Pesticides pose a significant threat to nontargeted organisms, and their pervasive use makes avoidance challenging. We employed nitrogen-doped carbon cryogels for the removal of organophosphate pesticides. The materials were synthesized and characterized using SEM, Raman spectroscopy, XPS, and BET analysis. Results revealed mesoporous cryogels with pore diameters ranging from 3 to 13 nm. Interestingly, the specific surface area did not change systematically with increasing nitrogen content. All investigated materials have similar composition and structural disorder. Dimethoate, malathion, and chlorpyrifos removal was investigated under stationary and dynamic conditions. Stationary conditions demonstrated successful removal of aliphatic dimethoate and malathion by all investigated materials. Conversely, the materials with the lowest and highest nitrogen content proved ineffective with aromatic chlorpyrifos. Under dynamic conditions, all materials effectively removed malathion and chlorpyrifos while exhibiting suboptimal performance for dimethoate adsorption. Application of nitrogen-doped carbon cryogels to tap water spiked with pesticides yielded successful results under the same conditions. Toxicity testing of treated samples revealed a consistent decrease in toxicity, indicating that contact with cryogels reduces the initial solution’s toxicity. This result also confirms that material–pesticide interaction does not lead to the formation of more toxic byproducts. The demonstrated efficacy suggests the potential application of these materials in water treatment.

Efficient removal of different pollutants from the environment has become one of the most important challenges of modern society. The nitrogen-doped carbon cryogels were synthesized and characterized using XPS. All investigated materials have similar composition and structural disorder. By analyzing XPS spectra, the content of carbon, oxygen, and nitrogen can be obtained, and the existence of functional groups containing these elements can be detected. Dimethoate, malathion, and chlorpyrifos removal were investigated under stationary and dynamic conditions. Stationary conditions demonstrated successful removal of aliphatic dimethoate and malathion by all investigated materials. Conversely, the materials with the lowest and highest nitrogen content proved ineffective with aromatic chlorpyrifos. Under dynamic conditions, all materials effectively removed malathion and chlorpyrifos while exhibiting suboptimal performance for dimethoate adsorption. The demonstrated efficacy suggests the potential application of these materials in water treatment. The toxicity of these pesticide solutions decreases over time, indicating that more toxic products were not formed.

This study introduces a novel solid-phase extraction (SPE) method utilizing pristine and chemically treated carbon cryogel (CC) as an adsorbent for the isolation and enrichment of estrogen hormones (estrone, 17?-estradiol, and 17?-ethinylestradiol) from water samples. High recovery values (82?95 %) were obtained after optimizing the SPE technique, which included adsorbent mass and chemical treatment, sample volume and pH, and elution solvent type and volume. The developed analytical method, based on SPE coupled with liquid chromatography?tandem mass spectrometry (LC?MS/MS), proves to be selective, efficient, and cost-effective for the determination of selected estrogens. The utilization of self-made cartridges with chemically modified CC produced results comparable to those obtained with commercial cartridges while employing significantly less material. Furthermore, the selectivity of the employed materials contributed to minor matrix effects. The optimized method was successfully applied to analyze estrogen hormones in groundwater, surface water, and wastewater samples, with the results highlighting the importance of monitoring these contaminants in the aquatic environment.

Effective removal of various pollutants from the environment has become one of the most important challenges of modern society. Carbon cryogels doped with nitrogen were synthesized and characterized using FTIR. All investigated materials have similar composition and structural disorder. The application of carbon cryogels doped with nitrogen for adsorption from tap water with the addition of OP pesticides gave successful results in stationary and dynamic conditions. Stationary conditions showed successful removal of aliphatic dimethoate and malathion for all tested materials, but they were less effective for aromatic chlorpyrifos. Under dynamic conditions, all materials effectively removed malathion and chlorpyrifos while showing suboptimal performance for dimethoate adsorption. The demonstrated efficiency indicates the potential application of these materials in water treatment. The toxicity of these pesticide solutions decreases over time, indicating that no more toxic products are formed.

