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Over the recent decades, conducting polymers have received great interest in many fields including microelectronics, energy conversion devices, and biosensing due to their unique properties like electrical conductivity, stability, and simple synthesis. Modification of conducting polymers with noble metals e.g. gold enhances their properties and opens new opportunities to also apply them in other fields like electrocatalysis. Here, we focus on the synthesis of hybrid material based on polyindole (PIN) nanobrush modified with gold nanoparticles and its application towards electrooxidation of ethanol. The paper presents systematic studies from synthesis to electrochemical sensing applications. For the characterization of PIN–Au composites, scanning electron microscopy and X-ray diffraction analyses were used. The electrocatalytic performance of the proposed hybrid material towards alcohol oxidation was studied in alkaline media by cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy techniques. The results show that PIN–Au hybrid can be employed as an effective and sensitive platform for the detection of alcohols, which makes it a promising material in electrocatalysis or sensors. Moreover, the proposed composite exhibits electrocatalytic activity towards ethanol oxidation, which combined with its good long-term stability opens the opportunity for its application in fuel cells.

The XXIst century might be called the Plastic Era. With the continually growing consumption and production, low recycling level, one observes the continuous transformation of the Blue Planet into the Ocean of Plastics. Among various problems related to the presence of synthetic materials in the environment, the ghost nets draw particular attention. They are present in the global ocean due to lost or abandoned fishing gear. Their impact on the environment is represented by the tones of animals caught. Moreover, they are an abundant source of secondary marine microplastic and release a considerable amount of toxic chemical compounds. To resolve this issue, an interdisciplinary approach is needed. Chemical research enables a better understanding of polymer behaviour and their weathering, whereas spectroscopy helps in qualitative analyses and proposes solutions. This paper aims to present the interdisciplinary study of this phenomenon and its broad context, including social awareness but underlines the crucial role of chemical research. One focuses on the basic studies of chemical and physical properties as this knowledge provides the first and essential step to tackle the problem.

Superparamagnetic iron oxide nanoparticles (SPIONs) are widely used for biomedical applications for their outstanding properties such as facile functionalization and doping with different metals, high surface-to-volume ratio, superparamagnetism, and biocompatibility. This study was designed to synthesize and investigate multifunctional nanoparticle conjugate to act as both a magnetic agent, anticancer immunological drug, and radiopharmaceutic for anticancer therapy. The carrier, 166Ho doped iron oxide, was coated with an Au layer, creating core-shell nanoparticles ([166Ho] Fe3O4@Au. These nanoparticles were subsequently modified with monoclonal antibody trastuzumab (Tmab) to target HER2+ receptors. We describe the radiobioconjugate preparation involving doping of a radioactive agent and attachment of the organic linker and drug to the SPIONs’ surface. The size of the SPIONs coated with an Au shell measured by transmission electron microscopy was about 15 nm. The bioconjugation of trastuzumab onto SPIONs was confirmed by thermogravimetric analysis, and the amount of two molecules per one nanoparticle was estimated with the use of radioiodinated [131I]Tmab. The synthesized bioconjugates showed that they are efficient heat mediators and also exhibit a cytotoxic effect toward SKOV-3 ovarian cancer cells expressing HER2 receptors. Prepared radiobioconjugates reveal the high potential for in vivo application of the proposed multimodal hybrid system, combined with magnetic hyperthermia and immunotherapy against cancer tissues.

Lithium-ion batteries are currently one of the most important mobile energy storage units for portable electronics such as laptops, tablets, smartphones, etc. Their widespread application leads to the generation of large amounts of waste, so their recycling plays an important role in environmental policy. In this work, the process of leaching with sulfuric acid for the recovery of metals from spent Li-ion batteries in the presence of glutaric acid and hydrogen peroxide as reducing agents is presented. Experimental results indicate that glutaric-acid application improves the leaching performance compared to the use of just hydrogen peroxide under the same conditions. Obtained samples of leaching residues after mixed inorganic-organic leaching were characterized with Scanning Electron Microscopy, Fourier Transform Infrared Spectroscopy, and X-ray diffraction.

Iron oxide-based nanoparticles have been modified in their core with holmium(III) in an amount affecting only slightly their magnetic properties. Nanoparticles were conjugated covalently with biomolecule of trastuzumab (Herceptin&reg, ), the monoclonal antibody that recognizes cancer cells overexpressing HER2 receptors targeting such nanoparticles to the specified tumor tissues. Systematic studies of Ho3+-doped bioconjugates were carried out as a preliminary step for future replacement of &lsquo, cold&rsquo, Ho with 166Ho radionuclide, emitting &lsquo, soft&rsquo, beta(-) radiation for possible targeted radionuclide therapy. Physicochemical properties of the obtained bioconjugates were subsequently tested for use in magnetic hyperthermia, considered as an effective, low-invasiveness anticancer therapy. With such a system we expect to achieve both: active targeting and multimodal action by simultaneous internal and localized irradiation and magnetic hyperthermia of specific cancers.

