Soil contamination by heavy metals represents a critical environmental risk. Innovative and sustainable remediation strategies are urgently needed to address this global challenge. Biochar, derived from biomass pyrolysis, has gained attention as an eco-friendly material for heavy metal adsorption. However, its adsorption performance is highly dependent on the pyrolysis conditions and can be further enhanced through functionalization. In this study, wheat straw biochar was optimized for enhanced porosity, carbon content, and structural stability and further functionalized by incorporating metal–organic frameworks (MOFs) to create a high-performance nanocomposite. Three MOFs—ZIF-8, UiO-66, and MIL-100(Fe)—were evaluated for their Cu2⁺ and Pb2⁺ adsorption capacities. MIL-100(Fe) emerged as the most effective due to its high pore volume and iron-active sites. Coating biochar with MIL-100(Fe) increased its surface area sixfold, achieving 419 m2∙g−1, and doubled its sorption capacity for heavy metals in soil (142 mmol·kg−1 for Cu2⁺ and 156 mmol·kg−1 for Pb2⁺). Advanced characterization techniques, including XAFS, XRD, and SEM–EDX, revealed that the sorption mechanisms were dominated by complexation and cation exchange, with the nanocomposite demonstrating superior metal immobilization compared to neat biochar. These findings highlight the potential of the nanocomposite as an effective amendment for reducing heavy metal toxicity in soils.

In this study, pervaporation membranes from synthetic biodegradable polyvinyl alcohol (PVA) with improved properties for isopropanol dehydration were developed through modification with a synthesized In(BTC) metal–organic framework. The improvement in the PVA membrane properties was achieved by varying the In(BTC) concentration (2.5–7 wt.%) in the PVA matrix to allow us to select the optimal concentration for the membrane, which was further chemically cross-linked with maleic acid to increase the resistance, and developing a cross-linked supported membrane from the optimal PVA/5%In(BTC) composite for promising industrial applications. The synthesized In(BTC) and membranes were characterized by using spectroscopic, microscopic, X-ray diffraction, and thermogravimetric analysis methods, as well as swelling degree, contact angle measurements, and the Brunauer–Emmett–Teller adsorption model. The obtained regularities were confirmed by quantum chemical calculations. The cross-linked supported membrane from PVA/5%In(BTC) had optimal transport properties for isopropanol dehydration (20–90 wt.% water), 99.9–89.0 wt.% water in the permeate, and 0.142–0.341 kg/(m2h) of permeation flux, the rate of which was four times higher compared to the PVA membrane in separating 20–30 wt.% water/isopropanol.

A cell for conducting operando measurements of X-ray absorption spectra for gas-sensitive sensors based on ZIF-8/ZIF-67 nanofilms is developed and fabricated. The cell is made of stainless steel, which makes it possible to study, among other things, corrosive gases. The possibility of heating and continuous measurement of the sensor temperature during an operando experiment to evaluate the dynamics of sorption in the processes of heating/cooling the cell. The isolated sensor holder has contacts for measuring the capacitance/resistance of the sensor. To measure X-ray absorption spectra for gas-sensitive gas-sensor materials, an X-ray transparent window is provided. For sensors based on ZIF-8 and ZIF-67 nanofilms, the X-ray absorption spectra are measured for the K edges of Zn and Co, respectively. It is found that after exposure to NO2 in a gas-sensitive material based on ZIF-8/ZIF-67 nanofilms, long-range order is lost and the film undergoes amorphization. The X-ray absorption spectra measured for a gas-sensitive material based on ZIF-8/ZIF-67 nanofilms before and after exposure to NO2 indicate a change in the local atomic and electronic structures near cobalt atoms.