Metal complexes with some Schiff bases, as one of the most widely used groups of ligands, have a wide field of application. In order to find a material with the required optical properties, it is very important to examine the material characteristics as a function of the type of chelating ligand, metal, and the ions present as coligands. In this paper, the synthesis of two new complexes of 2-acetylpyridine-aminoguanidine (L) with zinc(II) and cadmium(II), viz. [Zn(L)(NCO)2] and [{Cd(L)Cl(mu-NCO)}2] is described. Their structural characterization was provided by using SC-XRD. Spectroscopic characterization of these two new complexes and two previously synthesized complexes - [Zn(L)(NSC)2] and [Cd(L)Cl2] are performed. Their phonon structure was determined based on the IR transmission and Raman spectra. The range of Raman modes with significantly increased intensities was registered (1000-1700 cm-1), the same range for all four samples. Also, the registered photoluminescence and energy transfers were analyzed and three photoluminescence peaks (E1, E2, E3) were determined. It was concluded that phonons with significantly increased intensities participate in transitions from the E1 state to the energy levels in the range from E2 to E3. The strength of the peaks was significantly affected by replacing one [Cl]- with the [NCO]- ligand. The addition of the second [NCO]- ligand increases the photoluminescence over the entire measured range. The analysis performed helps to understand the issues related to the electron-phonon interaction. Also, the perspectives for the application of metal complexes with various ligands are expanding.

N-doped TiO2/carbon composites (TiO2/CN) with different nitrogen content, were obtained starting from titanium isopropoxide and glucose, and by varying the amount of melamine, added to starting reaction mixture. For comparison, an undoped sample (TiO2/C) was also prepared. Structural and surface characteristics were determined through scanning electron microscopy, thermogravimetric analysis, elemental analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, X-ray diffraction and nitrogen adsorption-desorption isotherms. The photocatalytic activity of TiO2/CN composites was examined via photocatalytic degradation of methylene blue and multiclass pharmaceuticals from water solution. It was found that N doping of TiO2/carbon composites induced changes in structural and surface characteristics of TiO2/CN composites, improving their adsorption, but decreasing photocatalytic efficiency. Nevertheless, TiO2/CN0.05 composite obtained by the hydrothermal synthesis in the presence of glucose and 0.05 g melamine showed the highest efficiency for removing selected pharmaceuticals and methylene blue from aqueous solutions through the combined processes of adsorption in the dark, and photocatalytic degradation under UV and visible irradiation.

In this study, the influence of boron doping on structural and surface properties of carbon material synthesized by a hydrothermal method was investigated, and the obtained results were compared with the previously published influence that boron has on characteristics of carbonized boron-doped hydrothermal carbons (CHTCB). Hydrothermal carbons doped with boron (HTCB) were obtained by the hydrothermal synthesis of glucose solutions with different nominal concentrations of boric acid. It was found that glucose based hydrothermal carbon does not have developed porosity, and the presence of boron in their structure has insignificant influence on it. On the contrary, additional carbonization increases the specific surface area of the undoped sample, while an increase in boron content drastically decreases the specific surface area. Boron doping leads to a decrease in the amount of surface oxygen groups, for both, hydrothermally synthesized and additionally carbonized materials. Raman analysis showed that the boron content does not affect a structural arrangement of the HTCB samples, and Raman structural parameters show a higher degree of disorder, compared to the CHTCB samples. Comparison of structural and surface characteristics of hydrothermal carbons and carbonized materials contributes to the study of the so far, insufficiently clarified influence that boron incorporation has on the material characteristics.

The influence of the structure type on the boron nitride (BN) properties such as excellent thermal and chemical stability and super hardness is well known. The effect of aluminum addition on four different structure types of boron nitride (wurtzite, h-BN, sphalerite, and rock salt) and its electronic properties have been investigated in our study. Here we present an ab initio study of the B1-xAlxN solid solutions for (x = 0; 0.125; 0.25; 0.375 and 0.5), and corresponding structure-property relationship. Novel structures have been discovered in new Al-rich boron nitride compounds and some of them indicate AlN-BN layer separation. Electronic properties have been studied in great detail using hybrid B3LYP approximation. Present results suggest great diversity of the electronic properties generated by adding aluminum to boron nitride and that by using these predicted modifications in various investigated AlN-BN compounds, one could obtain fine-tuning of the band gap in boron nitride electroceramics.

