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The conversion of carbon monoxide into organic substances is one of the top topics of modern science due to the development of industry and the climate changes caused by it on the one hand, and the possibility of obtaining an economic effect on the other, as it could allow for partial recovery of fuels. A problem in this regard has always been the low solubility of CO2 in water, which eliminated the possibility of easy converting carbon dioxide into the liquid. The development of research on water critical states revealed the fact that water in a subcritical state has a much higher ability to dissolve gases. And this effect was used to obtain the "liquid synthesis gas" model presented in this paper. Equally important was the selection of an appropriate catalyst that would increase the efficiency of the conversion process by generating hydrogen in the system under the influence of cold plasma. In this work we present the studies of transformation of CO2 dissolved in supercritical water using partially reduced graphite oxide—nanometric titania composite (RGO-TiO2) as catalyst, due to the ability of RGO to generate hydrogen in the water environment (water splitting) under the influence of various physical factors, especially cold plasma. The RGO catalyst was stabilized with titanium oxide to obtain higher activity at lower RGO concentrations in the system. Therefore, research on conversions was preceded by a thorough analysis of CO2 solubility in supercritical water, as well as an analysis of the structural, morphological, and spectroscopic properties of the catalyst. Graphic Abstract General scheme of cold plasma reactor.

The article is devoted to methods of synthesis, the structure, and spectral characteristics of zirconium and hafnium phthalocyaninates with out-of-plane coordinated ligands. The gene­ral scheme for the synthesis of out-of-plane coordinated Zr and Hf phthalocyanines includes obtaining initial dichloride or dihydroxo complexes, which then undergo substitution reactions with -dicarbonyl compounds, hydroxybenzoic, sulfo- and aliphatic carboxylic acids, etc. In the case of polyphenols, which are bidentate ligands, one ligand is coordinated to the central atom of the macrocycle. If -dicarbonyl compounds or carboxylic acids are introduced into the reaction, two ligands are coordinated. The reactivity of the out-of-plane coordinated ligands of Zr and Hf phthalocyanines was also investigated. In all obtained out-of-plane coordinated Zr and Hf phthalocyanines, the ligands are located in the cis position relative to the plane of the phthalocyanine macrocycle. X-ray diffraction, NMR, and UV-Vis spectroscopy have proved this arrangement of ligands. According to the X-ray diffraction data of Zr and Hf dibenzoylmethanato phthalocyanines, the metal atom is out of the plane of the phthalocyanine macrocycle, which itself is not planar. The central atoms are located almost in the middle between the N4 planes of the phthalocyanine macrocycle and the O4 of the extraplanar li­gands. The UV-Vis spectra of out-of-plane coordinated Zr and Hf phthalocyanines in organic solvents have a typical appearance for most metal phthalocyanines, characterized by a B-band of absorption in the region of 335–350 nm, a Q-band at 680-690 nm, and its satellite in the region of 615–620 nm. If the extraplanar ligand is a chromophore (e.g., curcumin or condensed derivatives of dehydroacetic acid), there are additional absorption bands in UV-Vis spectra located between the B- and Q-bands. The influence of the nature of the central metal atoms, ligands and solvents on the fluorescent properties of the out-of-plane coordinated Zr and Hf phthalocyanines was also discussed.

This article is a part of a scientific project focused on obtaining a new type of composite materials that are characterized by singlet oxygen generation upon irradiation with red light, which can be used as antibacterial agents. The composite material is nanoscale graphite oxide (GO) particles covalently bonded to an axially substituted zirconium phthalocyanine complex. For this purpose, two phthalocyanine zirconium complexes, axially mono-substituted with 4-aminosalicylic or 4-aminophthalic acids, were prepared and measured in terms of structure, morphology, and spectroscopic properties. The zirconium phthalocyanines are photosensitizers, and the axial ligands are bridging links connecting the complexes to the GO carrier (due to their terminal amino groups and carboxyl groups, respectively). The axial ligand in zirconium phthalocyanine complexes has a strong influence on the stability and optical properties of composite materials and, consequently, on reactive oxygen species (ROS) generation. In this paper, the effect of composite components (4-aminophthalato or 4-aminosalicylato substituted zirconium phthalocyanine complex as a photosensitizer and graphite oxide as a carrier and modulator of the action of active components) on ROS generation for potential antibacterial use is discussed.

