/mL, and a prominent anti-fungal activity over C. albicans and C. tropicalis above 30 µg/mL. The values of minimum inhibitory concentration (MIC) for bacteria (MIB) and fungi (MIF) implied its potential to inhibit the growth of microbes. Docking studies revealed that the molecule binds well with proteins such as PDB: 2W9H for Dihydrofolate Reductase of S.aureus as shown by its binding energy of -8.62 kcal.mol− 1. [ABSTRACT FROM AUTHOR]

Limestone mining waste and its derived CaO were checked as an adsorbents of pb2+, Cu2+, and Cd2+ ions from water solution. The characterization of Limestone and calcined limestone was studied by using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), Scanning Electron Microscope (SEM), and Surface area measurements (BET). The optimum conditions of sorbent dosage, pH, initial concentration, and contact time factors were investigated for pristine limestone and calcined limestone absorbents. The results indicate that the optimum initial concentrations of (Ci) were 1200, 500, and 300 ppm for Pb, Cu, and Cd, respectively, using calcined limestone adsorbent, while using the pristine limestone adsorbent, the corresponding optimum initial concentrations were 700, 110, and 50 ppm. In the ternary system sorption, the results indicated that the selectivity sequence of the studied metals by limestone can be expressed as Pb2+ > Cd2+ > Cu2+, while calcined limestone exhibits a higher selectivity for Pb2+ compared to Cu2+ and Cd2+. Hence, various adsorption isotherm and kinetic models were examined to explore different patterns and behaviors of adsorption. So, the results indicate that calcined limestone has great potential for eliminating cationic heavy metal species from industrial water solutions. [ABSTRACT FROM AUTHOR]

In this work, selenium (IV) ions were adsorbed from aqueous solutions by the strongly basic anion exchange resin Amberlite IRA-400. The morphology of the resin before and after Se(IV) sorption was investigated using different techniques such as energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). To determine the ideal sorption conditions, a batch approach was used to examine the variables affecting Se(IV) sorption performance, including pH, shaking time, adsorbent dosage, initial metal ion concentration, and temperature. The results showed the optimal parameters for the highest percentage of selenium (80.25%) at an initial concentration of 100.0 mg L−1, pH 3.0, the adsorbent dosage of 10.0 mg, and the shaking time of 60.0 min. According to the experimental findings, the sorption process was satisfactorily explained by the pseudo-second-order kinetic model. The maximum adsorption capacity at pH 3.0 was 18.52 mg g−1, and the adsorption rather well followed the Langmuir adsorption isotherm. Moreover, exothermic and spontaneous sorption reaction was the result of thermodynamic properties (negativity of both ΔG° and ΔH°). The adsorption phase's random distribution of the resin-solution interface is indicated by the positive value of ΔSo. Finally, the desorption study was performed using different concentrations of desorbing agents; HNO3, HCl, and sodium acetate. The results illustrated that the effective desorbing agent was 1.0 mol L-1 HNO3, with desorption efficiency reaching about 96.4%. Finally, the Amberlite IRA-400 demonstrated excellent adsorption–desorption behavior over five times, suggesting that the Amberlite IRA-400 could be an effective candidate for the sorption of Se(IV) from several metal ions that occur in fission products. [ABSTRACT FROM AUTHOR]

Various photoactive molecules contain motifs built on aza-aromatic heterocycles, although a detailed understanding of the excited state photophysics and photochemistry in such systems is not fully developed. To help address this issue, the non-adiabatic dynamics operating in azanaphthalenes under hexane solvation was studied following 267 nm excitation using ultrafast transient absorption spectroscopy. Specifically, the species quinoline, isoquinoline, quinazoline, quinoxaline, 1,6-naphthyridine, and 1,8-naphthyridine were investigated, providing a systematic variation in the relative positioning of nitrogen heteroatom centres within a bicyclic aromatic structure. Our results indicate considerable differences in excited state lifetimes, and in the propensity for intersystem crossing vs internal conversion across the molecular series. The overall pattern of behaviour can be explained in terms of potential energy barriers and spin-orbit coupling effects, as demonstrated by extensive quantum chemistry calculations undertaken at the SCS-ADC(2) level of theory. The fact that quantum chemistry calculations can achieve such detailed and nuanced agreement with experimental data across a full set of six molecules exhibiting subtle variations in their composition provides an excellent example of the current state-of-the-art and is indicative of future opportunities for rational design of photoactive molecules. Aza-aromatic heterocycles are interesting motifs present in various photoactive molecules, however, their rational design remains challenging due to the lack of details about their excited state photophysics and photochemistry. Here, the authors combine experimental and theoretical studies of UV photoexcitation and associated relaxation dynamics for six azanaphthalenes exhibiting compositional variations, interrogating the difference in excited state lifetimes and the propensity for intersystem crossing vs internal conversion across the molecular series. [ABSTRACT FROM AUTHOR]

