Five new organic sensitizers of type Donor-π-Acceptor (D-π-A) were designed and synthesized to investigate the effect of anchoring mode and conjugation length towards TiO2 film which leads to influence the efficiency of the fabricated dye sensitized solar cells. These dyes were synthesized based on the triphenylamine as electron donor, a series aromatic amine as π-conjugated spacers and anchoring/acceptor groups. The optical absorption of sensitizers shows red shift as well as high molar extinction co-efficient with extension of the π-conjugation. The DSSC based on AD series show power conversion efficiency (PCE = η) ranging from 1.53 – 6.89 % under simulated AM 1.5 G. DSSCs based on AD4 and AD5 produce maximum IPCE of 74.8% and 71.9%, respectively while those based on AD1 and AD5 in particular produce maximum IPCE below 50%. This variation is due to an increase in conjugation and the number of anchoring groups. The short circuit current (Jsc), open circuit voltage (Voc), field factor (FF), and quantum efficiency (ƞ) also increased with increase in IPCE values. High Jsc values signified high electron collecting efficiencies, which in turn denote faster electron diffusion rates. Additionally, a rise in the value of the Voc might raise the life time of the DSSC. The PCE (ƞ) values of AD dyes especially those of AD4 and AD5 (ƞ = 6.86% and 6.89% respectively) were seen to be higher than those of some triphenylamine based DSSCs (SD series with elongated thiophen units) whose PCE values ranged from 1.91% to 3.92%.

Medicinal plants are one of the sources of biologically active compounds that determine their therapeutic effect. Water infusions and decoctions, as well as tinctures and extracts, are currently used in phytotherapy. Sonication treatment is an effective approach to increasing the efficiency of active component extraction from plant material. Application of sonication reduces the time and consumption of extractant, as well as uses mild conditions. Sonication-assisted water extraction was applied to the various medicinal plants traditionally used in phytotherapy. Water extracts from herbs, leaves, bark, infructescences, flowers, roots, and rhizomes were studied using total antioxidant parameters obtained by constant-current coulometry. Eleven samples of commercially available medicinal plants were investigated (bark of Quercus robur and Frangula alnus, infructescences of Alnus incana, rhizomes of Potentilla erecta and Bergenia crassifolia, roots and rhizomes of Sanguisorba officinalis, herb of Leonurus, flowers of Tilia×europaea and Matricaria chamomilla, leaves of Salvia officinalis and Urtica dioica). Total antioxidant capacity (TAC) and ferric reducing power (FRP) based on the reactions with electrogenerated bromine and ferrocyanide ions, respectively, were evaluated. The effect of sonication time in the range of 10–30 min was tested. The highest yield of antioxidants was achieved using a 30 min treatment. The TAC and FRP values were varied depending on the part and type of medicinal plant. The highest TAC and FRP were obtained for the extracts obtained from roots and rhisomes. The FRP values indicate the impact of phenolic compounds, which is significant for the samples under study. Total antioxidant parameters of infusions, decoctions, and sonication-assisted extracts were compared.

Bioadditives are often used around the world as a part of the daily human diet. Contrary to pharmaceuticals, bioadditives are not subject to rigorous quality control, and their full chemical composition is usually unknown. Therefore, the determination of active components in bioadditives is of high importance and can be achieved using voltammetry. Novel voltammetric sensors were developed for the quantification of L-tyrosine and diosmin in bioadditives. A glassy carbon electrode (GCE) modified with SnO₂ nanoparticles dispersed in sodium dodecyl sulfate and electropolymerized Eriochrome Black T allowed for the determination of L-tyrosine. The effect of its surfactant nature was tested. A GCE covered layer-by-layer with carboxylated multi-walled carbon nanotubes and polydopamine responded to diosmin. The conditions of electropolymerization were optimized using a target analyte voltammetric response. The electrodes' surface morphology and electron transfer properties were estimated by means of scanning electron microscopy and electrochemical methods. The increases in the electroactive surface area and electron transfer rate were confirmed. The electrooxidation parameters of L-tyrosine and diosmin were found. The electrodes were used as voltammetric sensors in Britton–Robinson buffer with a pH of 2.0 in differential pulse mode. The linear dynamic ranges of 0.75–100 μM for L-tyrosine and 0.75–25 and 25–100 μM for diosmin were achieved, with detection limits of 0.66 and 0.25 μM, respectively. The selectivity of the sensors’ response to target analytes in the presence of typical co-existing compounds was proven. The practical applicability of the developed sensors was shown on real samples. A comparison to standard high-performance liquid chromatography confirmed similar levels of precision of the methods.

The hydrogen evolution reaction (HER) has been widely studied due to the increasing demand for hydrogen as fuel. However, the lack of efficient storage methods restricts the broad adoption of hydrogen-powered devices. Understanding transition metals' hydrogen adsorption capacity is essential for the better design of these devices because they are frequently used as catalysts for many kinds of hydrogen evolution reactions.