Bioactive glasses are materials which can be used in medicine for regeneration of hard and soft tissues. Their functionalization with active molecules or addition to composites broaden significantly the possible range of glass applications. Hereby, we describe photoactive nanoparticles of CaO-SiO

Superior apatite-mineralization ability of solvothemally-derived bioactive glass solvBG76 in a binary system was achieved. This unique bioactivity was accompanied by bio- and hemocompatibility.

Purpose Resistance to antibiotics is a major problem of public health. One of the alternative therapies is silver - more and more popular because of nanotechnology development and new possibilities of usage. As a component of colloid, powder, cream, bandages, etc., nanosilver is often recommended to treat the multidrug-resistant pathogens and we can observe its overuse also outside of the clinic where different physicochemical forms of silver nanoformulations (e.g. size, shape, compounds, surface area) are introduced. In this research, we described the consequences of long-term bacteria exposure to silver nanoformulations with different physicochemical properties, including changes in genome and changes of bacterial sensitivity to silver nanoformulations and/or antibiotics. Moreover, the prevalence of exogenous resistance to silver among multidrug-resistant bacteria was determined. Materials and Methods Gram-negative and Gram-positive bacteria strains are described as sensitive and multidrug-resistant strains. The sensitivity of the tested bacterial strains to antibiotics was carried out with disc diffusion methods. The sensitivity of bacteria to silver nanoformulations and development of bacterial resistance to silver nanoformulations has been verified via determination of the minimal inhibitory concentrations. The presence of sil genes was verified via PCR reaction and DNA electrophoresis. The genomic and phenotypic changes have been verified via genome sequencing and bioinformatics analysis. Results Bacteria after long-term exposure to silver nanoformulations may change their sensitivity to silver forms and/or antibiotics, depending on the physicochemical properties of silver nanoformulations, resulting from phenotypic or genetic changes in the bacterial cell. Finally, adaptants and mutants may become more sensitive or resistant to some antibiotics than wild types. Conclusion Application of silver nanoformulations in the case of multiple resistance or multidrug-resistant bacterial infection can enhance or decrease their resistance to antibiotics. The usage of nanosilver in a clinic and outside of the clinic should be determined and should be under strong control. Moreover, each silver nanomaterial should be considered as a separate agent with a potential different mode of antibacterial action.

Nanoparticles can interact with the complement system and modulate the inflammatory response. The effect of these interactions on the complement activity strongly depends on physicochemical properties of nanoparticles. The interactions of silver nanoparticles with serum proteins (particularly with the complement system components) have the potential to significantly affect the antibacterial activity of serum, with serious implications for human health. The aim of the study was to assess the influence of graphite oxide (GO) nanocomposites (GO, GO-PcZr(Lys)2-Ag, GO-Ag, GO-PcZr(Lys)2) on the antibacterial activity of normal human serum (NHS), serum activity against bacteria isolated from alveoli treated with nanocomposites, and nanocomposite sensitivity of bacteria exposed to serum in vitro (using normal human serum). Additionally, the in vivo cytotoxic effect of the GO compounds was determined with application of a Galleria mellonella larvae model. GO-PcZr(Lys)2, without IR irradiation enhance the antimicrobial efficacy of the human serum. IR irradiation enhances bactericidal activity of serum in the case of the GO-PcZr(Lys)2-Ag sample. Bacteria exposed to nanocomposites become more sensitive to the action of serum. Bacteria exposed to serum become more sensitive to the GO-Ag sample. None of the tested GO nanocomposites displayed a cytotoxicity towards larvae.

In this study, microbial diversity of the root canal microbiota related to different endodontic infections was investigated. In total, 45 patients with endo–perio lesions (8 patients), chronic periapical periodontitis (29 patients) and pulp necrosis (8 patients) were recruited. In 19 (42.2%) patients there was secondary infection of root canals. Microbial specimens were collected from root canals of non-vital teeth with or without changes in periapical area visible in X-ray. Then, oral microbiota were detected and identified using the culture method and real-time PCR amplification primers and hydrolysis-probe detection with the 16S rRNA gene as the target. Overall, 1434 species/genes from 41 different genera of 90 various microbial species were retrieved. Of the major reported phyla, Firmicutes (62.9%), Actinobacteria (14.0%), Bacteroidetes (12.1%), Proteobacteria (9.1%) and Fusobacteria (4.2%) were detected. Of the bacterial species, 54.6% were strict anaerobes. Corynebacterium matruchotii (p = 0.039) was present significantly more frequently in chronic periapical periodontitis. Moreover, the higher values of Decayed, Missing and Filled Permanent Teeth index were positively correlated with relative abundance of Actinomyces spp. (p = 0.042), Lactobacillus spp. (p = 0.006), Propionibacterium spp. (p = 0.024) and Rothia spp. (p = 0.002). The multivariate analyses revealed differences in total root canal samples, where components that affected grouping of root samples into four main categories were identified. Anaerobic Gram-negative bacteria predominated in root canals of teeth with pulp necrosis and periapical lesions. Facultative anaerobic Gram-positive bacteria predominated in canals with secondary infections. All detected members of mixed population groups that might serve as keystone species contributed to the entire community in its clinical relevance.

