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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]

Realizing visual perception performance using robust metal oxide devices is highly desirable for brain‐inspired neuromorphic computing, visual prosthetics, and artificial intelligence. SnO2, a representative transparent semiconductor, has attracted considerable attention for its potential in ultraviolet photodetectors and photosynaptic devices operating in solar‐blind spectral ranges. This problem has been circumvented by lowering the electron concentration and reducing the persistent photoconductivity (PPC), one of the essential properties of photosynaptic devices. In this case, the electron concentration and PPC properties in SnO2 must be controlled independently. This paper reports the successful control of PPC in SnO2 by controllable addition of Zn and Sr ions, which act as acceptors to annihilate the charge carriers and as a reductant to form oxygen vacancies, respectively. Zn and Sr‐added SnO2 exhibits superior synaptic performance with low energy consumption, successfully imitating the biological synapses without a gate electrode. As a result, the PPC remains at about 40% even after 20 seconds of turning off the ultraviolet light, and energy consumption is reduced to 1–10 fJ, similar to energy consumption with biological synapses. A novel optical sensor that can receive analog signals is demonstrated using a photosynaptic device with Zn and Sr‐added SnO2 thin films. [ABSTRACT FROM AUTHOR]

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]

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]

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]

In this paper, the electronic structure and optical properties of BN doped with different concentrations of Zn (0.062 5, 0. 125, 0. 25) were investigated based on the density functional theory. The results show that the defect formation energies of the three systems after doping are all greater than zero, for this reason the stresses are also calculated which verifies that all of them can exist stably. B1 - x Znx N (x =0, 0. 062 5, 0. 125) is a direct bandgap semiconductor and B0. 75 Zn0. 25 N is an indirect bandgap semiconductor. The bandgap of the system gradually decreases with increasing doping concentration. The doping of Zn leads to the introduction of a receptor energy level near the Fermi level, resulting in the valence band being shifted up above the Fermi level, and the doped systems were all characterized by p-type semiconductor properties. With increasing doping concentration, the static permittivity of the systems gradually increases, the peak of the imaginary part of the doped system gradually decreases, and the value of the corresponding reflectivity at the highest peak gradually becomes smaller. In the low energy region, the doped systems all enhance the absorption of light and the absorption edge red shift. The bond strengths of B--N and N--Zn bonds in the doped systems gradually increase. To sum up, it can be concluded that doping Zn atoms can effectively improve the electronic structure as well as the optical properties of BN. [ABSTRACT FROM AUTHOR]

To manage pathogenic diseases, different applications of nanotechnology have been harnessed to improve the antimicrobial and self-cleaning attributes of materials. The objective of this study is to examine the anti-microbial activity of silk thread; coated (ultra-sonication method) with Zn doped cobalt ferrite nanoparticles with future prospects of developing interlayer of surgical facemask or producing antibacterial wearing. The nanoparticles were synthesized following the co-precipitation method by using Mikania micrantha leaf extract. The potential antibacterial activity (against E. coli and S. aureus) of the thread as well as the nanoparticles was recorded using the Zone of Inhibition (ZOI) test result. XRD results showed the cubic crystal structure and the lattice parameter change due to Zn doping. SEM findings revealed particle agglomeration, though the particles retained an approximately spherical shape of around 52.498 nm for undoped and 32.13 nm for doped materials. FT-IR analysis confirmed that flavonoids from the leaf extract stabilized the nanoparticles. This research investigated the antibacterial capabilities of threads coated with nanoparticles; using the agar well diffusion method, the study established the robust antibacterial capabilities of the nanoparticles-coated thread. Notably, the CoFe2O4 NPs exhibited strong antimicrobial activity against specific bacterial strains, and Zn doping enhances this characteristic.

