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Research background. Hydrodistillation is a convenient and economical method to extract essential oils, but this technique has been abandoned due to limited extraction rates. Comparison to conventional hydrodistillation, maceration-mediated hydrodistillation could increase mass transfer and provide better control over the extraction thermodynamics, thereby preserving the aroma constituents and their antioxidant activities. The present study describes a useful and innovative modification of conventional hydrodistillation by introducing a macerating agent Triton X-100 and NaCl as an electrolyte to accelerate mass transfer for better extraction of caryophyllene-rich essential oil from sea buckthorn berries. Experimental approach. The parameters of maceration-mediated hydrodistillation, including the mass fraction of macerating agent, electrolyte concentration and extraction time, were investigated within a wide range of 1−10 %, 1−10 g/100 mL and 3−8 h, respectively, to increase the oil yield (g/100 g). The parameters were optimized according to the desirability approach using response surface methodology. The antioxidant activity of the essential oil obtained under optimal conditions was measured using in vitro antioxidant assays and its aroma profile using gas chromatography with mass spectrometery (GC-MS). Results and conclusions. The optimized parameters for the modified hydrodistillation were observed at 4.22 mL Triton X-100 and 4.03 g NaCl for 5.61 h of extraction time with the essential oil yield of (3.2±0.1) % compared to 2.1 % obtained with conventional hydrodistillation. The essential oil produced by the assisted hydrodistillation was rich in (−)-β-caryophyllene (37.2 %) with good antioxidant activities in terms of free radical scavenging capacity (84.2 %), inhibition of linoleic acid peroxidation (68.2 %) and antioxidant capacity expressed in Trolox equivalents (168 μmol/mL). Novelty and scientific contribution. Triton X-100 can disrupt the cell membrane to release the bioactive compounds, while the NaCl reduces the solubility of the non-polar components of the essential oil in the aqueous phase, which can ultimately improve the extraction yield. The proposed approach can be used with minor modifications with the existing hydrodistillation setups and it seems to be more economical for the extraction of sea buckthorn essential oil without compromising its antioxidant potential or its valuable aroma compounds on an industrial scale.

In the present study, we prepared a SnO 2 -Mn 2 O 3 binary composite thin-film electrode by a single-step solution-based aerosol assisted chemical vapor deposition (AACVD) technique for photovoltaic applications. The grown composite thin films were characterized to determine their properties, such as structure, composition, morphology and band gap by field emission scanning electron microscopy (FESEM), x-ray diffractometry (XRD), Raman scattering, energy-dispersive x-ray spectrometry (EDX), x-ray photoelectron spectroscopy (XPS) and UV-Vis absorption spectrophotometry. The evaluation of photoelectrochemical (PEC) response of as-synthesized SnO 2 -Mn 2 O 3 composite photoelectrode, in comparison to the individual thin films of pristine SnO 2 and Mn 2 O 3 prepared from their respective precursors under the same conditions, engendered a promising improvement in photocurrent density. The synergistic effect between SnO 2 and Mn 2 O 3 , the relevance of ball-like morphology, suitable and tunable energy band gap, and better absorbance under the visible range of light resulted in improved photocurrent of ~6.6 mA cm -2 at +0.7 V versus Ag/AgCl electrode of the binary composite, which was 16.5- and 3.4-fold higher than that of the pure SnO 2 and Mn 2 O 3 , respectively. No apparent photocurrent decrease was observed during prolonged stability measurements for 300 s under one-sun illumination of 100 mW cm -2 . The results confirmed the enhancement in PEC activity due to reduced recombination rate of photoinduced electron-hole pairs and improved interfacial charge transfer between electrode/electrolyte interface, which boost the PEC performance of SnO 2 -Mn 2 O 3 binary composite thin film electrode towards water cleavage.

Experimental approach. The parameters of maceration-mediated hydrodistillation, including the volume of macerating agent per mass of sample, electrolyte concentration and extraction time, were investigated within a wide range of 1-10%, 1-10 g/100 mL and 3-8 h, respectively, to increase the oil yield (g/100 g). The parameters were optimized according to the desirability approach using response surface methodology. The antioxidant activity of the essential oil obtained under optimal conditions was measured using in vitro antioxidant assays and its aroma profile using gas chromatography with mass spectrometery (GC-MS). Novelty and scientific contribution. Triton X-100 can disrupt the cell membrane to release the bioactive compounds, while the NaCl reduces the solubility of the non-polar components of the essential oil in the aqueous phase, which can ultimately improve the extraction yield. The proposed approach can be used with minor modifications with the existing hydrodistillation setups and it seems to be more economical for the extraction of sea buckthorn essential oil without compromising its antioxidant potential or its valuable aroma compounds on an industrial scale.