A novel gold nanocluster surface molecularly imprinted polyisopropylacrylamide probe (AuNC@MIP) was synthesized for the specific detection of NO2−, using N-isopropylacrylamide (NIPAM) as the functional monomer, gold nanoclusters (AuNC) as the substrate, ethylene glycol dimethacrylate (EGDMA) as the cross-linking agent, and nitrosophenol (NPN) produced from sodium nitrite (NaNO2) and phenol (PN) as the template molecule, N,N-dimethylformamide (DMF) as the solvent, and azobisisobutyronitrile (AIBN) as the initiator. The nanoprobe was characterized using molecular spectroscopy, XPS, TEM, TGA, and zeta potential analysis. The probes revealed a prominent resonance Rayleigh scattering (RRS) peak at 370 nm. Upon addition of NO2−, the RRS intensity at 370 nm decreased due to the RRS energy transfer enhancing. The linear determination range is 0.125–1.50 nmol/L NO2−, with a limit of detection (LOD) of 0.085 nmol/L. The new RRS method was applied to determine NO2− in meat, dairy products, and water samples, with recovery of 96–107% also relative standard deviations (RSDs) of 1.1–8.0%. [ABSTRACT FROM AUTHOR]

Machine learning interatomic potentials (MLIPs) have introduced a new paradigm for atomic simulations. Recent advancements have led to universal MLIPs (uMLIPs) that are pre-trained on diverse datasets, providing opportunities for universal force fields and foundational machine learning models. However, their performance in extrapolating to out-of-distribution complex atomic environments remains unclear. In this study, we highlight a consistent potential energy surface (PES) softening effect in three uMLIPs: M3GNet, CHGNet, and MACE-MP-0, which is characterized by energy and force underprediction in atomic-modeling benchmarks including surfaces, defects, solid-solution energetics, ion migration barriers, phonon vibration modes, and general high-energy states. The PES softening behavior originates primarily from the systematically underpredicted PES curvature, which derives from the biased sampling of near-equilibrium atomic arrangements in uMLIP pre-training datasets. Our findings suggest that a considerable fraction of uMLIP errors are highly systematic, and can therefore be efficiently corrected. We argue for the importance of a comprehensive materials dataset with improved PES sampling for next-generation foundational MLIPs. [ABSTRACT FROM AUTHOR]

The difluoromethyl group is a crucial fluorinated moiety with distinctive biological properties, and the synthesis of chiral CF₂H-containing analogs has been recognized as a powerful strategy in drug design. To date, the most established method for accessing enantioenriched difluoromethyl compounds involves the enantioselective functionalization of nucleophilic and electrophilic CF₂H synthons. However, this approach is limited by lower reactivity and reduced enantioselectivity. Leveraging the unique fluorine effect, we design and synthesize a radical CF₂H synthon by incorporating isoindolinone into alkyl halides for asymmetric radical transformation. Here, we report an efficient strategy for the asymmetric construction of carbon stereocenters featuring a difluoromethyl group via nickel-catalyzed Negishi cross-coupling. This approach demonstrates mild reaction conditions and excellent enantioselectivity. Given that optically pure difluoromethylated amines and isoindolinones are key structural motifs in bioactive compounds, this strategy offers a practical solution for the efficient synthesis of CF₂H-containing chiral drug-like molecules. The difluoromethyl group is a crucial fluorinated moiety, and the synthesis of chiral CF₂H-containing analogs is a powerful strategy in drug design and screening. Here, the authors report a strategy for the asymmetric construction of carbon stereocenters featuring a difluoromethyl group via nickel-catalyzed Negishi cross-coupling. [ABSTRACT FROM AUTHOR]