The study investigated the formation of inhomophase ceramics through Zn doping in Bi 2 СrTa 2 O 9.5–Δ. It was found that all Bi 2 Zn x Cr 1– x Ta 2 O 9.5–Δ (0.3 ≤ x ≤ 0.7) investigated samples crystallized in the pyrochlore structural type (sp. Gr. Fd-3m) and contained an admixture of triclinic β-BiTaO 4 (up to 24 wt %, sp. gr. P-1), with the admixture concentration proportional to the degree of zinc doping. It was shown that impurities in the samples could be eliminated by creating a defective bismuth sublattice proportional to the impurity content, resulting in single-phase Bi 2– y Zn x Cr 1– x Ta 2 O 9.5–Δ (y ≤ 0.5, 0.3 ≤ x ≤ 0.7) samples with the pyrochlore structure. The unit cell parameter of pyrochlore increased with an increase in zinc ion content in the samples from 10.4493 Å (x = 0.3) to 10.4976 Å (x = 0.7). The microstructure of ceramics was represented by individual slightly melted grains 0.5–2 μm in size, which increased in size and fuse with each other with an increase in zinc content. The near edge X-ray absorption fine structure (NEXAFS) and X-ray photoelectron spectroscopy (XPS) data showed that zinc doping did not change the oxidation degree of bismuth and tantalum in pyrochlore, with the ions in charge states Bi(+3), Zn(+2) and Ta(+5). The study also observed an energy shift of the absorption band in the Ta 4f spectrum toward lower energies (Δ E = 0.55 eV) characteristic of tantalum ions with an effective charge (+5–δ) and a shift of the Bi 4f 7/2 and Bi 4f 5/2 bands shift to lower energies with increase in x (Zn), due to the distribution of some Zn(II) ions in the bismuth position. The oxidation degree of chromium ions in the samples was mainly (+3), with some chromium ions oxidized and having an oxidation degree close to (+6) according to NEXAFS data. The studied ceramics showed promise as dielectrics for multilayer ceramic capacitors and devices for microwave applications due to their low sintering temperature and high porosity. [ABSTRACT FROM AUTHOR]

Cu 1.8 S-based materials are regarded as promising thermoelectric materials due to their super ionic nature. The Cu 1.8-x Zn x S (x = 0, 0.01, 0.03, and 0.09) samples were synthesized by the hydrothermal method followed by cold pressing and sintering. The powder X-ray diffraction pattern has confirmed the phase purity and rhombohedral crystal structure of Cu 1.8 S. Additionally, FE-SEM micrographs along with the EDX elemental mapping detected the existence of CuS as the secondary phase in the Cu 1.8 S matrix and uniform distribution of the constituent elements. Upon doping the Zn atom, the Seebeck coefficient subsequently increases owing to the decrement in the carrier concentration, whereas the electrical conductivity gradually reduces. Essentially, the presence of CuS secondary phase and the defects induced by the Zn atom effectively scattered low-mid wavelength phonons, where a very low thermal conductivity of 3.65 W/mK was achieved for Cu 1.71 Zn 0.09 S at room temperature. Ultimately, an overall maximum zT of 0.07 at 573 K was observed for Cu 1.77 Zn 0.03 S, which is about 3.5 times greater than that of the pristine sample. [ABSTRACT FROM AUTHOR]

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]

Oxide nanoparticles (NPs) have attracted considerable interest owing to their unique characteristics and possible applications, including gas detection, bioanalytical sensing, catalytic, and biomedical. The present work was designed to explore the effect of varying amounts (2.5 %, 5 %, and 7.5 mol%) of Zn-doping on the properties and selective anticancer efficacy of In2O3 NPs. The precipitation process was applied to prepare pure In2O3 NPs and Zn-doped In2O3 NPs. XRD, TEM, SEM, EDX, XPS, UV–Vis, and PL techniques have been employed to investigate the physicochemical properties of NPs. The XRD analysis revealed that the crystallite of the In2O3 lattice was slightly changed with the addition of Zn ions. TEM and SEM images displayed that the reduction of size of In2O3 NPs was increased with increasing Zn concentrations. The composition elements and distribution of Zn dopants within In2O3 NPs were further confirmed by EDX and XPS techniques. Based on the UV–Vis study, increasing the Zn amount improved the gap energy of In2O3 NPs by shifting edge absorption peaks to lower wavelengths. Moreover, PL spectra show that the intensity of In2O3 NPs decreased with increasing the Zn amount. The biological results indicate that the Zn-doped In2O3 NPs exhibited a significant increase in cytotoxicity with Zn doping increased against MCF-7 and HCT116cells while they have excellent biocompatibility with normal human cells (HUVECs). These results suggest that these NPs hold promise as a novel therapeutic approach in cancer treatment. This study requires more research into the biological applications of Zn-doped In2O3 NPs.