We present studies on bioactive silica-based glass nanoparticles showing photoluminescence. The sol–gel or solvothermal route was used for syntheses. Lanthanides, zinc oxide or phthalocyanine complexes ensured light emission. The structural, morphological, and optical properties were examined. During the bioactivity tests, when particles were immersed in SBF, ions release to the medium and hydroxyapatite formation were analyzed. Composites with graphite oxide were described as well. The systems are promissing for monitoring structural changes of the glass immersed in biological fluids, bioimaging or photodynamic therapy. Research was performed within Polish–Ukrainian Joint Exchange Project and NSC grants 2016/23/B/ST5/024830, 2016/22/E/ST5/00530.

A new conjugate of gallato zirconium (IV) phthalocyanine complexes (PcZrGallate) has been obtained from alkilamino-modified SiO2 nanocarriers (SiO2-(CH2)3-NH2NPs), which may potentially be used in photodynamic therapy of atherosclerosis. Its structure and morphology have been investigated. The photochemical properties of the composite material has been characterized. in saline environments when exposed to different light sources Reactive oxygen species (ROS) generation in DMSO suspension under near IR irradiation was evaluated. The PcZrGallate-SiO2 conjugate has been found to induce a cytotoxic effect on macrophages after IR irradiation, which did not correspond to ROS production. It was found that SiO2 as a carrier helps the photosensitizer to enter into the macrophages, a type of cells that play a key role in the development of atheroma. These properties of the novel conjugate may make it useful in the photodynamic therapy of coronary artery disease.

Amyloid fibrils are widely studied both as target in conformational disorders and as basis for the development of protein-based functional materials. The three Zr phthalocyanines bearing dehydroacetic acid residue (PcZr(L1)2) and its condensed derivatives (PcZr(L2)2 and PcZr(L3)2) as out-of-plane ligands were synthesized and their influence on insulin fibril formation was studied by amyloid-sensitive fluorescent dye based assay, scanning electron microscopy, fluorescent and absorption spectroscopies. The presence of Zr phthalocyanines was shown to modify the fibril formation. The morphology of fibrils formed in the presence of the Zr phthalocyanines differs from that of free insulin and depends on the structure of out-of-plane ligands. It is shown that free insulin mostly forms fibril clusters with the length of about 0.3–2.1 μm. The presence of Zr phthalocyanines leads to the formation of individual 0.4–2.8 μm-long fibrils with a reduced tendency to lateral aggregation and cluster formation (PcZr(L1)2), shorter 0.2–1.5 μm-long fibrils with the tendency to lateral aggregation without clusters (PcZr(L2)2), and fibril-like 0.2–1.0 μm-long structures (PcZr(L3)2). The strongest influence on fibrils morphology made by PcZr(L3)2 could be explained by the additional stacking of phenyl moiety of the ligand with aromatic amino acids in protein. The evidences of binding of studied Zr phthalocyanines to mature fibrils were shown by absorption spectroscopy (for PcZr(L1)2 and PcZr(L2)2) and fluorescent spectroscopy (for PcZr(L3)2). These complexes could be potentially used as external tools allowing the development of functional materials on protein fibrils basis.

Two complexes of bis(aminobenzoato)zirconium(IV) phthalocyanine and their graphite oxide-based composites were synthesized and characterized in respect of their photochemical properties. Structures of phthalocyanines were confirmed by Mass and infrared spectroscopies. The absorption and photoluminescence spectra were investigated to show various behavior of the complexes in different media (dimethyl sulfoxide and saline). Optical technique (monitoring variation of absorption spectra of diphenylisobenzofuran used as an indicator) was used to prove the generation of reactive oxygen species (ROS) by under light irradiation in the range of the first biological window. The photoactivity of the materials was compared and discussed in terms of their potential ability to be used in biomedical applications, for example, as photosensitizers in photodynamic therapy.

