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The Fe‐Pd bifunctional heterogeneous electro‐Fenton catalyst is an attractive option for the degradation of phenol wastewater. However, the catalyst faces issues such as inadequate yield of H2O2 on the Pd species and poor durability. In this study, we developed a bifunctional Fe‐Pd catalyst with Zn embedded into a mesh‐type γ‐Al2O3/Al support (ZnxFePd/γ‐Al2O3/Al). The characterization results indicate that the addition of Zn can improve the dispersion of the Pd component on the catalyst surface and promote the crystallization of Fe3O4. Density functional theory calculations reveal that Zn doping reduces the activation energy of the rate‐controlled step and promotes the desorption of products and intermediates in H2O2 synthesis. The reaction kinetics model was proposed. Furtherly, a possible reaction mechanism was proposed to explain the phenol degradation pathways. The selected Zn1.4FePd/γ‐Al2O3/Al catalyst achieved a degradation rate of 98.8% for phenol. The degradation rate remained above 85% after seven cycles. [ABSTRACT FROM AUTHOR] more...

Zn is a frequently used and sometimes even an inevitably involved element (when zeolitic imidazolate framework-8 (ZIF-8) is adopted as the precursor) for preparing high-performance Fe-N-C oxygen reduction reaction (ORR) catalysts. However, how the Zn element affects the physicochemical architecture of the catalysts, how it enhances the catalytic activity and whether Zn atoms serve as the active centers remain unclear. Herein, we proposed a novel route that adopted pyrrole as the precursor and flexibly controlled the addition of exogenous Zn and Fe dopants before pyrrole polymerization. In this way, a series of nitrogen-carbon catalysts with or without Zn or Fe doping were synthesized. The detailed characterization revealed the role of Zn and Fe doping in the catalyst morphology, pore structure, active site configurations, ORR catalytic activity and fuel cell performance. Importantly, the findings revealed that Zn doping has little effect on the ORR mechanism and pathway. It enhances ORR activity primarily by increasing the number of active sites via introducing more micro- and meso-pores, rather than by creating new active sites. While Fe doping participated in forming both pores and active site centers. Moreover, the catalyst that co-doped with Zn and Fe atoms (Zn-FeNC), synthesized via this simple and template-free route we proposed, presented a unique hollow and hierarchical pore structure with highly boosted ORR activity. It exhibited a 40 mV higher E1/2 value than Pt/C in alkaline media, along with a rapid current response in air-cathode of the direct formate fuel cell. These results are valuable in guiding the synthesis of high-performance Fe-N-C catalysts. [ABSTRACT FROM AUTHOR] more...

The bimetallic nickel-cobalt phosphide (NiCoP) has been confirmed as an efficient electrocatalyst in water splitting. But little attention is paid to the selectivity and affinity of metal sites on hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, we report a trace-Zn-doping (2.18 wt.%) NiCoP (Zn-NiCoP) whereby the nanoparticles self-aggregated to form elongated nanoneedles. We discover that both Co and Ni sites can be replaced by Zn. The Co substitution improves HER, while the Ni substitution dramatically reduces the energy barrier of the rate-determining step (*O → *OOH). The negative shift of d-band centers after Zn doping ameliorates the intermediate desorption. Therefore, Zn-NiCoP demonstrates superior electrocatalytic activity with overpotentials of 48 and 240 mV for HER and OER at 10 and 50 mA·cm−2, respectively. The cell voltage with Zn-NiCoP as both anode and cathode in water splitting was as low as 1.35 V at 10 mA·cm−2. [ABSTRACT FROM AUTHOR] more...

We proposed a new strategy for CO2 hydrogenation to prepare light olefins by introducing Zn into GaZrOx to construct ZnGaZrOx ternary oxides, which was combined with SAPO‐34 to prepare a high–performance ZnGaZrOx/SAPO‐34 tandem catalyst for CO2 hydrogenation to light olefins. By optimizing the Zn doping content, the ratio and mode of the two–phase composite, and the process conditions, the 3.5 %ZnGaZrOx/SAPO‐34 tandem catalyst showed excellent catalytic performance and good high–temperature inhibition of the reverse water–gas shift (RWGS) reaction. The catalyst achieved 26.6 % CO2 conversion, 82.1 % C2=−C4= selectivity and 11.8 % light olefins yield. The ZnGaZrOx formed by introducing an appropriate amount of Zn into GaZrOx significantly enhanced the spillover H2 effect and also induced the generation of abundant oxygen vacancies to effectively promote the activation of CO2. Importantly, the RWGS reaction was also significantly suppressed at high temperatures, with the CO selectivity being only 46.1 % at 390 °C. [ABSTRACT FROM AUTHOR] more...

Copyright of Journal of Synthetic Crystals is the property of Journal of Synthetic Crystals Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Sodium ion batteries (SIBs) are promising technique for energy storage applications. Cathode materials are keys to improve the energy density of SIBs. P2-type layered cathodes with low Na ion diffusion barrier attract great attention. However, it suffers structural instability at a high working voltage. Though many attempts were made, the cycle stability of P2-type layered cathodes with a high working voltage is still not satisfactory. In this work, zinc was used as a doping element for modification. When the doping amount is x = 0.1 (Na0.7Ni0.25Mn0.65Zn0.1O2), it presents enhanced cycle stability in the voltage range of 2.5–4.2 V. The impacts of calcination temperature and cooling methods were investigated. It was found that the material shows excellent stability when the material was calcined at 950 °C followed by natural cooling, the discharge capacity is 64.9 mAh g−1 over 1000 cycles with a capacity retention of 84.0% after 1000 cycles at 170 mA g−1, superior to those reported in literature. In situ XRD reveals a reversible phase transition from P2 to OP4 at the high voltage contributes to the excellent cycle stability. [ABSTRACT FROM AUTHOR] more...