Abstract In this study, pristine and chemically treated carbon cryogel (CC) was employed as a solid-phase extraction (SPE) adsorbent for the isolation and enrichment of estrogens from water samples. A novel, sensitive, selective, and cost-effective analytical method for the determination of estrone, 17β-estradiol, and 17α-ethinylestradiol, based on solid-phase extraction coupled with liquid chromatography-tandem mass spectrometry (LC-MS/MS), was developed and validated. The SPE procedure was optimized by selecting the appropriate adsorbent mass, the sample volume, the sample pH, and the type and volume of elution solvent. The influence of the chemical treatment of carbon cryogel on extraction efficiency was also studied, and it was shown that HNO3 treatment led to a slight increase in recovery values over untreated CC. High recovery values (82–95%) obtained by the optimized extraction method were comparable with the recoveries obtained by commercial cartridges. Finally, the optimized method was successfully applied to the analysis of selected hormones in groundwater, surface water, and wastewater samples. The matrix effect of all tested water types was negligible, indicating the high adsorbent selectivity of examined materials toward observed hormones.

In this study carbon cryogel, cryogel doped with nitrogen, and both nitrogen and sulfur co-doped carbon cryogels (nominal concentration of nitrogen was in the range 2-10 wt%) were synthesized and used as an adsorbent for the removal of carbamazepine, naproxen, diazepam and diclofenac from water. A batch adsorption kinetics study was performed by determination of contact time influence, the effect of pH, and adsorption isotherms. Structural and morphological analysis showed that there are no changes in turbostratic carbon structure induced by doping/co-doping, but noticeable morphology changes were observed. The presence of both nitrogen and ni-trogen/sulfur were confirmed and results showed low content on the surface, especially for sulfur. Obtained high values of the specific surface area for co-doped samples (up to 1530 m2/g) can be caused by sulfur atoms burning or leaving the material during carbonization. The results of the adsorption kinetics study showed that the adsorption of all pharmaceuticals on all tested samples followed the pseudo-second-order kinetic model. The maximum adsorption capacity obtained from the Langmuir isotherm model is higher for doped (91.28-168.92 mg/g) and co-doped (152.97-488.06 mg/g) samples than for pristine sample (59.75-266.28 mg/g). Calculated adsorption energy values from the Dubinin-Radushkevich model indicate that the possible mechanism was physisorption. Desorption tests that were carried out showed satisfactory reusability for all samples. The favorable adsorption characteristics for the co-doped sample with a higher nominal concentration of nitrogen and sulfur qualifies as a potentially good adsorbent for the removal of pharmaceuticals from water.

Nanoemulsion technique based on Ouzo effect was applied for the fast and simple synthesis of Ag3PO4 at room temperature. X-ray powder diffraction analysis and Raman spectroscopy reviled that synthesized powder was single-phase. Using scanning electron microscopy analysis, it was found that the synthesized Ag3PO4 particles were near-spherical shape with an average diameter of 100 nm. The high value for the specific surface area of obtained powder was measured by Brunauer-Emmet-Teller method. Finally, the Ag3PO4 product was used as a photocatalyst for the photodegradation of crystal violet dye in an aqueous solution. Nanoemulsion strategy procedure provides a simple pathway to obtain a highly efficient single-phase Ag3PO4 photocatalyst.

The ZnS nanoparticles, as starting materials in the present study, were synthesized mechanochemically. Surface modification of the obtained nanoparticles was performed by 3-Mercaptopropyftrimethoxysilane. SEM analysis indicates that modification of ZnS nanoparticles with 3-Mercaptopropyltrimethoxysilane causes the appearance of the quasi core-shell structure. The FIR spectrum analysis was performed by fitting procedure, taking into account the appearance of quasi core-shell structure. Optical and structural characteristics of both ZnS and 3-Mercaptopropyltrimethoxysilanes are revealed on the spectrum. An interference effect modulated by the ZnS phonon properties was also detected. Obtained results indicate that the quasi core-shell structures could be successfully applied in the interferometry.

Carbonaceous solid-phase extraction (SPE) sorbent, efficient in isolation and enrichment of multiclass pesticides and pharmaceuticals from water, was synthesized starting from cheap waste beech sawdust and using KOH as the activated agent. The first step in carbon material preparation was hydrothermal carbonization of the waste beech sawdust. Following hydrothermal treatment, the obtained material was activated, using different amounts of KOH. It was found that applied activation leads to changes in material structure, an increase in specific surface area, and a decrease in the number of surface oxygen groups compared to carbonized sample. SPE procedure of multiclass pesticides and pharmaceuticals from water using activated carbonized beech sawdust (AcSD) was optimized by selecting the appropriate elution solvents, the sample pH, and the sample volume to obtain the highest enrichment efficiency. The optimized SPE procedure was applied for water analysis using different AcSD samples as a sorbent for analyte preconcentration. Activated carbon sorbent, obtained with the highest amount of KOH, showed the highest recoveries regarding the most analytes, which were comparable with the recoveries obtained by commercial cartridges.