The purpose of this research was to investigate the impact of pyrolysis temperature on the properties of biochars fabricated by sewage sludge. Increasing pyrolysis temperature from 300 to 900°С led to an increase of biochar pH between 8.4–11.8, ash content 60–75

Herbicides are pivotal in modern agriculture, efficiently managing weeds and supporting sustainable farming. One of such herbicides is 2,4-dichlorophenoxyacetic acid (2,4-D), a synthetic auxin that targets broad-leaved weeds. It's praised for controlling various weeds with minimal injury to monocot plants. Innovative delivery methods for 2,4-D, like slow release and targeted systems, offer benefits such as extended herbicide release and reduced environmental impact. This review assesses diverse 2,4-D delivery systems: biochar, silica, layered inorganic materials, polymers, and gels, analyzing their benefits and limitations. Success in these systems relies on finding the optimal balance between strong herbicide bonding for high loading efficiency and the controlled release necessary for the desired herbicidal action. Porous materials adapt porosity for this equilibrium, and organic formulations optimize bonding groups. Layered materials, especially hydroxide ones, show potential by attracting 2,4-D anions. Controlled release is critical; Si-based systems achieve pH-controlled release, while polymers rely on hydrolysis modulated by temperature and acidity. Moreover, light-responsive groups offer precise control over 2,4-D distribution via irradiation. These studies highlight how inventive materials and techniques can transform agrochemicals. Ongoing research and development in this field will further enhance the efficiency, sustainability, and safety of herbicide delivery, benefiting agricultural practices and environmental stewardship.

Prototypes of gas sensors with sensitive elements are made based on ZIF-8 and ZIF-67 films obtained directly on a substrate by immersion. The sensitivity of the prototypes to NO2 and CO is assessed by simultaneously analyzing the capacitive and resistive response. It is shown that the functionalization of ZIF-8 films with layers of ZIF-67/ZIF-8 leads to an increase in the sensitivity of the sensor to NO2 by more than 2 times compared to ZIF-8 films, and also allows CO detection. A sensor prototype based on ZIF-67/ZIF-8 films shows a resistive and capacitive sensitivity to NO2 of 3 and 6

The process of the formation of gas-sensitive nanofilms ZIF-8 and ZIF-67 on substrates, which are glass chips with contact tracks formed on them, is studied. Multilayer ZIF-8/ZIF-67 nanofilms are grown on a substrate by cyclic layer-by-layer coating in solution. The film growth process is monitored after each cycle using X-ray diffraction, elemental analysis, and scanning electron microscopy. It is shown that at least three 30-minute growth cycles are required to form a strong, uniform ZIF-8 film. Additionally, the sensory properties of the obtained samples for the detection of carbon monoxide CO are studied.

To evaluate the environmental concerns associated with heavy metals (HMs) during their translocations in food chains, it is crucial to gather data on the types of HMs present in soils in order to ascertain their toxicity and potential to migrate. An overview of the findings from several physical techniques used to determine and identify the HMs, sediments, individual minerals, and organic components in contaminated agricultural and industrial soils, is provided in this review article. These studies cover a variety of X-ray-based analytical techniques, including most widely used ones like X-ray absorption near edge structure, extended X-ray absorption fine structure, X-ray diffraction, and less popular ones X-ray fluorescence, etc. When compared to techniques that rely on laboratory radiation sources, synchrotron radiation offers more precision and efficiency. These methods could pinpoint the primary mechanisms influencing the soil's ability to transport contaminants and track their subsequent migration up the food chain.