The first-principle DFT calculation was carried out using the VASP package to obtain the optimized geometries of hydrogen adsorption on metal surfaces. Two sets of surfaces—a) coinage metals (Ag, Au, and Cu) and b) non-coinage metals (Pt, Pd, Ni, and Co)—are considered. On each metal surface, the hydrogen adsorption energies are obtained at varying surface coverage ratios until the hydrogen evolution is kinetically and thermodynamically spontaneous.

The hydrogen adsorption energies decreased on all metal surfaces with increased hydrogen atoms on the surface. Later, the Tafel hydrogen evolution mechanism is used to define the spontaneous hydrogen evolution from the surfaces. The hydrogen evolution is quicker on the Au surface, and non-coinage metals, namely Ni, Co and Pd, have slower hydrogen evolution. Due to the strong adsorption of hydrogen atoms on metal surfaces, hydrogen atoms are found on the surface even after the HER, which experimental studies have also validated.

Perovskite halides with a typical composition of CH₃NH₃PbI₃ provide high photoconversion efficiencies and lightweight/flexible solar cells. Since the main element lead (Pb) is toxic, perovskites without Pb (Pb-free) should be developed from the viewpoint of natural environments and human health. In addition, methyl ammonium (CH₃NH₃, MA) is an unstable molecule in the crystal, and MA-free perovskites are also mandatory to improve their structural stabilities. The aim of the present study is to clarify the electronic structures and properties of copper (Cu), germanium (Ge), or tin (Sn)-based MA/Pb-free perovskite halides using first principles calculations. Monovalent copper (Cu⁺), rubidium (Rb), and cesium (Cs) were introduced at the MA sites, and various transition elements and typical elements such as Ni, Cr, Fe, Zn, and others were also induced at the Pb site. Pb-free double perovskite bromides were also found to be the suitable photovoltaic materials, which would be due to high electron density of Ge compared with Sn. The double perovskites have wide energy gaps and stabilities compared with the ordinary perovskites, and the hybridization of Ge/Sn would influence the electronic structures. Total energies of Cs-based perovskites were reduced by the Cu⁺ addition. The band gap energies of Cu-based Pb-free chlorides with transition metals provided suitable values for solar cells. Carrier mobilities and crystal structures of the perovskites could be stabilized by the overlapping of electron orbitals between the chloride octahedron and Cu⁺. The Cu⁺ at the MA-site would be effective to control the structures and stabilities of the all-inorganic perovskites, which would expand the multiplicity of the perovskites; as a result, the α-formamidinium cesium lead triiodide was stably formed by the addition of Cu⁺.

Good plant growth and high productivity largely depend on mineral fertilizers. Therefore, identifying new raw materials for the production of these fertilizers is crucial. The analysis of newly discovered minerals is essential to uncover their potential uses. In this study, Energy-Dispersive X-ray Spectroscopy (EDS) combined with Scanning Electron Microscopy (SEM) was used to examine the elemental composition and surface morphology of a mineral sample. The sample was taken from the "Doutosh" mine, located on the southern border of Uzbekistan, at a depth of 30-35 meters. The topsoil layer was removed using specialized methods, allowing access to the ore for further analysis. The SEM-EDS analysis revealed that the main constituents of the mineral were oxygen (32.95%), manganese (27.77%), and chromium (9.97%), along with smaller amounts of carbon, silicon, calcium, iron, and other trace elements. The multi-elemental composition of the mineral was confirmed, with manganese and chromium being the primary contributors. These findings suggest that the mineral holds potential for industrial applications, particularly in the fields of materials science and metallurgy. Moreover, by studying the functional characteristics of the mineral and assessing its environmental impact, plans are being made to develop manganese-based fertilizers for plant growth using this mineral resource. This could serve as a new branch of the chemical industry in Uzbekistan.

The spread of infectious diseases is a consequence of environmental contamination due to the presence of pathogenic agents in aqueous media. Therefore, it is of a vital importance the development of an economical and eco-friendly method to eradicate these microorganisms. The use of photodynamic inactivation (PDI) with photosensitizers conjugated to magnetic nanoparticles (MNPs) has emerged as a successful approach for the rapid elimination of microorganisms. For this purpose, MNPs of Fe₃O ₄ coated with silica and terminal amine groups were synthetized. After that, 5,10,15,20tetrakis(pentafluorophenyl)porphyrin (TPPF₂₀) was covalently immobilized on the MNPs by nucleophilic aromatic substitution reaction. Then, the remaining pentafluorophenyl groups of attached to MNPs were substituted by polyethylenimine (PEI) or spermine (SP). Absorption and fluorescence emission spectra of these conjugates showed the typical bands of tetrapyrrolic macrocycles in water. On the other hand, photodynamic activity investigations indicated that these MNPs generated singlet molecular oxygen and superoxide anion radical in solution. In addition, PDI studies were carried out with Staphylococcus aureus and Escherichia coli. These MNPs were able to eradicate microorganisms (>6 log decrease) after 30 min of irradiation with white light. Therefore, the basic amine groups can be used to generate positive charges at physiological pH, which improve the interaction with the bacteria. Furthermore, this procedure facilitates the recycling and reuse of these MNPs after treatments using a magnetic field. These
results indicate that conjugates of TPPF₂₀ to MNPs are interesting photodynamic materials to eliminate pathogens.