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]

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]

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]

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]

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]

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]

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]

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]

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]

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]

[Display omitted] In this work, different BiOBr powders (without and with Zn doping) were prepared. Their specific properties and photocatalytic performance were studied. Zn doped BiOBr showed higher carrier transportation ability, beneficial to high performance photocatalysis. Further analysis and theoretical calculations unveiled that Zn doping resulted in more dispersive energy band structure with improved oxygen vacancy (O V) generation due to lattice distortion. O V acted as trap centers, playing dominant role in carrier transportation enhancement, which also synergized with more dispersive energy band due to Zn doping, improving carrier separation and transfer. Besides, Zn doping would further strengthen trapping effect under O V existence, stimulating synergistic enhancement to spatial charge separation and transfer with O V. With synergy of Zn doping and O V , Zn doped samples produced 1.75 times higher CH 4 generation during gas–solid photocatalytic reduction of CO 2 under visible light, testifying successful conducting of Zn doping improved photocatalytic capacity on BiOBr. [ABSTRACT FROM AUTHOR]

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]

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]

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.

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]

The pristine and various mole% (1, 3, 5, 7, and 9) Zn-doped In 2 O 3 nanocrystalline materials have been successfully prepared via the facile sol-gel and screen-printing thick film methods. The crystalline and morphological information for the samples were investigated using various techniques such as XRD, FESEM, HR-TEM, EDAX analysis, and AFM. All the fabricated sensor devices were employed to investigate sensing properties. The resistivity and activation energy properties of all samples were investigated. The 7 % mole Zn doped In 2 O 3 sensor showed superior gas sensing properties and showed excellent selectivity towards NO 2 gas than other doped and pure In 2 O 3 sensors. The sensors were tested at different operating temperatures for NO 2 gas. The highest response of 117 was revealed for 100 ppm NO 2 gas at 50 °C temperature. The optimal sensor device was tested for different NO 2 gas concentrations (50–500 ppm) and long-term stability (90 days). The plausible sensing mechanism was briefed. The Zn doped In 2 O 3 materials could be a potential candidate for highly selective, low-temperature commercial NO 2 sensor device production. [ABSTRACT FROM AUTHOR]

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]

Graphene, g-C 3 N 4 /graphene (NG), CF 2 -modified g-C 3 N 4 /graphene (FNG) films were in situ grown on roving fabric via PECVD, in which Zinc nanoparticles (Zn-NPs) acted as an enhancer integrated by a following chemical method. The nanostructures were revealed by high-resolution TEM, the self-cleaning performance in Zn(NO 3) 2 solution was evaluated, and the interaction model was established with DFT calculation. Results show that the NG@Zn-NPs film presents tightly bound zinc nanoparticles, which are stacked with the NG; whereas the FNG@Zn-NPs film is enriched with the F atoms, which alleviate stacking structure and improves bonding force of Zn-NPs with the FNG surface. The heavy metal ions are efficiently precipitated through the NG@Zn-NPs and FNG@Zn-NPs films. Moreover, the superhydrophobicity of FNG@Zn-NPs film is enhanced by the charge density around the CF 2 functional groups, which further improves self-cleaning performance. • Zn-doped graphene-based films are designed using a plasma process combined with a chemical method. • The nanostructures of integrated Zn nanoparticles in the graphene-based films were revealed by TEM. • Self-cleaning performance was evaluated and the interaction model was established with the DFT calculation. • The micro/nano cell structure and formation of ZnO by the reactive O from the g-C 3 N 4 can improve the self-cleaning ability. [ABSTRACT FROM AUTHOR]