Comparative photoelectrochemical studies of cadmium sulfide (CdS) nanoparticles with either hydrophilic or hydrophobic surface properties are presented. Oleylamine organic shells provided CdS nanoparticles with hydrophobic behavior, affecting the photoelectrochemical properties of such nanostructured semiconductor. Hydrophilic CdS nanoparticles were drop-cast on the electrode, whereas the hydrophobic ones were transferred in a controlled manner with Langmuir-Blodgett technique. The substantial hindrance of photopotential and photocurrent was observed for L-B CdS films as compared to the hydrophilic, uncoated nanoparticles that were drop-cast directly on the electrode surface. The electron lifetime in both hydrophilic and hydrophobic nanocrystalline CdS was determined, revealing longer carrier lifetime for oleylamine coated CdS nanoparticles, ascribed to the trapping of charge at the interface of the organic shell/CdS nanoparticle and to the dominant influence of the resistance of the organic shell against the flux of charges. The &ldquo, on&rdquo, transients of the photocurrent responses, observed only for the oleylamine-coated nanoparticles, were resolved, yielding the potential-dependent rate constants of the redox processes occurring at the interface.

The present paper demonstrates the feasibility of application of hybrid material based on polyindole and gold nanoparticles as a low-cost and attractive alternative of electrocatalyst utilized for electrooxidation of potential fuel, such as ascorbic acid (AA) for low-temperature fuel cell technology. Polyindole (PIN) has been deposited electrochemically with and without a hard-template method forming nanobrush with well-defined wires. The PIN nanobrush has been decorated with gold nanoparticles and used for AA oxidation. Hybrid material created within this work offers high surface area, thus increasing the current densities recorded during CV experiments, in comparison to those characteristic of the hybrid created without hard-template. The proposed high-surface-area material is a promising substrate for electrooxidation processes.

Industrialization and the growing consumption of medicines leads to global aquatic contamination. One of the antibiotics widely used against bacterial infections in both human and veterinary medicine is tetracycline. Despite its positive antibiotic action, tetracycline is resistant against degradation, and therefore it accumulates in the environment, including the aquatic environment, creating great health hazards, possibly stimulating antibiotic resistance of pathogenic organisms. In this research, aqueous suspensions of semiconductor nanoparticles CdS were used for photocatalytic activity studies in the presence of methylene blue as a model compound, and finally, in the presence of tetracycline, a broad-spectrum antibiotic widely used against bacterial infections, as well as a live-stock food additive. The mechanism and kinetic rate constants of photocatalytic degradation processes of methylene blue and tetracycline were described in correlation with the energy diagram of CdS nanoparticles.

Efficient electrochemical generation of hydrogen peroxide via oxygen reduction is of great interest for industrial and clean energy applications. In this work, we report the application of conducti ...

Polyindole-CdTe (PIN-CdTe) films were prepared by electropolymerization of indole on Pt electrode followed by electrodeposition of CdTe. The synthesized composites were characterized by Raman spectra, UV-vis absorption spectra and SEM images. Photoresponses and photostability of Pt/PIN-CdTe electrodes were determined in polysulphide solution and compared with results obtained for CdTe electrodes without polymer. It was found, that the photocurrent for Pt/PIN-CdTe electrodes is nearly two fold higher and more stable than for Pt/CdTe electrodes. Raman spectra recorded after photo measurements in polysulphides revealed CdS formation. Energy dispersive X-ray spectra (EDS) indicated that amount of CdS formed was higher for CdTe deposits without polymer.

The results of the influence of electrodeposition conditions on the structural, compositional, optical, and photoelectrochemical properties of CdTe thin films deposited in one-step electrochemical method are presented. The CdTe films were prepared electrochemically from aqueous acidic solution with low ratios of Cd2+ ions to Te(IV) ions concentration. Instead of commonly used TeO2, water-soluble Na2TeO3 was used as a source of tellurium ions. The cathodic deposition of CdTe was performed at different constant potentials from solutions containing different cadmium and tellurium ions concentration. As-deposited CdTe thin films were studied by different analytical techniques. The X-ray photoelectron spectroscopy spectra exhibited CdTe formation on the electrode with some amount of tellurium oxides and cadmium oxides. The best quality CdTe deposits, free of TeO2, were formed in bath containing excess of Cd2+ ions and at the potential of −0.65 V vs. saturated calomel electrode, slightly more positive than Eeq of Cd/Cd2+ system. Structural X-ray diffraction studies revealed polycrystallinity of deposits with the highest content of the (111)-oriented cubic (111) form. Optical band gap energy values were found in the range from 1.36 to 1.6 eV for CdTe films prepared at various synthesis conditions. The preliminary photoelectrochemical studies have shown that the variation of the deposition potential as well as bath composition leads to the formation of p- or n-type CdTe films. As-deposited CdTe films were not stable in polysulfide solution under illumination.

In this work we examined the electrochemical properties of poly(indole-5-carboxylic acid), PIn5COOH. The polymer was produced by electrochemical polymerisation using cyclic voltammetry (CV). It was shown that PIn5COOH is electroactive in aqueous solutions showing two redox processes in acidic solution and one redox process in solutions with pH > 4. The oxidation of catechol (CT) on Pt/In5COOH modified electrodes was investigated by cyclic voltammetry (CV) and rotating disc electrode (RDE) voltammetry. It was established that CT was oxidised only after the oxidation of polymer film was initiated and that polymer significantly enhanced the oxidation and reduction peak currents in comparison with bare Pt electrode. The variation of peak currents (ipa, ipc) as a function of CT concentration was found to be linear up to 6 mM. Experiments with a rotating disk electrode show that the oxidation reaction of catechol occures not only at the polymer/electrolyte interface but also in the polymer film.