Tin dioxide (SnO2) nanoparticles (NPs) can be applied in several ways due to their low cost, high surface-to-volume ratio, facile synthesis, and chemical stability. There is limited research on the biomedical application of SnO2-based nanostructures. This study aimed to investigate the role of Zn doping in relation to the anticancer potential of SnO2 NPs and to enhance the anticancer potential of SnO2 NPs through Z doping. Pure SnO2 and Zn-doped SnO2 NPs (1% and 5%) were prepared using a modified sol–gel route. XRD, TEM, SEM, EDX, UV-Vis, FTIR, and PL techniques were used to characterize the physicochemical properties of produced NPs. XRD analysis revealed that the crystalline size and phase composition of pure SnO2 increased after the addition of Zn. The spherical shape and homogenous distribution of these NPs were confirmed using TEM and SEM techniques. EDX analysis confirmed the Sn, Zn, and O elements in Zn-SnO2 NPs without impurities. Zn doping decreased the band gap energy of SnO2 NPs. The PL study indicated a reduction in the recombination rate of charges (electrons/holes) in SnO2 NPs after Zn doping. In vitro studies showed that the anticancer efficacy of SnO2 NPs increased with increasing levels of Zn doping in breast cancer MCF-7 cells. Moreover, pure and Zn-doped SnO2 NPs showed good cytocompatibility in HUVECs. This study emphasizes the need for additional investigation into the anticancer properties of Zn-SnO2 nanoparticles in various cancer cell lines and appropriate animal models. [ABSTRACT FROM AUTHOR] more...

Ni-, Zn- and Co-doped Ti/SnO2-Sb anodes were prepared by an unconventional sol-gel method and applied for phenol electrochemical degradation. The longest service life was obtained for Ti/SnO2-Sb-Co (213.9 h), which was longer than Ti/SnO2-Sb-Ni (67.9 h), Ti/SnO2-Sb (2.6 h), and Ti/SnO2-Sb-Zn (0.5 h), and 15 times longer than Ti/SnO2-Sb-Co prepared by conventional thermal decomposition. In addition, Ti/SnO2-Sb-Co showed the lowest energy consumption, which increased in the order Ti/SnO2-Sb-Co < Ti/SnO2-Sb-Ni < Ti/SnO2-Sb < Ti/SnO2-Sb-Zn. Although Ti/SnO2-Sb-Co showed a slightly lower phenol degradation rate (89.2 %) than Ti/SnO2-Sb-Ni (96.7%) and Ti/SnO2-Sb-Zn (92.5%), its longest service life and lowest energy consumption made it the most promising electrode for practical application. The mechanism for increasing service life, decreasing energy consumption and increasing phenol degradation activity was investigated. Co and Ni modification contributes a more compact surface with finer cracks, which is resistant to corrosion and prolongs the service life. The energy consumption is positively related to the charge transfer resistance of electrodes. The increasing phenol degradation activity is due to the high oxygen evolution potential, the high electrochemically active area and the high ratio of Oads/Olat (absorbed oxygen sites/lattice oxygen sites), where the latter two factors contribute more active sites and more · OH formation on the electrode surface. [ABSTRACT FROM AUTHOR] more...

The large structural tolerance of I–III–VI group quantum dots (QDs) to off‐stoichiometry allows their photoluminescence properties to be adjusted via doping, thereby enabling application in different fields. However, the photophysical processes underlying their photoluminescence mechanism remain significantly unknown. In particular, the transition channels of CuInSe2 QDs, which are altered by intrinsic and extrinsic intragap states, remain poorly reported. Herein, we investigated the photophysical processes associated with intragap states via electrochemical and optical techniques by using copper deficient Cu−In−Se QDs as well as Zn doped Cu−In−Se QDs. When the Cu/In molar ratios of Cu−In−Se QDs increased from 0.3 : 1 to 0.9 : 1, the photoluminescence spectra displayed a red‐shift from 700 nm to 1050 nm. Although there was a blue‐shift after the introduction of Zn2+ dopants in Cu−In−Se QDs, a significant red‐shift occurred (from 660 nm to 760 nm) when the Zn/Cu molar ratios decreased from 0.7 : 0.3 to 0.3 : 0.7. The Gaussian deconvolution results of the photoluminescence spectra and the band gap derived from absorption spectra by fitting supported the fact that the optical transition channels are dependent on the Cu/In and Zn/Cu molar ratios. After the introduction of the Zn2+ ions, the alloyed‐resultant blue‐shift of the emission spectra was observed, primarily due to the enlarged band gap; however, the radiative recombination of prominent intrinsic intragap states is still observed; and only a small proportion of the band‐edge exciton undergoes recombination for the sample with low Zn content. Cyclic voltammetry measurements revealed well‐defined extrinsic ZnCu intragap states (Zn substitution on Cu sites) and intrinsic Cux (x= 1+/2+) states in the band gap. The results presented here provide a better understanding of the varying effects of dopant on photoluminescence in terms of I–III–VI group QDs. [ABSTRACT FROM AUTHOR] more...

Polycrystalline NdBaSrCu 3 − x MxO 7 − δ samples (M = Ni or Zn for 0. 0 0 ≤ x ≤ 0. 1 0) were prepared via solid-state reaction and examined by X-ray diffraction (XRD), Scanning electron microscopy (SEM), AC susceptibility and electrical resistance (dc) measurements. This study is focused on the effect of magnetic and non-magnetic particles substitution on the superconductivity of this tetragonal NdBaSrCu3O 7 − δ sample. There is no significant dependence of doping concentration for the changes of a-, b-lattice parameter but c-lattice parameter increased with both Ni and Zn substituted samples contrary to the ionic size considerations of the dopants. Results showed decrease of the critical temperature, T c and critical current density J c (T p) with increase of both doping contents. T p is the peak temperature of the imaginary part of the complex AC susceptibility, χ = χ ′ + i χ ′ ′ . Decrease of T c is related to the disruption of spin correlation of the CuO2 planes. Both doping only affect the T c without changing the transition width. The results showed that both Ni and Zn substitutions alter the quantity of spin-singlet pairs but have no effect on the size of the spin gap in the ladder. However, Zn doping more clearly lowered the T c than Ni doping. It is proposed that Zn, a non-magnetic dopant, caused a greater induction of unpaired charge carriers. [ABSTRACT FROM AUTHOR] more...

Metal halide scintillators have drawn great interest for X‐ray imaging; however, it remains challenging to simultaneously achieve a high light yield (LY) and highly sensitive detection. Herein, Zn2+ is successfully introduced into [TPPen]2MnBr4 (TPPMB, TPPen = pentyltriphenylphosphonium) and the synthesis of [TPPen]2Mn0.9Zn0.1Br4 (TPPMZB) is designed. The LY increases from 43 000 for TPPMB to 68 000 photons MeV−1 for TPPMZB in virtue of the Zn atom doping. Additionally, the detection limit of TPPMZB is 204.1 nGy s−1, showing great improvement to that of TPPMB with the value of 696.9 nGy s−1. X‐ray imaging is realized by utilizing the large‐scale scintillator film fabricated by mixing polydimethylsiloxane with TPPMZB or TPPMB, and the spatial resolution is enlarged from 4.6 to 11.2 lp mm−1 after Zn2+‐doping. This study provides a design principle by doping engineering for enhancing the LY property of metal halide X‐ray scintillators. [ABSTRACT FROM AUTHOR] more...