CaTiO3–TiO2 composite oxide films have been employed, for the first time, as photoelectrodes in photoelectrochemical (PEC) splitting of water. The transparent methanol solutions of Ti(iPro)4 and newly synthesized calcium complex [Ca2(TFA)3(OAc)(iPrOH)(H2O)(THF)3] (1) (where TFA stands for trifluoroacetato; OAc stands for acetate; and iPrOH stands for isopropanol) were utilized for aerosol assisted chemical vapor deposition (AACVD) of the target films. The composite electrodes were deposited on fluorine doped tin oxide (FTO) coated conducting glass substrates at varying deposition temperatures of 500–600 °C. The resulting films were extensively characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, energy dispersive X-ray analysis and scanning electron microscopy. PEC responses of all the composite electrodes were studied under simulated solar irradiation of AM 1.5 G (100 mW cm−2). The CaTiO3–TiO2 photoanode formed at 600 °C showed higher photocurrent density of 610 µA cm−2 at 0.7 V versus Ag/AgCl/3 M KCl reference electrode as compared to the other two electrodes fabricated similarly with only difference of fabrication temperature (i.e., 500 and 550 °C).

Present work reports a single step deposition protocol for the growth of robust, durable and homogenous CeO 2 –TiO 2 composite thin films for the investigation of their photoelectrochemical (PEC) properties. The transparent methanol solution of triacetatocerium (III) hydrate and of tetraisopropoxytitanium (IV) precursors in 1:1 mol ratio was employed in aerosol assisted chemical vapor deposition (AACVD) on FTO substrates at temperatures of 550 and 600 °C in the ambient air. These precursors were converted into their trifluroacetates in situ, under these deposition conditions, for their compatibility in the AACVD procedure. XRD, SEM, EDX and XPS analyses verified the formation of uniformly dispersed crystalline CeO 2 and TiO 2 phases in spherical shaped morphologies and a direct bandgap of 2.6 eV was measured from the UV–Visible spectrophotometry. PEC studies of the composite films revealed that the heterojunction developed between n-type CeO 2 and n-type TiO 2 facilitated the separation and transportation of electrons and holes, leading to a promising photocurrent density of about 1.0 mA cm − 2 and prolonged photo stability measured under one-sun illumination (100 mW cm − 2 ) which is up to 60 min at 0.7 V versus Ag/AgCl. This behavior was further confirmed from electrochemical impedance spectroscopy and Bode phase angle measurements. It was also shown that the films fabricated at 550 °C has higher porosity leading to larger interface contacts and thus was able to generate higher photo activity.

A simple and convenient electric field directed aerosol assisted chemical vapor deposition method is developed for the deposition of morphology and structure controlled thin films of ZnO, CdO and PbO with enhanced visible light photoelectrochemical activity. The films are generated from commonly available metal acetates solution in THF at 400 °C. The FESEM/EDX, X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, UV–Vis spectrophotometry was carried out to investigate morphology, structure, stoichiometry and optical band gap of the fabricated films. The photelctrochemical properties investigated in the presence of 0.1 M Na 2 SO 4 of the as-produced ZnO, CdO and PbO thin films show current densities of 207, 263, 237 and 1.55, 215, 1.67 µA cm −2 in light and dark respectively. These results show a slight improvement in photocurrent density of the films prepared under the influence of electric field as compared to the films deposited in the absence of electric field. This difference may have arisen due to compact structure and uniform morphology created under the influence of electric field.

Cold atmospheric pressure plasma (CAPP) comprises an ensemble of ionized gas, neutral particles, and/or reactive species. Electricity is frequently used to produce CAPP via a variety of techniques, including plasma jets, corona discharges, dielectric barrier discharges, and glow discharges. The type and flow rates of the carrier gas(es), temperature, pressure, and vacuum can all be altered to control the desired properties of the CAPP. Since a few decades ago, CAPP has become a widely used technology with applications in every walk of life. The plasma activated liquid mediums like water, ethanol, and methanol have been merged as novel sterilizers. With recent advancements in material science, particularly work on metal–organic frameworks (MOFs), essential oils, and agricultural technologies, CAPP has become a vital component of these advancements. Likewise, CAPP has been found as a green and benign technology to induce early seed germination and plant development. This review covers the critical components of CAPP, the production of reactive oxygen and nitrogen species, and mechanisms by which CAPP‐based technologies are applied to agricultural products, MOFs, and essential oils. Cold atmospheric pressure plasma (CAPP) comes with high‐energy reactive species. The present monograph explains the workings of CAPP technologies, their salient features, pertinence to MOF synthesis, seed germination/sterilization, and production/preservation of essential oils.