In this work, the synthesis of a group of photoactive materials based on zirconium(IV) phthalocyanine out-of-plane substituted with two fragments of L-arginine is described. The studied group contained the phthalocyanine (Pc) complex, complex immobilized on graphite oxide (GO) flakes, composite of GO-Pc with silver nanoparticles, and GO-Pc being a component of dental filling cement. The structural, compositional, morphological, and optical properties of the materials were studied using, among others, scanning electron microscopy, X-ray diffractometry, and optical spectroscopies (UV–Vis absorption, FTIR, Raman, and photoluminescence). The photoactivity of all materials was confirmed when they were exposed to broadband red light, observed as reactive oxygen species generation that was the highest for the Pc complex, lower for the GO-Pc samples, and the lowest but still present, in the case of GO-Pc-modified cement. The bioactivity of the GO-Pc and GO-Pc-Ag samples was tested against both Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa) bacteria strains showing the highest action against S. aureus and a slight impact of the light irradiation. The comparison of cytotoxicity tests performed for GO-Pcs with Pc complexes substituted with different ligands showed that the GO with L-arginine derivative of PcZr had the lowest toxicity.

Room temperature FT-IR spectra in the range 30–4000 cm −1 and FT-Raman spectra in the range 80–4000 cm −1 of indium and lutetium MPX-type phthalocyanines have been compared. The assignment of the observed bands has been accomplished on the basis of DFT chemical calculations using the B3LYP functional and its long range corrected version - CAM-B3LYP. The calculations were carried out for the indium derivative using the LANL2DZ, CC-PVDZ basis sets, i.e. the following approximations were used: B3LYP/CC-PVDZ, B3LYP/CC-PVTZ, B3LYP/LANL2DZ, CAM-B3LYP/CC-PVDZ and CAM-B3LYP/LANL2DZ. The molecular structures of these derivatives have been discussed in terms of group theory and geometry optimisation taking into account the shape and number of the bands corresponding to the stretching and bending vibrations of MN 4 coordination polyhedron as well as the whole studied complex. The calculated structural parameters have been related to those from XRD studies. The usefulness of the proposed theoretical approaches in the prediction of the structural and vibrational data were analysed.

Among a wide variety of solid state materials lanthanide beta-diketonates, their derivatives and polymeric materials based on them have become essential for advance technologies. Thus they are the subject of extensive spectroscopic studies. Using appropriate lanthanide chelates for the emission layer one can achieve electroluminescence covering the spectrum from blue to infrared. Moreover, compounds with proper chromophores can be the best way to excite and enhance the emission although the f-f transitions have forbidden character. Two types of new Sm(III) chelates; phosphoro and sulfono-derivatives of beta-diketones and polymeric materials on their base were obtained and characterized by the high resolution photoluminescence spectroscopy at 293, 77 and 4 K, as well as by luminescence decay times. Those new type of phosphors shows strong orange emission after excitation at 404 nm Sm(III) states and 280 nm ligand bands. Radiative transition probabilities were calculated from absorption spectra and Judd- Ofelt parameters evaluated. Effects of the temperature, rigidity of polymeric lattice and the energy of excitation on intensities of the Sm(III) fluorescence were studied. The paths of energy transfer are analysed and mechanism of this process is proposed.

In search of an effective antibacterial agent that is useful in photodynamic therapy, new derivatives of zirconium(IV) phthalocyanine (ZrPc) complexes were obtained and linked to graphite oxide flakes. In the syntheses of ZrPc derivatives, two bis-axially substituted ligands with terminal amino group and different lengths of linear carbon chain (C4 in 4-aminobutyric acid or C11 in 11-aminoundecanoic acid) were used. The optical properties (absorption and photoluminescence spectra) of ZrPcs and the composites were examined. Broadband red&ndash, near-infrared lamp was tested as an external stimulus to activate ZrPcs and the composites. Optical techniques were used to show generation of singlet oxygen during irradiation. Considering the application of graphite oxide-based materials as bacteriostatic photosensitive additives for endodontic treatment of periapical tissue inflammation, the antibacterial activity was determined on one Escherichia coli strain isolated directly from an infected root canal of a human tooth and one strain with silver and antibiotic resistance. Looking at the obtained results, modified levels of activity toward different bacterial strains are discussed.