In this study, carbon cryogel was used as solid-phase extraction sorbent for the extraction of estrogenic hormones (estrone, 17β-estradiol, and 17α-ethinylestradiol) from water solution. The solid-phase extraction (SPE) method was optimized by choosing an appropriate mass of the sorbent, volume, and initial pH of estrogenic hormone water solution, as well as by choosing an appropriate organic solvent. The concentration of tested hormones after extraction was measured by liquid chromatography coupled with tandem mass spectrometry. Based on the obtained hormone recoveries, the following optimal conditions of the SPE procedure were chosen: 100 cm3 of hormone water solution at initial pH adjusted to 7, 20 mg of the sorbent, the methanol-dichloromethane mixture was used for hormone elution. Recoveries obtained under the optimal conditions ranged from 77 % for estrone, to 86 % for 17β-estradiol, with relative standard deviation from 7,4 to 18 %.

Resorcinol-formaldehyde (RP) cryogels were synthesized by sol-gel polycondensation of resorcinol with formaldehyde and freeze-drying was carried out with t-butanol. Carbon cryogel (CC) was obtained by pyrolyzing RP cryogels in an inert atmosphere to 950 degrees C. Nitrogen doped CCs (CCN) were synthesized by introducing melamine into RF precursor mixture solution to obtain nitrogen concentration 2, 6 and 10 wt.%. Material was characterized by elemental analysis, nitrogen adsorption-desorption measurements, scanning electron microscopy (SEM), Raman spectroscopy, FT-IR Spectroscopy. Cyclic voltammetry (CV) was used to investigate capacitive and electrocatalytic properties. Conductivity measurement was also performed. Elemental analysis results confirmed presence of nitrogen in CCN samples in the range from 0.45 to 1.15 wt.%. Raman spectroscopy of the samples showed increase of D and G peak integrated intensity ratio (I-D/I-G) with nitrogen doping suggesting that the structural disorder as well as edge plane density increase, but according to similar I-D/I-G values for CCN samples, their share is not directly related to the amount of incorporated N. Characterization by nitrogen adsorption showed that overall specific surface and maximum mesopores are achieved in CCN sample with medium nitrogen concentration. Results of cyclic voltammetry experiments demonstrated maximum capacitance for CCN sample with smallest N wt% indicating that narrow pore size distribution and high specific surface area are dominant factors to achieve good capacitive behavior. The relatively low doping level of nitrogen reached in CCN samples may be the reason for the incomplete reduction of oxygen to hydroxide and furthermore it turned out that presence of N in the structure of CC had a negligible effect on the otherwise relatively high conductivity of CC.

The structural and morphological properties of iron-doped mullite powders are the subject of the present study. The powders of undoped and iron-doped mullite in the composition range of 3-15 wt% Fe2O3 were synthesized by a combination of sol-gel and combustion methods. The excess of water and urea were introduced in reaction solutions to enhance the copolymerization of aluminum and silicon species. The results of structural characterization revealed that the synthesized mullite powders were amorphous of a hybrid type. The specific surface area of the undoped mullite powder was 262 m(2) g(-1) with a maximum pore radius (d(p)) of 2 nm classifying it into mesoporous materials. The addition of iron has reduced the specific surface area, while the pore size value remained the same except for the sample with 3 wt% Fe2O3 (S-BET = 278 m(2) g(-1); d(p) = 3 nm). The presence of iron caused lowering the temperature of liquid phase formation, while present urea combusted providing the increase of the temperature locally that caused the sintering and formation of agglomerates of smaller particles. However, the results of the particle size analysis are not straightforward. The values of mean volume diameter (D[3,4]) indicated that the particle size increased to 6 wt% Fe2O3 (123.6 mu m), and then decreased and for the sample with 12 wt% Fe2O3, it was equal to 96.6 mu m. Thus, the added iron contributed to the more uniform particle size distribution. The SEM analysis has also shown the coarse powder particles consisted of the coalesced smaller particles.