Perovskite barium titanate (BaTiO3) has received a lot of interest due to its extraordinary dielectric and ferroelectric properties, along with its moderate biocompatibility. Here, we investigated how Zn doping tuned the physicochemical characteristics, photocatalytic activity, and anticancer potential of BaTiO3 nanoparticles synthesized from banana peel extract. XRD, TEM, SEM, EDS, XPS, BET, Raman, and PL were utilized to characterize the as-synthesized pure and Zn (1 and 3 mol%)-doped BaTiO3 nanoparticles. All of the synthesized samples showed evidence of the BaTiO3 tetragonal phase, and the XRD patterns of the Zn-doped BaTiO3 nanoparticles showed the presence of a Zn peak. The particle size of BaTiO3 decreased with increasing levels of Zn doping without morphological changes. After Zn doping, the PL intensity of BaTiO3 decreased, suggesting a lower electron–hole recombination rate. BET analysis found that the surface area of Zn-doped BaTiO3 nanoparticles was higher than that of pure BaTiO3. Under visible irradiation, the photocatalytic activity of pure and Zn-doped BaTiO3 nanoparticles was compared, and a remarkable 85% photocatalytic activity of Zn (3%)-doped BaTiO3 nanoparticles was measured. As a result, Zn-doped BaTiO3 nanoparticles are recognized as excellent photocatalysts for degrading organic pollutants. According to cytotoxicity data, Zn (3%)-doped BaTiO3 nanoparticles display four-fold greater anticancer activity against human lung carcinoma (A549) than pure BaTiO3 nanoparticles. It was also observed that Zn-doped BaTiO3 nanoparticles kill cancer cells by increasing the intracellular level of reactive oxygen species. Furthermore, compared to pure BaTiO3, the Zn-doped BaTiO3 nanostructure showed better cytocompatibility in non-cancerous human lung fibroblasts (IMR90). The Zn-doped BaTiO3 nanoparticles have a reduced particle size, increased surface area, and a lower electron–hole recombination rate, which are highly beneficial for enhanced photocatalytic and anticancer activity. Overall, current data showed that green-fabricated Zn-BaTiO3 nanoparticles have superior photocatalytic and anticancer effects along with improved biocompatibility compared to those of pure BaTiO3. This work underlines the significance of utilizing agricultural waste (e.g., fruit peel) for the fabrication of BaTiO3-based nanostructures, which hold great promise for biomedical and environmental applications. [ABSTRACT FROM AUTHOR] more...

Nb3(Al1–xZnx) (x = 0–0.05) wires were obtained after single rapid heating, quenching and low temperature transformation (single-RHQT) process. It is found that Zn element can make crystal plane diffraction peaks of Nb3Al phase shift to higher angle, and the interplanar crystal spacing decreases gradually, which indicates that Al atoms in Nb3Al lattice are replaced by Zn atoms with smaller diameters. And the addition of Zn can reduce ΔTc and make the superconducting phases purer, and magnetic performances such as critical temperature (Tc), critical current density (Jc), irreversible field (Birr) are better than that of the pure sample. Nb3(Al0.99Zn0.01) wire shows the highest Jc value of about 5.9 × 104 A/cm2 at 4.2 K and 8 T, and the highest Tc value of 16.8 K was found in Nb3(Al0.98Zn0.02). The influence of multiple rapid heating, quenching and low temperature transformation (multi-RHQT) process on Nb3(Al1–xZnx) wires was mainly explored, and 2 at% and 3 at% Zn samples were selected with relatively high ΔTc values for five times RHQT treatment. It is observed that the multi-RHQT process can further reduce ΔTc, and more homogeneous superconducting phases are discovered compared with that of single-RHQT process. The elements are also evenly distributed in the multi-RHQT-processed Nb3(Al1–xZnx) wires, leading to the improvement of Jc, Birr performances compared to single-RHQT samples. Multi-RHQT-processed Nb3(Al0.98Zn0.02) and Nb3(Al0.97Zn0.03) samples show the Jc values of 1.7 × 105 A/cm2 and 1.2 × 105 A/cm2 (4.2 K, 8 T), which are nearly ten times as many as that of single-RHQT samples, and Nb3(Al0.97Zn0.03) has the highest Birr values of 19.6 T (4.2 K) and 10.7 T (10 K). Flux pinning of the Nb3(Al1–xZnx) (x = 0.01–0.05) wires follows the surface pinning mechanism, where grain boundary and stacking faults are considered as pinning centers. [ABSTRACT FROM AUTHOR] more...

As a research hotspot in recent years, Ti-based anode materials for lithium ion batteries (LIBs) have advantages including long cycle life and excellent cyclic stability. However, its application is further limited by its poor conductivity and low reversible capacity. Herein, a series of porous hexagonal prism Zn-doped CoTiO3 have been designed and prepared by simple co-precipitation method followed by calcination. The influences of Zn doping concentration on the microstructure and electrochemical performance are further explored. The results indicate that Zn doping has little effect on the microstructure of CoTiO3 and can elevate capacity, cyclic stability, and rate capability. When Zn doping concentration is set as 0.1, the sample Co0.9Zn0.1TiO3 gives the best electrochemical performance. The reversible capacity can be maintained at 430.6 mAh g−1 at a current rate of 0.2 C after 280 cycles. This work can pave an effective strategy for improving the electrochemical performance of other Ti-based anode materials. [ABSTRACT FROM AUTHOR] more...

Pristine WO3 and Zn-doped WO3 were synthesized using the spray pyrolysis technique to detect ammonia gas. The prominent orientation of the crystallites along the (200) plane was evident from X-ray diffraction (XRD) studies. Scanning Electron Microscope (SEM) morphology indicated well-defined grains upon Zn doping with a smaller grain size of 62 nm for Zn-doped WO3 (Zn: WO3) film. The photoluminescence (PL) emission at different wavelengths was assigned to defects such as oxygen vacancies, interstitial oxygens, localized defects, etc. X-ray Photoelectron spectroscopy (XPS) studies confirmed the formation of oxygen vacancies in the deposited films. The ammonia (NH3) sensing analysis of the deposited films was carried out at an optimum working temperature of 250 °C. The sensor performance of Zn: WO3 was enhanced compared to pristine WO3 at 1 ppm NH3 concentration, elucidating the possibility of the films in sensing applications. [ABSTRACT FROM AUTHOR] more...