Amine-assisted two-step CO2 hydrogenation is an efficient route for methanol production. To maximize the overall catalytic performance, both the N-formylation of amine with CO2 (i.e., first step) and the subsequent amide hydrogenation (i.e., second step) are required to be optimized. Herein, a class of Al2O3-supported Ru catalysts, featuring multiple activated Ru species (i.e., metallic and oxidized Ru), are rationally fabricated. Density functional theory calculations suggest that metallic Ru forms are preferred for N-formylation step, whereas oxidized Ru species demonstrate enhanced amide hydrogenation activity. Thus, the optimal catalyst, containing unique Ru clusters with coexisting metallic and oxidized Ru species, efficiently synergize the conversion of CO2 into methanol with exceptional selectivity (>95%) in a one-pot two-step process. This work not only presents an advanced catalyst for CO2-based methanol production but also highlights the strategic design of catalysts with multiple active species for optimizing the catalytic performances of multistep reactions in the future. Amine-assisted two-step CO2 hydrogenation offers an efficient pathway for methanol production. Here, the authors develop Al2O3-supported Ru catalysts that achieve exceptional synergy in converting CO2 to methanol with exceptional selectivity (> 95%) in a one-pot two-step process. [ABSTRACT FROM AUTHOR]

Spray pyrolysis technique was used to deposit Cu2ZnSnS4 (CZTS) thin films onto SLG substrates. The effect of substrate temperature (Tsub), ranging from 300°C to 390°C on their structure and optoelectronic properties. The structural properties reveal that all the prepared CZTS films have a kesterite structure, with a preferential orientation along (112) plane, and presence of secondary phases. XRD data indicated an improvement in crystallinity with an increase in average crystallites size, from 12.29 to 24.73 nm, while Tsub rise up to 390 °C. Raman spectra reveal CZTS formation, with two vibrational modes observed at 335 and 373 cm−1 along with a small Raman peak at 472 cm−1 associated to the Cu2S phase. Transmittance spectra show low values in the visible range with an absorption coefficient of 105 cm−2, The band gap energy (Eg) of the sprayed-CZTS films was consistently found to decrease from 1.6 to 1.38 eV as Tsub is increased from 300 to 390 °C. Hall effect measurements revealed p-type conductivity for all the samples, and the electrical conductivity increased from 1.8 to 150 (Ω.cm)−1 with substrate temperature (Tsub). Overall, experimental results demonstrate that grown CZTS thin films can be considered as a promising absorber material in solar cell devices. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF) compounds are particularly attractive as promising advanced functional materials in energy storage and conversion. However, they exhibit limited electrochemical properties due to their inherent instability and poor electrical conductivity. Herein, a high-conductive electrode material of trimetallic Co/Ni/Fe-MOF was prepared using a solvothermal method. The morphology, specific surface area, and electrochemical properties of the Co/Ni/Fe-MOF were measured. Experimental results show that Co/Ni/Fe-MOF materials have a mesoporous structure and a large available specific surface area of 17.04 m2·g−1. When the discharge current density is 1 A·g−1, the specific capacitance of Co/Ni/Fe-MOF is as high as 2290 F·g−1. An asymmetric supercapacitor device was assembled using Co/Ni/Fe-MOF material as the positive electrode and activated carbon (AC) as the negative electrode. The Co/Ni/Fe-MOF//AC asymmetric supercapacitor has a power density of 7500 W·kg−1 and an energy density of 132.3 Wh·kg−1 in a potential window of 1.5 V. The excellent electrochemical properties of Co/Ni/Fe-MOF make it a wide application prospect as an electrode material for supercapacitors in the energy storage field. [ABSTRACT FROM AUTHOR]

Using a solution technique with a long evaporation process and double-distilled water as the solvent, single crystals of sodium bromide-doped L-alanine (SBLA) were produced during a 55-day growth phase. Advanced techniques were used to evaluate the SBLA crystal, including single XRD, powder XRD analysis, FTIR Spectroscopy, UV–Vis NIR spectroscopy, fluorescence study, TG/DTA study and SHG investigation. Powder XRD and single crystal XRD analysis have been used to identify the sample's structure, space group, volume, Miller indices (hkl) and unit cell properties. This led to the discovery that the structure of the SBLA single crystal was orthorhombic. The lattice parameters of SBLA crystal found by both powder XRD and single crystal XRD methods are almost the same. Utilizing FTIR analysis, the chemical groups included in the developed crystal have been identified. The absorbance and transmittance range, energy band gap value, extinction coefficient, reflectance and refractive index value, optical and electrical conductivity, and skin depth have all been determined by optical research. As a result, a significant absorbance peak in the UV region was found, and 227 nm was found to be the cut-off wavelength and by Tauc's plot, the optical band gap of the sample was found to be 5.447 eV. When analyzing the sample's photoluminescence behavior, sodium bromide-doped L-alanine single crystal (SBLA) exhibits strong green fluorescence emission at 544 nm. The material stability and kinetic and thermodynamic parameters of the SBLA single crystal have been analyzed using TG/DTA study. The SHG efficiency of Sodium bromide-doped L-alanine material is found to be 1.57 higher than that of KDP. The results and discussion of several methods of investigation of the grown SBLA single crystal are detailed in this paper. [ABSTRACT FROM AUTHOR]