Conductive polymers (CPs) are a type of organic materials that combine the flexibility and processability of polymers with the electrical properties of inorganic semiconductors, making them highly suitable for sensor development. These materials, including polyaniline, polypyrrole, polythiophene, and PEDOT, exhibit unique electrical, optical, and chemical properties, enabling their use in the design of highly sensitive and selective sensors for a broad range of environmental, industrial, and biomedical applications. The conductivity of CPs is derived from their conjugated structure, which can be “tuned” through doping and functionalization to optimize the performance of various sensing materials. This systematic review provides a comprehensive examination of the synthesis techniques, conductive mechanisms, and structural modifications that make CPs effective in chemical, gas, and biosensors. It discusses how CPs, which have significant advantages in terms of selectivity and responsiveness, enable real-time, high-precision detection of chemical and biological analytes. The paper also categorizes the types of sensors made with CPs, including chemical sensors for pollutant detection, gas sensors for CO₂, CO, and NH₃ sensing, and biosensors for medical diagnostics like glucose monitoring. In addition, this systematic review addresses important issues such as enhancing sensor sensitivity, selectivity, and stability over time, all of which are significant in providing dependable performance in practical applications. This systematic review highlights the significance of conductive polymers in developing sensor technologies and promoting innovation in fields ranging from environmental monitoring to biomedical diagnostics by addressing current advancements and identifying future research directions.

Swarming motility (SM) is a term that describes the rapid movement of bacteria across a surface with the assistance of their flagellar rotation. Flagellar motility has been discovered to drive transitory cell–surface interactions and overpower the electrostatic repulsive forces at these interfaces. As a result, it is necessary for bacterial self-aggregation and irreversible surface adherence, both of which are necessary for the creation of antibiotic resistance in bacteria. In bacteria such as Pseudomonas aeruginosa, Escherichia coli, and Proteus mirabilis, SM is a crucial pathogenicity factor that allows them to acquire resistance to several antibiotics. As the prevalence of antibiotic resistance has increased, researchers have begun to investigate alternate approaches to inhibiting the motility of bacteria. One such approach is the utilization of nanoparticles (NPs). Within the objectives of this work, the size-dependent impacts of nanoparticles such as copper oxide (CuO), zinc oxide (ZnO), gold nanoparticles (AuNPs) and chitosan nanoparticles (CS-NPs) on the prevention of bacterial swarming are investigated. These findings highlight the significance of nanoparticle size and concentration in the process of modifying motility in bacterial swarming. The results of this statistical analysis demonstrate that the effectiveness of nanoparticles in preventing antibiotic resistance by suppressing SM is contingent on the size of the nanoparticles and the concentration that is employed. The information that we required for the data analysis was acquired from several different research articles in this instance. Our study method included a descriptive analysis and cross-sectional study of these data. Through our inquiry, we illustrate how NPs' anti-swarming activity is affected by their size and concentration.

Biofilm formation is a bacterial phenotype by which bacteria can make antibiotic resistance. The extracellular polymeric substances (EPS) matrix of biofilm protects bacteria against environmental stresses, including antibiotics, immunological reactions, and disinfectants. The inhibition of antibiotic resistance is now a concern in medical science. In nanotechnology area nanoparticles are showing promising effect in inhibiting biofilm formation. Pseudomonas aeruginosa, Streptococcus pneumoniae, Listeria monocytogenes, and Escherichia coli are some of the bacteria that are susceptible to the powerful antibacterial and antibiofilm activities that are exhibited by several nanoparticles. These nanoparticles can generate reactive oxygen species (ROS) and release ions, which make them effective for inhibiting biofilm formation. Some nanoparticles bind with bacterial membrane or bacterial protein to remove antibiotic resistance and to make them possible in antibiofilm activities. The effect of nanoparticles in antibiofilm activity may depend on size. Because generating reactive oxygen species (ROS) and releasing ions property is dependent on size. This statistical study will show the utilization of nanoparticles in inhibiting antibiotic resistance by inhibiting quorum sensing and by inhibiting biofilm formation will depend on their size. We will demonstrate the effect that the sizes of the NPs have on the antibiofilm activity through our investigation. In this instance, we obtained information needed for data analysis from a variety of research articles. The descriptive analysis and cross-sectional study are all components of our analysis, which involves employing those data. The results of this investigation will indicate that size influences the antibiofilm activity.