In this study, calcium phosphate materials were obtained via a simple, eco-friendly wet synthesis method using hen eggshells as a calcium source. It was shown that Zn ions were successfully incorporated into hydroxyapatite (HA). The obtained ceramic composition depends on the zinc content. When doped with 10 mol % of Zn, in addition to HA and Zn-doped HA, DCPD (dicalcium phosphate dihydrate) appeared and its content increased with the increase in Zn concentration. All doped HA materials exhibited antimicrobial activity against S. aureus and E. coli. Nevertheless, fabricated samples significantly decreased preosteoblast (MC3T3-E1 Subclone 4) viability in vitro, exerting a cytotoxic effect which probably resulted from their high ionic reactivity. [ABSTRACT FROM AUTHOR] more...

Biphasic calcium phosphate (BCP) scaffold has been widely applied to bone regeneration because of its good biocompatibility and bone conduction property. However, the low mechanical strength and the lack of angiogenic and osteogenic induction properties have restricted its application in bone tissue regeneration. In this study, we combined zinc (Zn2+) doping and silk fibroin (SF) coating with expectation to enhance compressive strength, osteogenesis and angiogenesis of BCP scaffolds. The phase composition, morphology, porosity, compressive strength, in vitro degradation and cell behaviors were investigated systematically. Results showed that the scaffold coated with SF exhibited almost 3 times of compressive strength without compromising its porosity compared with the uncoated scaffold. Zn2+ doping and SF coating synergistically enhanced the alkaline phosphatase activity and osteogenesis-related genes expression of mouse bone mesenchymal stem cells (mBMSCs). Furthermore, SF coating notably improved the proliferation, cell viability and in vitro angiogenesis of human umbilical vein endothelial cells (HUVECs). This work provides a novel way to modify BCP scaffolds simultaneously with enhancing mechanical strength and biological properties. [ABSTRACT FROM AUTHOR] more...

Summary: In the development of LiNixCoyMnzO2 (NCM) cathode active materials in lithium‐ion batteries (LIBs) for electric vehicles, it is widely accepted that Ni‐rich and Co‐free NCM is the best candidate for the promotion of electric vehicle deployment. Inspired by the fact that Zn is an element that can be incorporated in regenerated NCM in the LIB recycling, Zn is doped into NCM from an impurity level in the leachate from spent LIBs to a level where Co is completely replaced by Zn. LiNi0.9Co0.05Mn0.05O2 (NCM955), LiNi0.9Co0.0495Mn0.05Zn0.0005O2 (NCMZ‐0.05), LiNi0.9Co0.045Mn0.05Zn0.005O2 (NCMZ‐0.5), and LiNi0.9Mn0.05Zn0.05O2 (NMZ955) are synthesized by a co‐precipitation method. It is confirmed that Zn, which has a similar radius to Li+ and Ni2+, is incorporated into both Li and transition metal layers. An optimum cation mixing on the Zn‐doped NCM surface and the expanded NCM lattice due to Zn doping lead to improved cyclability and rate capability. For example, the optimized NCMZ‐0.5 exhibits enhanced capacity retention of 91.7% compared to NCM955 (69.8%) after 80 cycles. The cyclability improvement of Zn‐doped NCM is ascribed to better reversibility as well as lower overvoltage than NCM955. In particular, NMZ955 displays outstanding capacity retention in cycling tests with a wide voltage range, which implies that Co‐free NMZ has a competitive edge in cyclability compared to NCM. This work not only elucidates the positive effect of Zn doping in regenerated NCM, but also further provides a practical approach to designing a Co‐free Ni‐rich cathode for higher energy density. [ABSTRACT FROM AUTHOR] more...

Vanadium dioxide with monoclinic structure is theoretically a promising layered cathode material for aqueous metal-ion batteries due to its excellent specific capacity. However, its poor cycling stability limits its application as an electrode material. In this study, a series of Zn-doped VO2 (V1−xZnxO2) nanorods were successfully fabricated by the technology of one-step hydrothermal synthesis. The XRD result indicated that there was a slight lattice distortion caused by doped Zn2+ with a larger ion radius. The positron lifetime spectrum showed that there were vacancy cluster defects in all the samples. The electrochemical measurement demonstrated the enhancement of the specific capacitance of V1−xZnxO2 electrodes compared with the undoped sample. In addition, the discharge capacitance of the sample remained around 86% after 1000 charge/discharge cycles. This work proves that Zn2+ doping is a valid tactic for the application of nano-VO2(B) in energy storage electrode materials. [ABSTRACT FROM AUTHOR] more...

In2-xSnxO3-y (ITO) and In2-xZnxSnxO3-y> (Zn0.5-ITO; Zn1-ITO; Zn2-ITO) crystals with the bixbyite structure were prepared by sol–gel spin-coating method, using a densification process at 500 °C to get dense films of 350 nm thickness. For this aim, we report the effect of Zn as doping element of the deposited films on the structural, surface morphology, optical, electrical, and photoelectrochemical properties. The cubic phase with < 100˃-preferential orientation is the same for all samples and Zn doping induces a decreased crystal size. The EDS analysis confirms the presence of In, Sn, Zn, and O elements. The scanning electron and atomic force microscopies (SEM, AFM) show that the films surfaces are continuous and uniform, where most peaks have a pyramidal shape with a compact distribution. The Zn-ITO films exhibit a larger roughness, related to particles agglomeration. The effect of Zn doping on the bands’ shift was observed by UV–Vis spectroscopy and the gap energy decreases with a widened Urbach tail for higher Zn content. The electrical properties are weakly affected and the best conductivity occurs for high-Zn content. The electrochemical stability was demonstrated by the low exchange current density (61 µA cm−2) and large polarization resistance in N2SO4 electrolyte. The interfacial capacitance vs. the potential (C−2–E) indicates n-type conduction. The flat band potential (Efb) and the electron density (ND) have been determined. The large semicircle in the electrochemical impedance spectroscopy (EIS) is attributed to the charge transfer which decreases under UV illumination, supporting the semiconducting character of the films. [ABSTRACT FROM AUTHOR] more...

In the present work, the structural and optical properties of pure and zinc-doped manganese oxide nanoparticles prepared by the sol-gel method have been studied for doping concentrations of 5, 10, and 15 %. The XRD patterns reveal that the cubic phase of pure manganese oxide nanoparticles is changed to tetragonal on doping with Zn. The surface morphology of pure and Zn doped manganese oxide nanoparticles has been studied by Scanning Electron Microscopy (SEM), which reveals appreciable changes in size and shape of the nanoparticles as the doping level of Zn is increased. The optical properties studied by UV-Visible spectroscopy further reveal that the energy band gap increases with a decrease in the size of nanoparticles. [ABSTRACT FROM AUTHOR] more...