For a reliable and risk-free power source, dye-sensitized solar cells (DSSCs) have been the subject of much research. The method is very attractive because of its cheap manufacturing cost, environmentally friendly manufacture, and competitive efficiency. This study constructed a heterojunction as a photoanode for DSSCs using a combination of TiO2 and graphene using a wet chemical technique. According to the XRD and TEM findings, the graphene sheets consist of evenly wrapped spherical nanoparticles with diameters ranging from 30 to 40 nm, and the TiO2 exhibits a tetragonal (anatase) phase. It is common for anatase to have a bandgap energy of 3.15 eV for TiO2, whereas graphene/TiO2 has a bandgap energy of 2.77 eV. With a power conversion efficiency (PCE) of 7.2%, graphene/TiO2 DSSCs outperform cells based on pure TiO2 electrodes by a margin of 2.22%. In particular, graphene's ability to absorb solar light has the potential to improve the power conversion efficiency of DSSCs by increasing the light harvest of dye molecules. In addition, graphene/TiO2 had an average electron transit time of 1.765 ms while TiO2 had an average of 2.981 ms. The research shows that DSSCs' power conversion efficiency may be greatly improved by strategically adding graphene, which can be affordably synthesized, to certain layers of the photoanode. [ABSTRACT FROM AUTHOR]

Copper sulfide (CuS), under the category of metal sulfide, remains as promising anode for Sodium-ion Batteries (SIBs) with a theoretical capacity of 560 mAhg−1. CuS suffers from polysulfide formation, severe capacity fading upon cycling. To address these issues addition of bio-carbon is sought as a measure in this work. A porous carbon has been successively synthesized from sodium alginate source with a specific surface area of 38.78 m2g−1 and an average pore volume of 3.40 nm. The addition of prepared porous carbon to copper sulfide (CuS) enhances stability in the electrochemical performance with the value of 442 mAhg−1 being the initial discharge capacity observed at a current density of 100 mAg−1 over 500 cycles. The technology in performing solid-state reaction is well established and does not demand high infrastructure for atmospheric control thus facilitating large-scale production. Therefore, this work throws light on the benefit of adding bio-carbon to CuS. [ABSTRACT FROM AUTHOR]

Solid solutions of Ga(0.67–0.67x)CoxCr2S4 have been synthesized based on the cation-deficient spinel Ga0.67Cr2S4 with x = 0–0.3. The structural properties of the synthesized compounds were analyzed by X-ray diffraction (XRD), which revealed that they are single-phase in spinel structure type. The surface morphology was examined using scanning electron microscopy (SEM), and it was determined that the average crystalline particle size is within the range of 0.6–1.0 µm. The EDX analysis confirmed that the composition was in compliance with the intended one and that the sample was homogeneous. A study of the structural properties revealed that the cationic vacancies and gallium ions in the spinel structure are ordered, resulting in the formation of a superstructure within the tetrahedral sublattice. Consequently, the solid solutions under investigation are classified within the F 4 ¯ 3 m space group, rather than Fd 3 ¯ m . This study demonstrates how the magnetic properties of the investigated solid solutions are influenced by the presence of ordered vacancies. A change from paramagnetic to antiferromagnetic with weak ferromagnetism was observed for all compositions. The magnetic transition temperatures (TN = 19–34 K for x = 0–0.3, respectively) have been determined. It has been demonstrated that the substitution of gallium by cobalt leads to an increase in the magnetic transition temperature. Furthermore, an increase in coercivity (HC, from 1.41 to 2.62 kOe) and residual magnetization (MR, from 0.007 to 0.034 μB) was observed in series with increasing cobalt concentration. [ABSTRACT FROM AUTHOR]