Plant hormones have been well known since Charles Darwin as signaling molecules directing plant metabolism. Their action and transport pathways are at the top of scientific interest and were reviewed in many research articles. Modern agriculture applies phytohormones as supplements to achieve desired physiological plant response. Auxins are a class of plant hormones extensively used for crop management. Auxins stimulate the formation of lateral roots and shoots, seed germination, while extensively high concentrations of these chemicals act as herbicides. Natural auxins are unstable; light or enzyme action leads to their degradation. Moreover, the concentration dependant action of phytohormones denier one-shot injection of these chemicals and require constant slow additive of supplement. It obstructs the direct introduction of auxins. On the other hand, delivery systems can protect phytohormones from degradation and provide a slow release of loaded drugs. Moreover, this release can be managed by external stimuli like pH, enzymes, or temperature. The present review is focused on three auxins: indole-3-acetic, indole-3-butyric, and 1-naphthaleneacetic acids. We collected some examples of inorganic (oxides, Ag, layered double hydroxides) and organic (chitosan, organic formulations) delivery systems. The action of carriers can enhance auxin effects via protection and targeted delivery of loaded molecules. Moreover, nanoparticles can act as nano fertilizers, intensifying the phytohormone effect, providing slow controlled release. So delivery systems for auxins are extremely attractive for modern agriculture opening sustainable management of plant metabolism and morphogenesis.

Rare-earth-doped nanoscaled BaGdF5 is known as an efficient contrasting agent for X-ray micro-CT and NMR as well as a promising candidate for X-ray photodynamic therapy, thereby opening an opportunity for theragnostic applications. Conventional synthesis of Ln-doped BaGdF5 consider a long-lasting batch procedure, while a conjugation with photosensitizer usually implies a separate stage requiring active mixing. To the best of our knowledge, in this work, we for the first time obtain BaGdF5:Tb3+ nanophosphors in a microfluidic route at temperatures as low as 100 °C while decreasing the time of thermal treatment down to 6 min. The proposed synthesis route allows for the obtaining of single-phase and monodisperse BaGd1−xF5:Tbx3+ nanoparticles with an averaged particle size of ca. 7–9 nm and hydrodynamic radius around 22 nm, as estimated from TEM and DLS, respectively. In addition, X-ray-excited optical luminescence has been recorded in situ for the series of nanophosphors synthesis with varied flow rates of Tb3+ and Gd3+ stock solutions, thereby anticipating a possible application of microfluidics for screening a wide range of possible co-dopants and reaction conditions and its effect on the optical properties of the synthesized materials. Moreover, we demonstrated that BaGd1−xF5:Tbx3+@RoseBengal conjugates might be obtained in a single-stage route by implementing an additional mixer at the synthesis outcome, namely, by mixing the resulting reaction mixture containing nanoparticles with an equivalent flow of photosensitizer aqueous solution. In vitro cytotoxicity test declares moderate toxicity effect on different cell lines, while the results of flow cytometry indirectly confirm cellular uptake. Finally, we report long-term biodistribution monitoring of the synthesized nanocomposites assessed by X-ray micro-CT in the in vivo experiments on balb/c mice, which depicts an unusual character of agents’ accumulation.

The population growth tendency leads to an increase in demand for food products, and in particular, products obtained from the processing of plants. However, there are issues of biotic and abiotic stresses that can significantly reduce crop yields and escalate the food crisis. Therefore, in recent years, the development of new methods of plant protection became an important task. One of the most promising ways to protect plants is to treat them with various phytohormones. Salicylic acid (SA) is one of the regulators of systemic acquired resistance (SAR) signaling pathways. These mechanisms are able to protect plants from biotic and abiotic stresses by increasing the expression of genes that encode antioxidant enzymes. However, salicylic acid in high doses can act as an antagonist and have the negative rebound effect of inhibition of plant growth and development. To maintain optimal SA concentrations in the long term, it is necessary to develop systems for the delivery and slow release of SA in plants. The purpose of this review is to summarize and study methods of delivery and controlled release of SA in a plant. Various carriers-based nanoparticles (NPs) synthesized from both organic and inorganic compounds, their chemical structure, impacts on plants, advantages, and disadvantages are comprehensively discussed. The mechanisms of controlled release of SA and the effects of the use of the considered composites on the growth and development of plants are also described. The present review will be helpful to design or fabricate NPs and NPs-based delivery systems for salicylic acid-controlled release and better understating of the mechanism of SA-NPs interaction to alleviate stress on plants.