In this work, different percentage Zn-doped SnO2 nanoparticles are synthesized by sol–gel process. The crystalline size and band gap of 3 at% Zn-doped SnO2pt> nanoparticle are decreased from 27.4 to 13.6 nm and from 3.37 to 3.28 eV, respectively, deduced by the results of XRD and UV–Vis absorption spectroscopy compared with un-doped SnO2. Zn-doped SnO2 film as a photoanode for dye-sensitized solar cells (DSCs) was characterized and investigated by ultraviolet photoelectron spectroscopy (UPS) and electrochemical impedance spectroscopy (EIS). Conduction band (CB) of the Zn-doped SnO2 is adjusted from − 4.78 to − 4.64 eV via 3 at% Zn concentrations. By adjusting the Zn concentrations, energy offset between the SnO2 and dye is reduced, which accelerates the charge transfer. The cells were estimated once at the interval of one day within 18 days after fabrication. Power conversion efficiency (PCE) of 3 at% Zn-doped SnO2 DSCs increases step by step and achieves 5.18% as the cell is tested after 5 days. This slowly increasing phenomenon of PCE in pure and Zn-doped SnO2 DSCs differs from that of TiO2 and ZnO DSCs. This phenomenon is a different direction for DSCs, revealing the nature of this phenomenon and possibly a breakthrough in efficiency. [ABSTRACT FROM AUTHOR] more...

Proton-conducting solid–oxide fuel cell (H-SOFC) is an alternative promising low-temperature electrochemical cell for renewable energy, but the performance is insufficient because of the low activity of cathode materials at low temperatures. A layered perovskite oxide PrBaFe1.9Zn0.1O5+δ (PBFZ) was synthesized and investigated as a promising cathode material for low-temperature H-SOFC. Here, the partial substitution of Fe by Zn further enhances the electrical conductivity and thermal compatibility of PrBaFe2O5+δ (PBF). The PBFZ exhibits improved conductivity in the air at intermediate temperatures and good chemical compatibility with electrolytes. The oxygen vacancy formed at the PBFZ lattice due to Zn doping enhances proton defects, resulting in an improved performance by extending the catalytic sites to the whole cathode area. A single cell with a Ni-BZCY anode, PBFZ cathode, and BaZr0.7Ce0.2Y0.1O3-δ (BZCY) electrolyte membrane was successfully fabricated and tested at 550–700 °C. The maximum power density and Rp were enhanced to 513 mW·cm−2 and 0.3 Ω·cm2 at 700 °C, respectively, due to Zn doping. [ABSTRACT FROM AUTHOR] more...

The reduced graphene oxide supported Zn-doped Bi2MoO6 nanocomposites (ZnxBi2-xMoO6/RGO) are synthesized by an easy one-step solvothermal method for the rapid degradation of ciprofloxacin (CIP). Characterization analyses show that Bi2MoO6 nanosheets are uniformly supported on RGO, for which the agglomeration of Bi2MoO6 is effectively inhibited, leading to more exposure of surface active sites. The degradation rate of Zn0.1Bi1.9MoO6/RGO5 on CIP reached 90% after 120 min of visible light irradiation, which was 10.4 times the rate of unsupported Bi2MoO6. Zn doping and RGO loading synergistically reduce the recombination rate of photogenerated electron–hole pairs and result in the enhanced photocatalytic performance. Compared with previously reported catalysts, Zn0.1Bi1.9MoO6/RGO5 can get higher degradation efficiency with shorter time and less dosage. In addition, after five cycles, the degradation efficiency is maintained at about 85%, showing perfect cycling stability of Zn0.1Bi1.9MoO6/RGO5. Photocatalytic mechanism suggests that the photogenerated •O2− and h+ are main species for degrading CIP based on ZnxBi2-xMoO6/RGO complex. [ABSTRACT FROM AUTHOR] more...

Development of ultrawide bandgap semiconductor β‐Ga2O3 is important considering its great potential for high‐power high‐voltage electronic applications. Halide vapor‐phase epitaxy is used to produce Zn‐doped β‐Ga2O3 layers on sapphire (0001). Zn doping concentrations is estimated to be in the range between 6 × 1018 and 2.5 × 1020 cm−3. As a precursor for Zn acceptor dopant, ZnCl2 formed by flowing of diluted Cl2 gas over a melt of metallic Zn is used. Modeling of the growth chamber and calculations of precursor concentrations inside the growth zone is carried out to optimize process parameters. The Zn doping is not affecting the optical emission properties; however, growth under oxygen‐rich conditions and formation of crystalline particles on the layer surface are factors responsible for modification of β‐Ga2O3 luminescence spectrum. It is observed that the UV band at 3.35 eV vanishes, whereas relative intensities of the blue and green bands at 2.4–2.8 eV increase. [ABSTRACT FROM AUTHOR] more...

Copyright of Journal of Functional Materials / Gongneng Cailiao is the property of Chongqing Functional Materials Periodical Press and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.) more...

Microstructural control of Nb3Sn wire is quite important for improving the critical current density (Jc). Elemental doping is an effective method to improve the microstructure. In previous work, we have shown that Zn doping of Nb3Sn wire suppresses Kirkendall voids formation, and promotes the Nb3Sn layer formation. As an effective method to dope with Zn, we have previously proposed a Nb/Cu-Ti/Sn-Zn diffusion-pair structural internal tin Nb3Sn wire. In this study, we investigated the effect of Zn doping on the microstructure and the superconducting characteristics of this system, using a single Nb/Cu-Ti/Sn-Zn structural diffusion couple. The Sn composition in the Nb3Sn layer of the Zn doped specimen is slightly slower than that of the non-Zn doped one. The microstructural analysis was carried out by Electron Back Scattered Diffraction (EBSD), Energy Dispersive X-ray Spectroscopy (EDX) and digital image analysis. The average grain size was decreased with Zn doping, leading to an improvement in layer Jc in a low magnetic field. The thickness of the Nb3Sn layer in the Zn doped specimen is also thinner than that in the non-Zn doped one. In the diffusion-pair structure used in this work, increasing of the Zn content in the Sn-Zn core sacrifices the Sn content in the core. A decrease of the Sn content would account for the smaller Nb3Sn thickness in the Zn-doped specimen. [ABSTRACT FROM AUTHOR] more...