We studied magnetostatic response of the Bi0.9La0.1FeO3-KBr composites (BLFO-KBr) consisting of nanosized (about 100 nm) ferrite Bi0.9La0.1FeO3 (BLFO) conjugated with fine grinded ionic conducting KBr. When the fraction of KBr is rather small (less than 15 wt percent) the magnetic response of the composite is very weak and similar to that observed for the BLFO (pure KBr matrix without Bi1-xLaxFeO3 has no magnetic response as anticipated). However, when the fraction of KBr increases above 15percent, the magnetic response of the composite changes substantially and the field dependence of magnetization reveals ferromagnetic-like hysteresis loop with a remanent magnetization about 0.14 emu/g and coercive field about 1.8 Tesla (at room temperature). Nothing similar to the ferromagnetic-like hysteresis loop can be observed in BLFO ceramics, which magnetization quasi linearly increases with magnetic field. Different physical mechanisms were considered to explain the unusual experimental results for BLFO-KBr nanocomposites, but only those among them, which are highly sensitive to the interaction of antiferromagnetic Bi0.9La0.1FeO3 with ionic conductor KBr, can be relevant. An appropriate mechanism turned out to be ferro-magneto-ionic coupling., 24 pages, 4 figures in the main text, and supplement with 4 figures

High energy photons (UV) are not efficiently utilized in the organic solar cells mainly due to the negative impact on long term stability and the high absorption coefficient of flexible substrate and transparent electrodes. Powder of nanocrystalline strontium cerium oxides (Sr 2 CeO 4 ) was used for fabrication of thin luminescent layers. The down-shifting properties of Sr 2 CeO 4 could improve the stability of organic solar cell without significant losses of short-circuit current. Various design aspects associated with deposition of thin films and their luminescent properties are discussed. The measurement method allowed for determining the down-shifting properties (in the qualitatively way) of fabricated samples which were placed on the top of organic solar cells with the P3HT:PCBM bulk heterojunction.

International audience; Lanthanide complexes with phthalocyanines (Pc) and porphyrins are of great interest because of their unique luminescence behavior and many applications. Our research is devoted to photophysical studies and theoretical calculations HF and DFT of the structure and spectroscopy of two dimeric systems, created by chloro Yb(III) monophthalocyanines and comparison of the calculated spectroscopic behaviour with the experimental one for monomeric chelate in polymeric lattice of PMMA.Ytterbium chelates were chosen because they have special properties appropriate for technology of different materials with unique spectroscopic behaviour in NIR region, which is not overlapped by very intensive emission of π-conjugated system of phthalocyanine or by upconversion transitions.The drastic variation in emission properties of materials depend on the energy of excitation, and only minor changes are observed in spectroscopic frequencies of dimeric systems compared to monomeric ones. Attention is paid to the radiative, non-radiative and non-linear processes, intramolecular energy transfer and the role of charge-transfer state in this process.

The irradiation of ZnSe:Yb polycrystalline ceramics by focused beam of a CW 975 nm laser diode in vacuum conditions leads to generation intense white light in visible range. The emission band was centered at 630 nm. The intensity of white emission increased exponentially with the power density of incident laser light. The influence of excitation power density on generation of broadband emission was investigated. It was found that with increasing excitation power density the total intensity and the slope of exponential enhancement of white light significantly increase. Moreover, for the highest excitation power density there appeared by excitation threshold. The impact of excitation density on white laser induced white emission (LIWE) was discussed in terms of multiphoton excitation and avalanche ionization

This paper presents a short review of the results obtained by the authors in the field of the sol–gel-derived glass nanoparticles activated with lanthanides ions. The attention is focused on the systems that are particularly interesting for photonic structures and bioapplications. We discuss how the sol–gel technology allows to prepare different kind of active nanoparticles and how is possible to use them in specific applications. Some examples showing fabrication techniques of spherical micro- and nanoparticles are given, including preparation of rare-earth-doped silica and silica-calcia glass. The proper structures are mentioned to tailor the optical and spectroscopic properties of microresonators. Glass-ceramics systems are also reminded where nanocrystalline particles are derived. Fabrication and spectroscopic assessment of rare earth doped HfO2 and SnO2 nanoparticles are presented as well. Finally, it is discussed how bioactive properties of SiO2– CaO nanoparticles can be used in medicine, for example in tracking using their luminescent properties.