This paper explores the applicability of unmodified and chemically modified activated carbon cloths (ACCs) for the removal of estrone, 17β-estradiol, and 17α-ethinylestradiol from water. In order to examine the influence of surface properties on hormone adsorption, chemical modification of ACCs with HNO3, HCl, or KOH was employed. Applied treatments increased the specific surface area and changed the content of oxygen functional groups. Increased content of acidic surface oxygen functionalities enhanced adsorption efficiency up to 30 % and had a more dominant influence on adsorption capacity than specific surface area. Adsorption of estrone, 17β-estradiol, and 17α-ethinylestradiol followed pseudo-second-order kinetic model, while the equilibrium adsorption data fitted well with the Freundlich isotherm model. Calculated mean sorption energy values of 1.4475, 1.3387, and 1.0541 kJ/mol, for E1, E2, and EE2 respectively, indicated that removal of selected hormones was dominated by physisorption mechanism. Obtained Langmuir adsorption capacities, 12.34, 12.66, and 11.11 mg/g for estrone, 17β-estradiol, and 17α-ethinylestradiol, respectively, as well as convenience of manipulation, recommend activated carbon cloth modified with HNO3 as an efficient adsorbent for removing estrogen hormones from the water.

The influence of the locally induced laser heating on MnO nanoparticles were investigated by atomic force microscopy (AFM) and far-infrared spectroscopy (FIR) at room temperature, in the spectral region between 80 and 600 cm(-1). The FIR spectra were analyzed by using Maxwell-Garnet formula, where MnO nanoparticles are modeled as a mixture of homogeneous spherical inclusions in air. Laser induced heating leads to the conversion of the part MnO nanoparticles into the MnO2, Mn3O4 and MnOOH, along with possible formation of elemental Mn on the sample surface.

Modified activated carbon cloth is prepared by mechanochemical modification of viscose rayon carbon cloth. The effects of different milling atmospheres, in the air and inert conditions, were investigated. Changes in kind and number of acidic and basic surface groups on the surface of activated carbon cloth, upon modification, as well as before and after the sorption of arsenic were determined. Higher number of basic groups responsible for the removal of arsenic ions was achieved by modification under inert conditions. Breakage and collapse of cylindrical fibers, decrease of particle sizes, change in the shape and consistency of the particles, as well as increase of microstructural disorder i.e. the loss of turbostratic structure occurred upon milling. pHPZC values increased from 4.46 to 5.04 and 5.77 after the air and inert milling, respectively. Adsorption followed pseudo second order kinetics with chemisorption as rate-controlling step. Langmuir isotherm best fit the equilibrium data and maximum adsorption capacity is 5.5 mg g−1 at a pH value close to 7.0, typical for groundwater. The mechanism of arsenic adsorption onto activated carbon cloth milled in inert atmosphere involved electrostatic and dispersive interactions between arsenic ions and carbon particles in wide pH range (from 2 to 10).

We analyzed and compared the unmodified and three modified zinc oxide nanoplatelet materials. The three components used in zinc oxide modification were the 4,4'-bipyridine and two ruthenium (II) complexes, namely, the trans-[Ru (bpy)(bpyCOO)Cl-2](2-) and cis-[Ru (bpy)(bpyCOO)Cl-2](2-). The obtained results revealed that after modification, ZnO nanoplatelets became smaller and embedded in the materials used for the modification. When ZnO was modified with either of the two ruthenium (II) complexes, the interaction between them led to a higher activity of ZnO. The metal-to-ligand charge transfer that was also detected in the two cases of ZnO nanoplatelets modified with the ruthenium (II) complexes caused significant alteration of the Raman spectrum and consequent changes of the optical properties. Various forms of ruthenium (II) complexes were used in several published studies related to dye-sensitized solar cells and biomedicine. The biomedical applications include, for example, the ATP (adenosine-5'-triphosphate) detection, interaction with human serum albumin, DNA analysis, and cancer detection and treatment. The properties of the ZnO nanoplatelets modified with the two ruthenium (II) complexes presented here indicate that it may be worth exploring if the studied materials are applicable in the dye sensitized solar cells and biomedicine. Possible advantage of our results is that they were obtained at room temperature.