It is highly desirable but challenging to develop active and stable electrocatalysts for oxygen evolution reaction (OER) in acid media. Heteroatom incorporation is an effective strategy of defect engineering for optimizing the intrinsic electrocatalytic activities. In this research, zinc‐doped ruthenium oxide (Zn‐doped RuO2) nanorods were prepared by using the facile two‐step method. It is found that the OER activity of Zn‐doped RuO2 catalysts can be readily controlled by varying the amount of Zn dopants. The Zn‐doped RuO2 catalyst with 6.4 at.% displays the best electrocatalytic activity with a low overpotential of 206 mV at 10 mA cm−2, a Tafel slope of 49 mV dec−1 and a long‐term chronopotentiometry test at 10 mA cm−2 for 30 h towards OER in 0.5 M H2SO4 solution. The enhanced OER performance may be attributed to the defective structures caused by Zn doping and the ultrasmall size of the RuO2 nanocrystals. [ABSTRACT FROM AUTHOR] more...

The present work reports a facile strategy to develop L-arginine mediated Zn doped graphitic carbon nitride (g-C3N4) and its enhanced photocatalytic activity. The physicochemical properties of Zn-doped g-C3N4 were studied extensively by XPS, UV–Vis, XRD, SEM and BET analysis. The studied properties of the photocatalyst were then correlated with its photocatalytic hydrogen production rates. Zn doping was evidenced by the presence of Zn-N peak from high-resolution core level XPS spectral analysis. Photocatalytic hydrogen evolution experiments revealed that, upon Zn doping, the hydrogen production rate of g-C3N4 was increased from 34.6 to 78.7 µmol/g.h, i.e. 2.3 times more. The enhancement in the photocatalytic properties after Zn doping was addressed by estimating changes in the positions of conduction band minimum and valence band maximum through XPS valence band spectral analysis. [ABSTRACT FROM AUTHOR] more...

BiFe1−xZnxO3 (x = 0, 0.5, 1, 1.5, 2 mol%) (BFZO) films were prepared on ITO/glass substrates by a sol‐gel method. The effects of different Zn contents on the structures and electrical properties of the BFZO films were investigated. From X‐ray diffraction (XRD), microstructure and X‐ray spectroscopy (XPS) results, the BFZO films with a Zn content of 1 mol% showed a better crystal structure and grain development, and the Fe2+ and oxygen vacancy concentrations in this sample were the lowest among all the evaluated BFZO films. The P‐E hysteresis loop indicated that the BFZO films with 1 mol% Zn had the highest remanent polarization (2Pr), which was 82.4 μC/cm2, along with a coercive field (2Ec) of 887 kV/cm at the tested electric field of 857 kV/cm. The BFZO film with 1 mol% Zn had the lowest leakage current density, which was 3.54 × 10−7 A/cm2 at the tested electric field of 200 kV/cm. Both at high and low electric fields, the space charge‐limited current (SCLC) conduction mechanism was the main leakage mechanism. When the test frequency was 105 Hz, the dielectric constant was 133, and the dissipation factor was 0.015. [ABSTRACT FROM AUTHOR] more...

Attempts have been made to explore the electronic properties and photovoltaic functionality of Zn-doped orthorhombic CH3NH3PbI3 using the generalized gradient approximation method with van der Waals correction (GGA+vdW). Results show that Zn doping effectively decreases the band gap of orthorhombic CH3NH3PbI3, extending the optical absorption into the near-infrared region of solar irradiance. Simultaneously, the incorporation of Zn substantially increases the electron mobility of CH3NH3PbI3, which is expected to assist the dissociation of electron–hole pairs to effectively reduce the probability for their recombination, leading to improved optical absorption. The combined effects of Zn doping on band gap and carrier mobility significantly enhance the photovoltaic functionality of orthorhombic CH3NH3PbI3. The detailed calculation of formation energy for Zn substitution reveals a high favourability to form such doping in orthorhombic CH3NH3PbI3. The outcome of this work offers great promise for widening practical applications of CH3NH3PbI3 for photovoltaic materials or devices. [ABSTRACT FROM AUTHOR] more...

Recently, graphitic carbon nitride (g-C3N4) has been explored as a peroxidase-like catalyst for the nonenzymatic colorimetric detection of H2O2. In this study, we have developed a simple, low cost, and eco-friendly hydrogen bond assisted soft template method of zinc ions doping in mesoporous graphitic-carbon-nitride (Zn-mpg-C3N4) thin nanosheets. Morphology and composition of prepared samples were determined by different characterization techniques. PEG-1500 was beneficial to enhance the porosity and surface area of g- C3N4, whereas zinc loading in the framework of g-C3N4 resulted in the increase in electrical properties. The peroxidase-like catalytic activity of samples was investigated and compared based on the development of blue reaction mixture by the oxidation reaction between 3,3',5,5'-tetramethylbenzidine and hydrogen peroxide (H2O2) through the colorimetric method. The as-prepared 10% Zn-mpg- C3N4 has shown higher peroxidase-like activity as compared to natural HRP, g- C3N4, and mpg- C3N4. This enhanced peroxidase-like activity was attributed to the thin structured nanosheets, higher specific surface area, outstanding electron transfer ability, increased band gap, and increased in charge separation of the catalyst through the direct zinc ions doping modification. The steady-state kinetics mechanism was investigated by using Michaelis-Menten kinetics, and it was found that the reaction followed a ping-pong mechanism. This outstanding catalytic activity permitted us to design a rapid and convenient colorimetric sensing method to detect H2O2. Under the optimized condition, the developed sensor exhibited a linear range of 10- 2000 µM (R ² = 0.9981), limit of detection of 1.4 µM, and limit of quantification of 3.0 µM for H2O2 detection. In view of advantages compared with previous methods such as simple, facile operation, cost-effectiveness, eco-friendliness, naked eye observation, and rapid response, the developed sensor possesses huge potential and is a promising candidate for enzyme mimic sensing of H2O2 in environmental and biological samples. [ABSTRACT FROM AUTHOR] more...

Iron oxide (Fe2O3) nanoparticles were synthesized by a simple co-precipitation method. The effect of Zn concentration on Fe2Oscript>3 nanoparticles was investigated by structural and electronic properties. X-ray diffractograms indicate the formation of a hematite Fe2O3 structure. The calculated particle sizes for undoped-Fe2O3 and Zn-doped Fe2O3 are 31 and 15 nm, respectively. The photocatalytic test was performed against methylene blue to find the efficiency of the photocatalytic activity of the prepared nanoparticles. From the results, it is found that compared to undoped-Fe2O3, the efficiency of Zn-doped Fe2O3 increases considerably. To understand the mechanism behind the photocatalytic activity, a DFT-based calculation was performed to measure the band edge positions of the undoped and Zn-doped Fe2O3 nanostructures and the results are matched well with experimentally observed values. [ABSTRACT FROM AUTHOR] more...