Garnet-type Li7La3Zr2O12 (LLZO) solid electrolytes for solid-state lithium batteries have garnered significant research interest due to their excellent lithium-ion conductivity and wide electrochemical stable window. However, the LLZO-based electrolytes still face challenges in practical applications, such as instability in solid–solid contact, surface defects, and the presence of contaminants, which lead to interface failure between the electrolyte and the electrodes. This review article presents a comprehensive overview of the LLZO-based solid electrolytes, focusing on its materials properties and interface issues. The review begins with an introduction to the crystal structure of LLZO and its Li-ion conductivity and delves into the interface between LLZO and lithium anodes, discussing physical, chemical, and electrochemical stability, as well as strategies for interface regulation. The interface between LLZO and the cathode is also examined, including interface stability and engineering. Finally, the review summarizes the current understanding of LLZO and provides an outlook for future research directions. [ABSTRACT FROM AUTHOR]

In response to the energy crisis, researchers are working on creating novel materials for the electrodes of energy storage devices, particularly supercapacitors. Furthermore, in order to promote an environmentally friendly environment, the contamination of industrial effluent with various colors is becoming a significant problem that needs to be addressed right now. Ce-Mo co-doped NiO nanomaterials have been created for the first time to address this problem. The capacitive and photocatalytic performance of NiO was greatly influenced by the morphology, which was significantly altered by the co-doping of Ce and Mo. The characterization techniques like XRD, SEM, TEM, EDX, BET and XPS were used to investigate the specific physical properties of the as-prepared nanomaterials. CV, GCD, and EIS experiments were used to evaluate the electrochemical characteristics. CV analysis has revealed that among the various Ce and Mo co-doped NiO samples, Ce0.05Mo0.05NiO based on nanowires has offered the highest specific capacitance, i.e., 1108.68 F/g. The EIS studies have revealed that Ce0.05Mo0.05NiO nanowires are highly conductive in nature. Moreover, after 10,000 CV cycles, 85.7% capacitance retention was noted for Ce0.05Mo0.05NiO nanowires. The photocatalytic performance of as-prepared nanowires was assessed against the model dye methyl red (MR). During the optical study of as-prepared co-doped NiO nanomaterials, the Ce0.05Mo0.05NiO sample has shown a reduced optical band gap of 2.95 eV, which is very helpful for the photocatalytic conduct. The optimized Ce0.05Mo0.05NiO nanowires have exhibited 97% photodegradation activity against the methyl red (MR) and strong catalytic stability (88.7%). On the basis of such astonishing performance, it is suggested that the as-reported Ce and Mo co-doped NiO material based on nanowires is a potential candidate for the application in energy storage and water purification applications. [ABSTRACT FROM AUTHOR]

In this paper, an electrospinning composite material for solar energy storage was prepared by combining 2-methyl-acrylic acid 6-[4-(4-methoxy-phenylazo)-phenoxy]-hexyl ester (MAHE) as molecular solar thermal (MOST) molecule and polyethylene glycol-2000 (PEG) as phase change material (PCM) using electrospinning technique for the first time. In the composite fibers, both kinds of energy storage molecules successfully carried out energy storage and release behavior, and the enthalpy value reached 11.623 J/g. MAHE molecule in the composite showed good fatigue resistance in the reversible charge and discharge process within 50 cycles. It is more noteworthy that the materials obtained by electrospinning have excellent leakage resistance. The experimental results show that electrospinning has a wide development potential in the preparation of solar energy storage materials. [ABSTRACT FROM AUTHOR]

This study explores the electrochemical, thermal, and structural properties of alum as a potential material for energy storage devices, particularly capacitors and pseudocapacitors. Alum, a cost-effective and abundant material, was characterized using several advanced techniques, including thermogravimetric analysis, dynamic light scattering, and zeta-potential measurements, which provided valuable insights into its thermal stability, particle size distribution, and surface charge. Surface area analysis through the BET method revealed a specific surface area of 12.6 m2/g, highlighting the material's porous nature. Electrochemical investigations through cyclic voltammetry demonstrated capacitive behavior with potential pseudocapacitive contributions, evidenced by observable redox peaks at scan rates ranging from 20 to 120 mV/s. The highest specific capacitance recorded was 9.48 F/g at a scan rate of 20 mV/s. Galvanostatic charge–discharge measurements confirmed charge–discharge characteristics aligned with capacitor behavior, showing a decrease in specific capacitance with increasing current density. This work underscores the potential of alum as a promising low-cost alternative for supercapacitor applications, particularly for low-power energy storage devices. With further optimization of its electrochemical performance and long-term cycling stability, alum could offer a sustainable solution for the development of efficient energy storage technologies. This study contributes to the growing international interest in sustainable materials for energy storage, addressing a significant gap in research and offering new avenues for future exploration in supercapacitor and pseudocapacitor technologies. The work aligns with global efforts to innovate cost-effective and environmentally friendly energy solutions, highlighting alum's role in advancing the field of energy storage by providing a novel, yet accessible material with high potential for widespread application. [ABSTRACT FROM AUTHOR]