Laser induced white light emission was observed from porous graphene foam irradiated with a focused continuous wave beam of the infrared laser diode. It was found that the intensity of the emission increases exponentially with increasing laser power density, having a saturation level at ca. 1.5 W and being characterized by stable emission conditions. It was also observed that the white light emission is spatially confined to the focal point dimensions of the illuminating laser light. Several other features of the laser induced white light emission were also discussed. It was observed that the white light emission is highly dependent on the electric field intensity, allowing one to modulate the emission intensity. The electric field intensity ca. 0.5 V/μm was able to decrease the white light intensity by half. Origins of the laser-induced white light emission along with its characteristic features were discussed in terms of avalanche multiphoton ionization, inter-valence charge transfer and possible plasma build-up processes. It is shown that the laser-induced white light emission may be well utilized in new types of white light sources.

Dentists practice shows, that in the process of treatment of root canal treatment, quite often the secondary infection of canal takes place. This problem, on the one hand, can be caused by inaccurate purification (disinfection) of canals, untight fulfillment of canal, or incidence of bacterial strains (especially anaerobic) in the canals, which are resistant to conventional disinfectants and antiseptics therapy (Sundqvist G, Figdor D, Persson S, Sjogren U Oral Surg Oral Med Oral Pathol Oral Radiol Endod 85:86–93, 1998). In order to solve this problem, we realize the following tasks: (i) from the clinical point – collecting of biopsy bacterial strains from root canals of patients, (ii) from the microbiological point – identification of bacterial strains, measurement of their microbiological characteristics (which shows, among other, the resistance of bacteria to antibiotics), and carrying out for this strains and the corresponding commercial strains a comprehensive study of the antimicrobial activity of the studied composite materials, (iii) from the physical point – identification and explanation the effects of light on antibacterial activity of the composite material, (iv) from the material science point – development of canal-filling materials doped with composites, including the measurement of their antimicrobial activity. The final step of investigation should be experimental clinical studies of the developed cements (doped with composites) on biopsy materials.

In the matter of white light (WL) generation, considerable scientific interest has been recently devoted to the studies of carbon materials where laser light or electrical current are used for incandescence or light emission. Experiments have been performed on a number of structures, including carbon nanotubes, fullerenes, graphene, and graphene QDs, which are being considered as materials for next-generation light sources. The studies on WL emission of graphene-based materials (foam and ceramic) are presented. The intense broad band white lighting was observed in vacuum under a focused beam of laser irradiation at a number of different excitation wavelengths, from the VIS to the NIR range. It was observed that the WL emission from graphene materials was a threshold process exhibiting supralinear behavior. The intensity was highly dependent on the ambient pressure. Relatively low temperature of the sample was measured that did not exceeded 600 °C. The luminescence process was accompanied by efficient photoconductivity that increased with excitation power of the laser. The possible mechanism of white light generation is discussed as a photoinduced, transient, domain-like sp2→sp3phase transitions.

The axially substituted monophthalocyanine complexes of lanthanides are not enough investigated in comparison with sandwich-type phthalocyanine complexes of lanthanides because of their much lower stability in comparison with sandwich-type complexes. In this work, the new methods of obtaining monolithic silica blocks doped with acetato substituted Yb(III) monophthalocyanine complex are reported. The spectroscopic properties of this complex were measured and the results were compared for solution, solid state and xerogels dotted with PcYb(OAc). Besides of the usually observed emission of the phthalocyanines, the emission of the Yb3+ ion in IR region after excitation in phthalocyanine band (674 nm) for Yb(III) complex incorporated in silica gel was observed first time. Thus, this result confirms energy transfer in the system under study. The mechanism of energy transfer was proposed. It is worth to notice, that Yb(III) emission was not observed for complex in solution and at solid state. The IR and Raman spectra of ytterbium ion in phthalocyanine complexes are reported and discussed.