This work describes some general procedures for the synthesis and characterization of monometallic and heterobimetallic single source precursors [Cu2Ti4(O)2(OH)4(TFA)8(THF)6]∙THF (1), [Co2Ti4(μ-O)6(TFA)8(THF)6]·THF (2), [Mg2Ti4(O)2(OH)4(TFA)8(THF)6]∙THF (3), [Mn(dmae)2(TFA)4] (4) and [Sn(dmae)(OAc)]2 (5) and their disposal for the growth of thin films for electrochemical applications. The complexes have been characterized by m.p, elemental analyses, FT-IR, TG/DTG and single crystal X-ray analysis. The precursors (1), (2) and (3) were applied as a single source for the fabrication of CuO-2TiO2 and CoTiO3-TiO2 composites and MgTi2O5 solid solution thin films, whereas film precursor (4) has been applied as a dual source along with Ag(I) acetate for the deposition of Ag-Mn2O3 composite thin film by aerosol assisted chemical vapour deposition (AACVD). The electric field directed aerosol assisted chemical vapor deposition technique (EFDAACVD) was used to make thin films of SnO2, Mn2O3, Fe2O3, NiO, CuO, ZnO, CdO and PbO from precursor (5) and their respective acetates. Further CuPbI3 was synthesized by heating co-precipitated mixture of copper(I) iodide and lead(II) iodide in an evacuated Pyrex ampule at 630 oC. The films of CuPbI3 were decorated by electrophoretic deposition method. The phase purity, particle size and crystallinity of deposited thin films were examined by X-ray powder diffraction (XRPD) and Raman spectroscopy, while X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy and energy dispersive X-ray spectroscopy (EDX) were used to investigate the oxidation states, electronic structure, surface morphology, shape and elemental composition of the involved elements. In the case of mesoporous nanostructure of SnO2 microballs surface area 136 m2 g-1 was determined by BET. The optical band gaps of films were determined by UV-visible spectrophotometry and found to be were 1.8, 3.4, 3.8, 1.2, 2.2, 1.9,0.9,3.2, 2.2, 1.9 and 1.82 eV for Ag-Mn2O3, MgTi2O5, SnO2, Mn2O3, Fe2O3, NiO, CuO, ZnO, CdO, PbO and CuPbI3 films, respectively. The applicability of fabricated CuO-2TiO2 and CoTiO3–TiO2 composite electrodes in electrochemical sensors has been investigated towards the sensitive and selective detection of NO2− ions and dopamine (DA), respectively. The CuO-2TiO2 electrode showed the limit of detection (LoD) of 16.6 nM with the linear range of 10 to 200 μM at +1.0 V due to the oxidation of NO2− ions. The CoTiO3–TiO2 electrode showed good electrocatalytic activity for DA with the (LoD) of 0.083 μM and a linear range of 20 to 300 μM. The SnO2 micro balls provide unique network pores that could be easily penetrated by the electrolyte to give high reversible recycling stability for application in lithium ion batteries. The photoelectrochemical activity (PEC) of Ag-Mn2O3, MgTi2O5, Mn2O3, Fe2O3, NiO, CuO, ZnO, CdO, PbO and CuPbI3 thin films determined by the linear sweep voltammetry (LSV) show photocurrent densities of 3, 0.4, 1.2, 0.12, 0.23, 0.13, 0.23, 0.26, 0.20 and 0.25 mAcm-2 at 0.7 V vs Ag/AgCl/3M KCl, respectively. The improved photoelectrochemical behaviour of Ag-Mn2O3, MgTi2O5, Mn2O3, Fe2O3, NiO, CuO, ZnO, CdO, PbO and CuPbI3electrodes was attributed to the increased photon absorption ability, increased surface area, and more efficient electron/hole transfer which were confirmed by LSV, Chronoamperometery, electrochemical impedance spectroscopy and Mott‐Schottky plot.

Carbon corrosion and platinum dissolution are the two major catalyst layer degradation problems in polymer electrolyte membrane fuel cells (PEMFC). Ceramic addition can reduce the corrosion of carbon and increase the stability of catalysts. Pt/TiO sub(2), Pt/TiO sub(2)-C, Pt/Al sub(2)O sub(3) and Pt/Al sub(2)O sub(3)-C catalysts were synthesized and characterized. Electrochemical surface area of Pt/TiO sub(2)-C and Pt/Al sub(2)O sub(3)-C nanocomposite catalysts was much higher than the Pt/TiO sub(2) and Pt/Al sub(2)O sub(3) catalysts. Peak current, specific activity and mass activity of the catalysts was also determined by cyclic voltammetry and were much higher for the carbon nanocomposites. Exchange current densities were determined from Tafel plots. Heterogeneous rates of reaction of electro oxidation of methanol were determined for all the catalysts and were substantially higher for titania catalysts as compared to alumina added catalysts. Mass activity of Pt/TiO sub(2)-C was much higher than mass activity of Pt/Al sub(2)O sub(3)-C. Stability studies showed that addition of ceramics have increased the catalytic activity and durability of the catalysts considerably.