Bis (8-hydroxyquinoline) copper (CuQ2) is an important organometallic complex based on a central metal cation coordinated to quinolate ligands. However, CuQ2 exhibits limitations such as low fluorescence intensity, short fluorescence lifetime, and low efficiency of visible light absorption. In this study, density functional theory (DFT) calculations were performed to investigate the frontier molecular orbitals of CuQ2, revealing its potential for excellent luminescence properties. Subsequently, CuQ2 was synthesized using physical vapor deposition (PVD), yielding micron-sized CuQ2 particles. CuQ2 micron particles were characterized using scanning electron microscopy (SEM), X-ray diffraction spectroscopy (XRD), fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), ultraviolet visible spectroscopy (UV–Vis), photoluminescence and fluorescence lifetime. The results demonstrate that the deposition temperature significantly influences the morphology, thermal stability and fluorescence properties of CuQ2. At a deposition temperature of 200 °C, the CuQ2-C sample forms spherical micron particles with uniform morphology, enhanced thermal stability, optimal visible light absorption efficiency, and highest fluorescence intensity. The CuQ2-C sample exhibits a maximum emission wavelength of 660 nm, a maximum excitation wavelength of 333 nm, and a fluorescence lifetime of 10.646 μs. [ABSTRACT FROM AUTHOR]

Water repellency of superhydrophobic protective film is of great interest to anti-corrosion of metallic materials due to its reduced contact area with water containing aggressive ions and self-cleaning effect. In this study, a facile electrochemical method was presented for preparing superhydrophobic film with excellent anti-corrosion and self-cleaning properties on Al alloy. The superhydrophobic film comprised nickel–cobalt phosphate (NiCoPO) with a hierarchical micro-nano structure and stearic acid (STA) with low surface energy, while the NiCoPO provides an appropriate roughness and STA offers an inert chemical state. As expected, the superhydrophobic film of NiCoPO/STA on Al alloy demonstrates a champion water contact angle of 163º and corrosion protection efficiency of 97.38%. Moreover, the water flow impact-bounce and abrasion measurements on the NiCoPO/STA surface demonstrate that the superhydrophobic film possesses decent mechanical durability. This facile electrochemical deposition method paves a universal pathway to fabricate superhydrophobic protective film with remarkable anti-corrosion and self-cleaning performance on metallic substrates. [ABSTRACT FROM AUTHOR]

In recent years, the catalytic oxidation of cheap and easily available alcohols to value-added carboxylic acids has attracted considerable interest. In this work, a post-synthetic modification strategy was employed to anchor Cu species to coordinate with the -NH2 in UiO-66-NH2(Ce), obtaining the catalyst Cu-UiO-66-NH2(Ce). The catalyst exhibited excellent performance for the direct oxidation of alcohols to carboxylic acids under mild reaction conditions without extra bases. The synthesized materials were characterized by XRD, SEM, XPS, BET, FT-IR, Raman and ICP-OES, the results show that Cu species were successfully anchored onto UiO-66-NH2(Ce) by the coordination with N atoms. Moreover, the coordination between Cu ions and N atoms as well as the unique structure of UiO-66-NH2(Ce) could provide uniformly catalytic active centers on heterogeneous catalyst, which are essential for the high catalytic performance of the catalyst. Furthermore, the recyclability of the catalyst was also investigated, which can be recovered and recycled for 10 times without significant loss of catalytic activity. This work provides an efficient and cost-effective approach to the direct oxidation of alcohols to carboxylic acids. [ABSTRACT FROM AUTHOR]