We report the synthesis of a new effective cobalt-based composite for catalytic reduction of water pollutant - p-nitrophenol. ZIF-67 and its Zn-substituted analog have been used as precursors for the catalyst preparation. Their pyrolysis has resulted in cobalt nanoparticles embedded into N-doped carbon substrates. We have used polyvinylidene fluoride (PVDF) as an additive to ZIF-substrates to produce mesoporous carbon shells on the surface of the catalysts. We have found that PVDF-additive enhanced the catalytic properties of the obtained composite material. Firstly, this additive reduces the total cobalt concentration in the composite by increasing carbon content. Secondly, a porous carbon shell improves the rate of catalytic reactions. According to the experimental data, PVDF additive has allowed us to obtain materials with lower Co-content but with high catalytic activity towards p-nitrophenol reduction.

We report a new one-step room-temperature electrochemical synthesis of gamma-Fe2O3@MIL-88a magnetic composite. Anode from metallic iron was used as Fe-source. We did not use any toxic or hazardous solvents. A careful, comprehensive characterization of the obtained material was applied, including a synchrotron experiment. The gamma-Fe2O3@MIL-88a composite comprised diamond-like MIL-88a crystals of 100-300 nm covered with gamma-Fe2O3 nanoparticles. This component provided a magnetic response to the synthesized material. Moreover, gamma-Fe2O3 nanoparticles boosted semiconductor MOF crystals. As a result, the gamma-Fe2O3@MIL-88a composite demon-strated superior photocatalytic performance toward methylene blue degradation. MIL-88a crystals acted as photo-Fenton catalysts activating H2O2 decomposition with the production of active & BULL;OH radicals. Easy magnetic separation and visible-light activated photocatalytic properties make gamma-Fe2O3@MIL-88a composite a promising system for removing organic dyes from contaminated water according to the photo-Fenton process.

X-ray photodynamic therapy (XPDT) is one of the growing methods for the treatment of deep tumors. Substituted calcium tungstate CaWO4 is one of the potential phosphors for a wide range of photosensitizers. In our work, we studied the possibility of replacing Ca2+ with Tb3+ in the scheelite structure and also the effect of the synthesis method on the particle size distribution. It was found that the synthesis and subsequent morphological differences between the samples lead to different intensities of luminescence. This can be used to improve the characteristics of composites for XPDT.

Current research fields of metal-organic frameworks (MOFs), which are being developed in the last 5-10 years by Russian scientific institutions and universities, are generalized. The review encompasses the design, synthesis, topological description, and prediction of MOF properties, the development of methods for their chemical engineering and modification, their investigation by modern physicochemical techniques, and the creation of functional materials based on porous frameworks (heterogeneous catalysts, highly efficient and highly selective sorbents of the new generation, conducting materials, systems for the target drug delivery).

X-ray photodynamic therapy (XPDT) is aimed at the treatment of deep-located malignant tumors thanks to the high penetration depth of X-rays. In XPDT therapy, it is necessary to use materials that effectively absorb X-rays and convert them into visible radiation-nanophosphors. Rare-earth elements, fluorides, in particular, doped BaGdF5, are known to serve as efficient nanophosphor. On the other hand, the particle size of nanophosphors has a crucial impact on biodistribution, cell uptake, and cytotoxicity. In this work, we investigated various Tb:Gd ratios in the range from 0.1 to 0.5 and optimized the terbium content to achieve the maximum luminescence under X-ray excitation. The effect of temperature, composition of the ethylene glycol/water solvent, and the synthesis technique (solvothermal and microwave) on the size of the nanophosphors was explored. It was found that the synthesis techniques and the solvent composition had the greatest influence on the averaged particle size. By varying these two parameters, it is possible to tune the size of the nanophosphor particles, which make them suitable for biomedical applications.