The structure of the complex of 5-sulfasalicilato zirconium (IV) phthalocyanine was studied with 1D, 2D 1H NMR and 1H–14N NMR spectroscopy and electro spray ionization mass spectrometry (ESI-MS). The computer models of this complexes was created with program HyperChem 7.0. The strong correlation between geometrically optimized molecule structure and location of characteristic signals in NMR spectra was observed. The ability of the metal in this complex for extra coordination of solvent molecules was confirmed by ESI-MS spectra and computer optimization of the structure of this complex with extra coordinated solvent ligand. Also the type of dimerization of complexes in water solution, that was confirmed by UV–Vis absorption and emission spectra, was founded with the aid of computer energy optimization of geometry of dimer system.

Ca1−xEuxAl4O7 (x = 0, 0.002, 0.01, 0.02, 0.05, 0.1) and Ca1−2xEuxNaxAl4O7 (x = 0.002, 0.02, 0.05, 0.1) crystalline phosphor powders have been synthesized by modified Pechini method and their spectroscopic properties at room and liquid nitrogen temperature were measured. Excitation spectra of synthesized materials contain broad band attributed to ligand to metal, O2−→Eu3+, charge transfer absorption and narrow lines related to 7F0→5DJ, 5HJ, 5LJ, 5GJ transitions of europium ions. Upon excitation at 395 nm, the Eu3+-doped calcium dialuminates exhibit red photoluminescence due to parity forbidden f–f intra-configurational transitions with the most intense component at 612 nm resulting from the 5D0→7F2 hypersensitive transition. The quantum efficiency of the powders emissions does not exceed 12%. The luminescence decay kinetics reveals that some quenching appears for higher concentrations. Site selective spectroscopy disclosed the presence of at least two well defined individual spectroscopic sites of Eu3+ and increasing disturbance of their local symmetries with raising concentration of the activator was observed. The increasing symmetry disorder led to a significant asymmetrical broadening of the luminescence lines at higher concentrations. Concentration dependence of the luminescence kinetics of the two diverse Eu3+ ions is different, as only one of them, with the characteristic luminescence at 579.5 nm, exhibits shortening of the decay time at higher Eu contents. The inexpensive CaAl4O7:Eu powders are potentially good candidates for photonics applications. For Eu, Na co-doped powders the Eu3+ ions producing emission at 579.7 nm dominates strongly over those with luminescence at 577.2 nm.

A new conjugate material based on partially reduced graphite oxide (rGO), silver nanoparticles (Ag), and bis(lysinato)zirconium(IV) phthalocyanine complex (ZrPc) was obtained. Its optical properties (absorption and photoluminescence) after dispersion in solvents were examined. The antimicrobial properties were tested to determine the effect of the composite on the following bacterial strains: Staphylococcus aureus , Pseudomonas aeruginosa , and Escherichia coli , which are responsible for many infections and are one of the pathogens the most difficult to treatment. The results obtained for rGO–ZrPc–Ag composite were compared with the properties of GO, GO–ZrPc, and rGO–Ag structures. The influence of the near-infrared irradiation on the antimicrobial activity of ZrPc- and Ag-doped materials against bacteria was observed for very low concentration (0.32 mg/mL) of GO–ZrPc to stop the growth of P. aeruginosa in comparison to the nonirradiated sample (41 mg/mL). The usefulness of this material in therapy, such as wound infection treatment or endodontic treatment, as antibacterial agent with sustained action was discussed.

The monolithic silica gels with incorporated phthalocyanine complexes of metals is the good model system for investigations on phthalocyanine based laser, optical waveguides, for searching of photovoltaic effects of phthalocyanine complexes, for investigations on cytostatic activity of this complexes in photodynamic therapy of cancer and as biosensors. The difficulty of obtaining of phthalocyanine dotted transparent monolithic silica gels without chemical changes of phthalocyanine ring and with retaining of stability of metal-phthalocyanine complexes in conditions of gel-formation reactions caused, that most of articles about silica gels, dotted by phthalocyanines are concentrate on metal phthalocyanine complexes with lateral substitutors in phthalocyanine ring (such as aluminum or zinc tetrasulfophthalocyanine), or on sandwich type compounds, in case of phthalocyanato lanthanide complexes. The monolithic transparent silica gel blocks dotted with axially substituted monophtalocyanine complexes of Zr (IV), Hf(IV), Er(III), Tm(III) and Yb (III) were obtained. Stability of complexes in gels on different stages of gel formation was provided by absorption spectra. The influence of silica matrix to absorption and emission spectra of metal monophthalocyanine complexes was investigated in comparison with spectra of these complexes in solid and DMSO solutions.