Hierarchical Zn‐doped CoO nanoflowers have been prepared using their hydroxides as precursors. The nanoflowers are assembled by dozens of 2D nanoplates. Each nanoplate is formed by numerous Zn‐doped CoO nanoparticles. Zn‐doped CoO catalyst is highly efficient for electrocatalytic water oxidation with a low overpotential (η=293 mV at j=10 mA cm−2) and long‐term stability, which is comparable to the commercial RuO2 catalysts in alkaline media. The 3D hierarchical structure provides abundant surface catalytic sites, while the density functional theory (DFT) calculations show that the Zn doping is also beneficial for the enhanced oxygen evolution reaction (OER) activities. This series of novel hierarchical porous nanoflowers is a promising anode material for water oxidation. Spring (nano)flowers. The 3D hierarchical structure of the Zn‐doped CoO provides abundant surface catalytic sites and is beneficial for the efficient mass diffusion during catalysis. Zn‐doped CoO catalyst is highly efficient for electrocatalytic water oxidation with a low overpotential (η=293 mV at j=10 mA cm−2) and long‐term stability, which is comparable to the commercial RuO2 catalysts in alkaline media. [ABSTRACT FROM AUTHOR] more...

Single-phase polycrystalline samples of R Ba2Cu2.9Zn0.1O y (R = Y, Nd, Gd, Er, and Tm) (Zn R 123) were synthesized using the standard solid-state reaction method. They were characterized by X-ray powder diffraction (XRD) and scanning electron microscope. XRD shows that all samples consist essentially of a single phase and retain the orthorhombic structure. The structure of the samples was refined by the Rietveld method with the help of the bond valence sum method. The variation of the lattice parameters and some meaningful bond angles and lengths with the ionic radius are discussed. In these compounds, the variations of the buckling angles Cu2–O(2,3)–Cu2 and Cu2–Cu2–O(2,3) are unique: the bond angles Cu2–O3–Cu2 and Cu2–Cu2–O2 increase, whereas the bond angles Cu2–O2–Cu2 and Cu2–Cu2–O3 decrease. The variation of these bond angles brings about a strong curvature of the Cu2O plane. Furthermore, we have found tree fixed triangles formed by the Cu2, O2, and O3 atoms in addition to another fixed triangle O1–Ba–O1 observed for the first time. BVS of Cu2 atom shows a specific and unique variation compared with other compounds. [ABSTRACT FROM AUTHOR] more...

In this research, gas sensing characteristics of undoped and zinc-doped molybdenum trioxide (MoO thin films toward ethanol vapor were investigated. Thin films were deposited using low cost and simple technique of spray pyrolysis on top of glass substrates at 450C. Effects of addition of Zn, as an impurity, on the surface morphology, structural and optical properties of MoO3 thin films were also investigated. X-ray diffraction (XRD) pattern analysis showed that by increasing the amount of impurity, crystal structure changes from orthorhombic -MoO3 to two new phases of monoclinic -ZnMoO4 and Mo5O reduced phase. Field emission scanning electron microscope (FESEM) images showed that by increasing the amount of impurity up to 5at.%, grain sizes decrease to about 60nm. UV-Vis analysis showed that by increasing the percentage of impurity the band gap of thin films increases. Gas sensing properties of samples were studied at three temperatures of 200C, 250C and 300C toward different concentrations of ethanol vapor. Gas response of 5at.% Zn-doped MoO3 thin film reached the maximum value of % when it exposed to 1000ppm of ethanol vapor. Response and recovery times for all samples were reported at different temperatures. [ABSTRACT FROM AUTHOR] more...

Oxide-based thermoelectric materials such as BiCuSeO have been researched for several years to optimize their thermoelectric performance. In this article, we present a series of Zn-doped BiCuSeO ceramics produced by fine processing. The results indicate that Zn doping can effectively increase the power factor through Cu vacancies along with a suppressed thermal conductivity through increased phonon scattering at ZnSe impurity phase. Consequently, a higher ZT value of 0.65 at 873 K is obtained for 10% Zn doping, being about three times larger than that of the pure sample. [ABSTRACT FROM AUTHOR] more...

High-performance thermoelectric BiCuSeO ceramics have been prepared by solid state reaction combined with plasma activated sintering (PAS). Phase compositional and microstructural studies indicate composites having refined grain sizes (600-700 nm) with nanostructured ZnSe secondary phase. Our results reveal that Zn doping can lead to a large change in the carrier concentration (from 0.036 × 1020 cm−3 to 1.50 × 1020 cm−3), thus resulting in an increased electrical conductivity of three orders of magnitude at room temperature. The highest power factor of 4.21 µWcm−1K−2 at 873 K has been achieved by 10% Zn doping. On the other hand, the lattice thermal conductivity has been suppressed significantly due to refined grains, point defects and the nano-inclusions of ZnSe phase. The dimensionless figure of merit ( ZT) could reach up to 0.90 at 873 K in the BiCuSeO oxyselenides by the 10% Zn doping, which makes Zn-doped BiCuSeO to be a promising candidate for thermoelectric applications. [ABSTRACT FROM AUTHOR] more...

We have studied the transport and magnetic properties of the TlKFeZnSe (nominal ratio 0.01≤ x≤0.15) single crystal samples. It is found that although Zn doping leads to a decrease of charge carrier density, it does not affect the superconductivity significantly when x≤0.1. The doped superconductors exhibit properties similar to the parent compound (TlKFeSe), e.g., the almost unchanged superconducting transition temperature ( T) and the 'hump'-like behavior in the resistivity curves, which denotes the transition from insulating phase to metallic phase. As the doping density rises, the hump obviously shifts to low temperature region, implying the quick enlargement of the ratio of insulating phase. The most plausible explanation for the above phenomena is that the Zn impurities prefer entering into the insulating phase only, therefore, merely hindering the formation of superconducting phase without directly changing its properties. The ESR measurement gives low signal-to-noise ratio and just weak paramagnetic signals, revealing strong itinerancy of the Zn doped superconductor. [ABSTRACT FROM AUTHOR] more...