X-ray photodynamic therapy (XPDT) has been recently considered as an efficient alternative to conventional radiotherapy of malignant tissues. Nanocomposites for XPDT typically consist of two components—a nanophosphor which re-emits X-rays into visible light that in turn is absorbed by the second component, a photosensitizer, for further generation of reactive oxygen species. In this study, BaGdF5 nanophosphors doped with different Eu:Gd ratios in the range from 0.01 to 0.50 were synthesized by the microwave route. According to transmission electron microscopy (TEM), the average size of nanophosphors was ~12 nm. Furthermore, different coatings with amorphous SiO2 and citrates were systematically studied. Micro-CT imaging demonstrated superior X-ray attenuation and sufficient contrast in the liver and the spleen after intravenous injection of citric acid-coated nanoparticles. In case of the SiO2 surface, post-treatment core–shell morphology was verified via TEM and the possibility of tunable shell size was reported. Nitrogen adsorption/desorption analysis revealed mesoporous SiO2 formation characterized by the slit-shaped type of pores that should be accessible for methylene blue photosensitizer molecules. It was shown that SiO2 coating subsequently facilitates methylene blue conjugation and results in the formation of the BaGdF5: 10% Eu3+@SiO2@MB nanocomposite as a promising candidate for application in XPDT.

It is known that the initiation of photodynamic therapy (PDT) in deep-seated tumors requires the use of X-rays to activate the reactive oxygen species generation in deep tissues. The aim of this paper is to synthesize X-ray nanophosphors and analyze their structural and luminescence characteristics to push the PDT process deep into the body. The article deals with BaGdF5:Eu3+, BaGdF5:Sm3+, and BaGdF5:Tb3+ nanophosphors synthesized using microwave synthesis. It is found that the nanoparticles are biocompatible and have sizes 5–17 nm. However, according to the analysis of X-ray excited optical luminescence, BaGdF5:Sm3+ nanophosphors will not be effective for treating deep-seated tumors. Thus, BaGdF5:Eu3+ and BaGdF5:Tb3+ nanoparticles meet the requirements for the subsequent production of nanocomposites based on them that can be used in X-ray photodynamic therapy.

Abstract —The prototype of an apparatus for studying the X-ray fluorescence properties of nanomaterials for X-ray photodynamic therapy is developed. The X-ray fluorescence characteristics of nanomaterials based on gadolinium fluorides are studied. For a series of samples, X-ray fluorescence spectra are obtained in the region of 600–700 nm, which allows the conclusion that such materials are promising for use as components of radiosensitizers for X-ray photodynamic therapy. The data obtained are important for optimizing the characteristics of nanomaterials and for further modification of the parameters of methods for synthesizing new materials for X-ray photodynamic therapy.

Ceria supported nanoparticles (NPs) of noble metals are well-known catalysts for diverse hydrogenation and oxidation reactions [1, 2].Their catalytic activity depends on the dispersion and shape of NPs, support, functionalization, etc.However, the use of high Zsupport and small NPs limits their diagnostics especially in laboratory conditions [3].In this study, we demonstrate a possibility of in situ monitoring the size and surface morphology of Pd/CeO2 catalysts during the growth by using FTIR spectroscopy of adsorbed CO.Ceria NPs used as support were synthesized according to the method described in [4] and impregnated by PdCl2 [3].Then, the material was put into the reaction chamber and heated in a flow of Ar up to 30, 150 or 300 °C (samples Pd-30, Pd-150, Pd-300) for 30 min.A mixture of H2, CO and Ar (2.5, 1 and 46.5 mL/min) was passed through the sample for 1 hour to reduce Pd NPs.XRPD didn't allow distinguishing Pd NPs for all samples (Fig. 1a).This fact could be explained by the small size of synthesized Pd NPs which caused broadening of peaks.Tests of catalytic (procedure described in [3]) shown that CO conversion was 25-70% for all samples at 150 °C even without calcination (in case of Pd-150 and Pd-300) and decreased in row Pd-30>Pd-150>Pd-300.