The depletion of fossil fuels and growing environmental concerns necessitate the exploration of renewable energy sources. Biodiesel, a promising alternative fuel derived from sustainable feedstock, has attracted considerable attention. This study investigates the catalytic esterification of oleic acid, a readily available fatty acid, with ethanol for biodiesel production using a novel heterogeneous catalyst, ZrO2/Al2O3. Crystalline ZrO2/Al2O3 was successfully synthesized and characterized using X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) surface area analysis, and Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and temperature programmed desorption NH3-TPD to understand its structural and textural properties. The characterized ZrO2/Al2O3 was then employed to catalyze the esterification reaction. The influence of reaction parameters, including temperature, alcohol-to-oleic acid molar ratio, and catalyst loading, was systematically evaluated. Under optimal conditions (70 °C, 10:1 alcohol-to-oleic acid molar ratio, and 4 wt% catalyst loading), a remarkable 90.5% conversion of oleic acid to biodiesel was achieved. Furthermore, the catalyst exhibited reusability, demonstrating its potential for sustainable biodiesel production from low-grade oleic acid feedstock. [ABSTRACT FROM AUTHOR]

To observe the chemical mechanical polishing (CMP) process at the atomic scale, reactive force field molecular dynamics (ReaxFF-MD) was employed to simulate the polishing of 6 H-SiC under three conditions: dry, pure water, and H2O2 solution. This study examined the reactants on the surface of 6 H-SiC during the reaction in the H2O2 solution, along with the dissociation and adsorption processes of H2O2 and water molecules. The mechanisms for atom removal during the CMP process were elucidated. Variations in the number of different bonds over time and changes in the number of amorphous SiC atoms across various environments were analyzed. A comparison was made regarding the surface morphology of SiC after polishing with diamond abrasives in the three distinct environments.The results indicate that H2O2 and water molecules can dissociate into -OH, -H, and -O-. Si atoms form Si-C bonds with carbon atoms in the abrasive or connect with carbon atoms via -O- bridges to form Si-O-C for removal. C atoms are primarily removed in the form of carbon chains. Abrasive grinding can promote the dissociation of -H2O and -OH. Both water and H2O2 solutions can mitigate surface structural damage during the polishing process, with the H2O2 solution showing superior effectiveness. [ABSTRACT FROM AUTHOR]

The utilization of single crystals is exponentially growing in optoelectronic devices due to their exceptional benefits, including high phase purity and the absence of grain boundaries. However, achieving single crystals with a porous structure poses significant challenges. In this study, we present a method for fabricating porous single crystals (porous-SC) of Cs2AgBiBr6 and related halide double perovskites using an infrared-assisted spin coating technique. The porous-SC are formed through a non-classical crystallization process, where oriented crystallographic platelets assemble into porous-SC clusters and merge to create iso-oriented single crystalline building blocks, with pore regions primarily located in the gaps between the platelets. Large porous square-shaped Cs2AgBiBr6 halide double perovskite (HDP) single crystals with lateral dimension ~ 10 to 50 μm and few µm thickness are realized with preferred orientation along {h00} on the FTO substrate upon subsequent spin-coating of layers. Analysis using angle-resolved polarized Raman spectroscopy, X-ray diffraction and transmission electron microscopy confirms the formation of single crystals of Cs2AgBiBr6. Further, to get a uniform coating of highly interconnected porous-SC clusters, wiping method under IR illumination is employed. Solar cell devices fabricated from these porous-SCs perform better with JSC =1.40 mA/cm2, VOC=1.04 V and η = 0.86% than the conventional polycrystalline thin films with JSC = 0.55 mA/cm2, VOC=0.94 V and η = 0.28%. Cs2AgBiBr6 porous-SC shows potential for a wide range of optoelectronic and photoelectrochemical applications. [ABSTRACT FROM AUTHOR]

We have developed a novel S-scheme mechanism to expand the photoresponse range of Bi2SiO5. This study reports the successful creation of a CN/BS heterojunction photocatalyst, which is composed of g-C3N5 and Bi2SiO5. The synthesis was achieved through a simple two-step procedure, involving hydrothermal treatment and subsequent calcination. The 10% CN/BS exhibits superior photocatalytic efficiency. When exposed to visible light, the CN/BS heterojunction photocatalyst achieves a removal rate of 98.8% regarding the breakdown of Rhodamine B (RhB), outperforming Bi2SiO5 by a factor of 5 and g-C3N5 by a factor of 3. Furthermore, the removal rate for Ciprofloxacin (CIP) reaches 96.0%, which is double that of Bi2SiO5 and 14 times higher than that of g-C3N5. It is evident that the photodegradation efficiency of 10% CN/BS towards organic pollutants significantly surpasses that of the precursor composite materials. The improved photocatalytic performance is likely due to the larger specific surface area, more efficient light harvesting, and the construction of an heterojunction. Crucially, the proposition of an S-scheme hypothesis for charge transport within the CN/BS heterojunction photocatalyst marks a pivotal advancement. This concept is of substantial importance for both the theoretical exploration and the practical deployment of photocatalytic materials. [ABSTRACT FROM AUTHOR]