The Zn-doped GdBaCuZnO ( x=0.00-0.40) superconductors have been systemically investigated by structural analysis and positron lifetime. The structural results show that the lattice parameter a and b increase slightly with increasing Zn content x, and the parameter c has a small abrupt decrease. Based on the Jahn-Teller model, we analyze the results of structural distortion. From the positron lifetime data, the local electron density n has been calculated and the result implies a redistribution of electrons between the Cu-O chains and the CuO planes, resulting in the carrier localization. Furthermore, combining the results of the electronic density n and the transition temperature T with Zn doping content, it suggests that the carrier localization could interfere the pairing and the 'charge transfer' between Cu-O chains and the CuO planes and then suppresses superconductivity of the systems. [ABSTRACT FROM AUTHOR] more...

The effect of Zn-doping on the stripe order in LaBaCuO has been studied by means of x-ray and neutron diffraction as well as magnetization measurements. While 1% Zn leads to an increase of the spin stripe order, it unexpectedly causes a wipe out of the visibility of the charge stripe order. A magnetic field of 10 Tesla applied along the c-axis has no reversing effect on the charge order. We compare this observation with the Zn-doping dependence of the crystal structure, superconductivity, and normal state magnetism. [ABSTRACT FROM AUTHOR] more...

In this study, GdBaSr(Cu3−x M x)O7−δ bulk samples ( M=Zn and Ni; 0≤ x≤0.1) were prepared via solid-state reaction. Specific heat measurement (measured with thermal relaxation technique using PPMS) shows an obvious specific heat jump around the T c for GdBaSrCu3O7−δ sample as observed in most of the high temperature superconductors. It shifts towards lower temperature with increasing of both Zn and Ni doping contents, whose tendency is similar to the decreasing of T c. Debye temperature, ΘD (derived from specific heat measurements) calculated at around 10 K is found to be directly proportional to the T c. [ABSTRACT FROM AUTHOR] more...

The critical current density in RABiTS (rolling assisted biaxially textured substrates) based coated conductors is limited by the network of small-angle grain boundaries up to a texture dependent crossover field H∞. The current flow through this network is percolative in nature and thus depends on misorientation angle distribution, the width and length of the tape, and on the grain shape. These dependencies were simulated using a fast and simple limiting path algorithm on real grain boundary networks obtained by electron backscattering diffraction (EBSD) and cross-checked with transport measurements. A strong dependence of Jc on conductor width below 20 grains and a large increase in Jc for elongated grains was found. H∞ of tapes with very sharp cube textures are around 1 T at 77 K. Hence, the intra-grain pinning must be increased for a further improvement of coated conductors applied in higher magnetic fields. With transport measurements on YBa2(Cu1-xZnx)3O7-δ single crystalline thin films, the possibility of a Jc increase due to Zn doping was investigated. Monolayer films with Zn contents up to 0.2%, however, showed a decrease in Jc and Hirr, whereas multilayer films with x = 0.017% and x = 0.025% Zn) showed an increase in Jc at 77 K. [ABSTRACT FROM AUTHOR] more...

Zinc incorporation by post-growth metalorganic vapor phase diffusion (MOVPD) is used to achieve high p-doping, which is desirable for the fabrication of photodiodes. Diethylzinc (DEZ) is used as precursor and Zn is diffused into InP and InAs0.6P epitaxial layers grown by low pressure metalorganic vapor phase epitaxy (MOVPE) on different substrate orientations, enabling the investigation of the dislocation density on the Zn incorporation. Diffusion depths are measured using cleave-and-stain techniques, resistivity measurements, electrochemical profiling, and secondary ion mass spectroscopy. High hole concentrations of, respectively, 1.7 1019 and 6 1018 cm−3, are obtained for, respectively, InAs0.60P and InP. The diffusion coefficients are derived and the Zn diffusion is used for the fabrication of lattice-mismatched planar PIN InAsP/InGaAs photodiodes. [ABSTRACT FROM AUTHOR] more...

Monodispersed CuO octahedral crystals were successfully synthesized using a low-temperature co-precipitation method. Zinc doping in CuO created surface defects that enhanced oxygen adsorption on the surface crucial for gas sensing applications. Pure and Zn-doped CuO sensor films were realized using the doctor blade method. The sensor films showed selective response towards a low concentration of NO2 at a lower operating temperature of 150 °C. Doping with Zn causes the resistance of the sensor film to decrease due to the enhancement of charge carriers with an analogous improvement in the sensor response. The observed decrease in sensor resistance agreed well with the findings of the work function studies. Zinc doping resulted in an increase in work function by 180 meV which, after NO2 exposure, was found to increase by a further 130 meV, attributed to the oxidizing behavior of the test gas. [ABSTRACT FROM AUTHOR] more...

One-dimensional Zn-doped α-Fe2O3 nanowires have been controllably synthesized by using the pure pyrite as the source of Fe element through a two-step synthesis route, including the preparation of Fe source solution by a leaching process and the thermal conversion of the precursor solution into α-Fe2O3 nanowires by the hydrothermal and calcination process. The microstructure, morphology, and surface composition of the obtained products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. It was found that the formation process of α-Fe2O3 is significantly influenced by the introduction of Zn2+. The gas sensing measurements indicated that the sensor based on 1% Zn-doped α-Fe2O3 nanowires showed excellent H2S sensing properties at the optimum operating temperature of 175 °C. Notably, the sensor showed a low H2S detection limit of 50 ppb with a sensor response of 1.5. Such high-performance sensing would be ascribed to the one-dimensional structure and high specific surface area of the prepared 1% Zn-doped α-Fe2O3 nanowires, which can not only provide a large number of surface active sites for the adsorption and reaction of the oxygen and H2S molecules, but also facilitate the diffusion of the gas molecules towards the entire sensing materials. [ABSTRACT FROM AUTHOR] more...

Bacteria existing on the surfaces of various materials can be both a source of infection and an obstacle to the proper functioning of structures. Increased resistance to colonization by microorganisms can be obtained by applying antibacterial coatings. This paper describes the influence of surface wettability and amount of antibacterial additive (Zn) on bacteria settlement on modified SiO2-based coatings. The coatings were made by sol-gel method. The sols were prepared on the basis of tetraethoxysilane (TEOS), modified with methyltrimethoxysilane (MTMS), hexamethyldisilazane (HMDS) and the addition of zinc nitrate or zinc acetate. Roughness and surface wettability tests, as well as study of the chemical structure of the coatings were carried out. The antibacterial properties of the coatings were checked by examining their susceptibility to colonization by Escherichia coli. It was found that the addition of zinc compound reduced the susceptibility to colonization by E. coli, while in the studied range, roughness and hydrophobicity did not affect the level of bacteria adhesion to the coatings. [ABSTRACT FROM AUTHOR] more...