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Mixed metal oxide (MMO) nanoparticles (NPs) are hybrids consisting of two or more nanoscale metal oxides. Advantages of MMO NPs over single metal oxides include improved catalytic activity, enhanced electrical and magnetic properties, and increased thermal stability due to the synergy of the different oxide components. This study presents a novel fabrication route for TiO2‐CeO2 NPs enriched with oxygen vacancies using a Haberland‐type gas aggregation cluster source. The NPs, deposited from different segmented Ti/Ce targets under varying O2 addition, were examined with respect to final composition, morphology, and Ti, Ce surface oxidation states. Particle formation mechanisms are proposed for the observed morphologies. Additionally, available O2 during deposition and its impact on the formation of defective sites were investigated. Defective sites in TiO2‐CeO2 NPs were analyzed using transfer to X‐ray photoelectron spectroscopy and transmission electron microscopy without contact to ambient oxygen. The incorporation of Ce to the target exhibits synergistic effects on the synthesis process. Segmented Ti/Ce targets enable the deposition of a broad range of mixed oxide NPs with diverse compositions and morphologies at considerably enhanced deposition rates, which is vital for practical applications. The presented fabrication approach is expected to be applicable for a broad variety of MMO NPs. [ABSTRACT FROM AUTHOR]

In recent years, defective TiO2 has caught considerable research attention because of its potential to overcome the limits of low visible light absorption and fast charge recombination present in pristine TiO2 photocatalysts. Among the different synthesis conditions for defective TiO2, ambient pressure hydrogenation with the addition of Ar as inert gas for safety purposes has been established as an easy method to realize the process. Whether the Ar gas might still influence the resulting photocatalytic properties and defective surface layer remains an open question. Here, we reveal that the gas flow ratio between H2 and Ar has a crucial impact on the defective structure as well as the photocatalyic activity of TiO2. In particular, transmission electron microscopy (TEM) in combination with electron energy loss spectroscopy (EELS) revealed a larger width of the defective surface layer when using a H2/Ar (50 %–50 %) gas mixture over pure H2. A possible reason could be the increase in dynamic viscosity of the gas mixture when Ar is added. Additionally, photoinduced enhanced Raman spectroscopy (PIERS) is implemented as a complementary approach to investigate the dynamics of the defective structures under ambient conditions which cannot be effortlessly realized by vacuum techniques like TEM. [ABSTRACT FROM AUTHOR]

Noble metal/semiconductor nanocomposites have been synthesized using various methods, including precipitation and hydrothermal and electrochemical processes. Among these, the photodeposition method stands out for its simplicity, without the need for high temperatures, redox agents, or complex steps. This method facilitates the control over noble metal nanoparticle size by adjusting parameters such as metal precursor concentration, irradiation time, and power. However, understanding the interaction between solid and liquid interfaces, particularly the role of solution viscosity in the growth process, remains a challenge. This knowledge is crucial for precise control over nanoparticle size and distribution. Our study highlights the influence of viscosity, manipulated through different alcohols, on the formation of Ag nanostructures on TiO2 thin films via photodeposition, offering insights into optimizing nanocomposite synthesis. [ABSTRACT FROM AUTHOR]

Algae biomass could be one of the most important economic values in near future. For this reason, we determined the biochemical compositions and molecular weight profiles (MWPs) of eight macroalgae; Green Algae (Codium fragile, Ulva intestinalis, Chaetomorpha linum, and Codium bursa), Red Algae ( Ellisolandia elongata, Jania rubens, and Amphiroa rigida), Brown Algae (Padina pavonica) collected from different regions in Turkey. The differences measured between biochemical compositions such as ash, lipid, and protein of macroalgae species were statistically significant (P<0.05). The lowest and highest ash, lipid, and protein values of eight macroalgae tested were 30.599 ± 2.739 % (Ulva intestinalis) -81.231 ± 0.527 % (Amphiroa rigida), 0.190 ± 0.063 % (Ellisolandia elongata) -1.764 ± 0.090 % (Chaetomorpha linum), and 2.057 ± 0.093 (Amphiroa rigida) -15.280 ± 0.621 (Chaetomorpha linum). The highest levels of MWP of macroalgae tested were determined in 2532 Da ≥. The lowest levels of MWP belonging to the macroalgae was observed in 2532-13000 Da except for Ulva intestinalis and Padina pavonica belonging to 67000 Da ≤. The values observed 2532 Da ≥ were similar to each other except for Ulva intestinalis. The 13700 - 67000 Da and 2532-13000 Da levels belonging to Ulva intestinalis were higher than those of other tested macroalgae. However, level of Ulva intestinalis (67000 Da ≤) was lower than those of tested macroalgae species, followed by Padina pavonica. In conclusion, biochemical compositions of tested macroalgae can make important contributions to feed formulations and functional foods. In addition, based on our biochemical composition analysis the specific macroalgae species are the most promising algal content for use in different industrial areas such as cosmetics, drugs, and functional foods. [ABSTRACT FROM AUTHOR]

Various methods are developed and used to treat oil‐contaminated water, including mechanical separation, chemical treatment, biological treatment, membrane filtration, and sorption. Oil clean‐up via selective sorption of the oil by an engineered surface is the most accepted technique due to its high removal efficiency and low cost. Here, a multifunctional surface providing highly selective oil sorption and clean‐up capability via the photocatalytic decomposition is proposed. This novel surface is named as the "three‐in‐one (3‐in‐1) surface" since it is composed of 1) a highly photocatalytic layer, 2) micro‐ and nanostructures, and 3) a low surface energy layer. First, the TiO2 photocatalytic layer is prepared by magnetron sputtering. Then flowerlike Ag nanoplates are photocatalytically deposited on the sputtered TiO2 layer. Afterward, a low surface energy layer, poly‐1,3,5‐trivinyl‐1,3,5‐trimethylcyclotrisiloxane (p‐V3D3), is over‐coated on Ag/TiO2 surface by initiated chemical vapor deposition (iCVD) while retaining the topographical features of the surface (micro‐ and nanoscale surface structures). The p‐V3D3/Ag/TiO2 surface demonstrates a high selective adsorption to oil whereas simultaneously it shows extreme repellency to water. The p‐V3D3/Ag/TiO2 surface can also be photocatalytically cleaned up and this may find applications in various technology fields including water treatment, microfluidics, self‐cleaning, and water harvesting. [ABSTRACT FROM AUTHOR]