Despite recent advancements in organic photovoltaics (OPVs), further improvements in power conversion efficiency (PCE) and device lifetime are necessary for commercial viability. Strategies such as optimizing the molecular orientation and minimizing the charge traps of organic films are particularly effective in enhancing photovoltaic performance. In this study, we successfully utilized vacuum electrospray deposition (VESD) to achieve favourable face-on stacking geometries while preserving the integrity of the interfaces in poly(3-hexylthiophene-2,5-diyl) (P3HT): [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) bulk heterojunction (BHJ) films. Unlike conventional spin-coated (SC) P3HT: PCBM BHJ films, which predominantly exhibit an edge-on orientation, VESD facilitates a beneficial face-on orientation, improving vertical charge transport through enhanced π-π stacking interactions. Furthermore, VESD effectively eliminates residual solvents during film formation, ensuring well-defined interfaces between the layers in the OPV devices. As a result, the VESD OPVs demonstrated enhanced PCE and extended operational lifetimes compared to their SC counterparts. Impedance spectroscopy analysis confirmed that the VESD OPVs possessed significantly higher electron mobility and longer electron lifetimes, indicating reduced charge traps and improved charge dynamics. These results highlight the potential of VESD as a versatile technique for controlling molecular orientation in solution-processable organic semiconductors, enabling the development of highly efficient devices with fewer charge traps without relying on synthetic or epitaxial methods. [ABSTRACT FROM AUTHOR]

A microbial fuel cell (MFC) is a modern, environmentally friendly, and cost-effective energy conversion technology that utilizes renewable organic waste as fuel, converting stored chemical energy into usable bioelectricity in the presence of a biocatalyst. Despite advancements in MFC technology, several challenges remain in optimizing power production efficiency, particularly regarding anode materials and modifications. In this study, low-cost biosynthesized iron oxide nanoparticles (Fe3O4 NPs) were coated with a polyaniline (PANI) conducting matrix to synthesize hybrid Fe3O4/PANI binary nanocomposites (NCs) as modified MFC anodes via an in-situ polymerization process. Characterization techniques, including UV–Vis, XRD, SEM, and FT-IR, revealed the successful synthesis of green-routed nano-scaled materials with altered optical properties after matrix coating, high crystallinity in the iron oxide phase, rougher surface morphology, and characteristic Fe–O peaks at 594 cm⁻1. Additionally, the electrochemical behavior of the prepared nano-materials was characterized by cyclic voltammetry (CV), where low ΔEp values (0.473 V) for Fe3O4/PANI NCs indicated the presence of reversible charge transfer mechanisms at the electrode surface, reflecting a high rate of electron transfer. The synthesized nanocomposite was used to modify pencil graphite anodes to construct four single-chamber MFCs: bare pencil graphite anodes, pencil graphite anodes modified with Fe3O4, PANI, and Fe3O4/PANI nanocomposites. The maximum open circuit voltage (OCV) value was 645 ± 24.50 mV, with a high power output of 424.51 ± 6.86 mW/m2 and current density of 2475.01 ± 1.23 mA m−2 produced by the Fe3O4/PANI NCs modified pencil graphite electrode, which is more than six times the efficiency in terms of power density compared to the unmodified pencil graphite electrode (PGE). These results demonstrate that the synthesized nanocomposite plays an effective and value-added role in modifying traditional carbon anode electrodes within an MFC energy conversion device system. [ABSTRACT FROM AUTHOR]

Further improvements to lithium-ion and emerging battery technologies can be enabled by an improved understanding of the chemistry and working mechanisms of interphases that form at electrochemically active battery interfaces. However, it is difficult to collect and interpret spectra of interphases for several reasons, including the presence of a variety of compounds. To address this challenge, we herein present a vibrational spectroscopy and X-ray diffraction data library of ten compounds that have been identified as interphase constituents in lithium-ion or emerging battery chemistries. The data library includes attenuated total reflectance Fourier transform infrared spectroscopy, Raman spectroscopy, and X-ray diffraction data, collected in inert atmospheres provided by custom sample chambers. The data library presented in this work (and online repository) simplifies access to reference data that is otherwise either diffusely spread throughout the literature or non-existent, and provides energy storage researchers streamlined access to vital interphase-relevant data that can accelerate battery research efforts. [ABSTRACT FROM AUTHOR]