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]

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]

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 SnO2 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]

In this work, we report a sol-gel synthesis-based Zn-doped Na0.6Fe0.5Mn0.5O2 (NFM) cathode and understand the effect of Zn doping on the crystal structure and electrochemical performances such as discharge capacity and rate capability. Detailed X-Ray diffraction (XRD) pattern analysis indicated a decrease in the Na-layer thickness with Zn doping. Small amount of Zn2+ dopant (i.e., 2 at.%) slightly improved cycling stability, reversibility, and rate performances at higher discharge current rates. For example, at 1 C-rate (1 C = 260 mAh/g), the Zn2+-doped cathode retained a stable reversible capacity of 72 mAh/g, which was ~16% greater than that of NFM (62 mAh/g) and showed a minor improvement in the capacity retention of 60% compared to 55% for the pristine NFM after 65 cycles. Slight improvement in the electrochemical performance for the Zn-doped cathode can be attributed to a better structural stability, which prevented the initial phase transition and showed the presence of electrochemical active Fe3+/4+ even after 10 cycles compared to NFM.

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]

WO 3 has been recognized as a promising photoanode for the conversion of solar energy to hydrogen energy through photoelectrochemical water splitting. Herein, Zn-WO 3 nanorod arrays were synthesized by a two-step solvothermal method and then decorated with FeOOH and CoOOH dual co-catalysts layer through electrodeposition. Characterizations confirm the presence of abundant surface oxygen vacancies in Zn-WO 3 , leading to the increase of carriers with high mobility and thus improving the separation (from 63.7% to 92.0%) and injection (from 61.9% to 95.3%) efficiency of carriers. Meanwhile, the dual co-catalysts layer accelerates the transfer of the hole at the interface and inhibits the photocorrosion. Consequently, the optimal 9-Zn-WO 3 -Fe/Co exhibits the photocurrent of 3.63 mA/cm2 at 1.23 V vs. RHE, which is 90.7% of the theoretical value of WO 3 (ca. 4.0 mA/cm2). This work constructs a highly efficient and stable WO 3 photoanode by an integration strategy of transition metal doping and dual co-catalysts modification. [Display omitted] • A facile strategy to prepare Zn-doped WO 3 with dual co-catalysts is developed. • Multiple characterizations confirm the introduction of surface oxygen vacancies. • Effective carrier separation and transfer are achieved through the bulk and surface modification of WO 3. • The photocurrent density of 9-Zn-WO 3 -Fe/Co reaches 90.7% of the theoretical value of WO 3. [ABSTRACT FROM AUTHOR]

Electrochemical water splitting requires new, low-cost cathode electrodes for the hydrogen evolution reaction to enable the worldwide implementation of electrolyzers. Cobalt borides are proposed as one of the most promising materials to overcome the limitations of the commercial electrocatalysts, but the catalytic activity still needs to be improved to be competitive. Here, we report that the introduction of zinc into cobalt boride to produce a ternary cobalt boride is an efficient route to further improve the catalytic activity towards the hydrogen evolution reaction (HER) of cobalt boride. The ternary Co-Zn-B was prepared by an easy chemical reduction method to achieve superior HER electrocatalytic performance with a lower overpotential than the homologous Co-B. The larger surface area, structural order, crystallization degree and, in particular, the different surface chemistry seem to be key factors for this improvement.

Antimony selenide (Sb 2 Se 3 ) has sparked significant interest in high-efficiency photovoltaic applications due to its advantageous material and optoelectronic properties. In recent years, there has been considerable development in this area. Nonetheless, defects and suboptimal [hk0] crystal orientation expressively limit further device efficiency enhancement. This study used Zinc (Zn) to adjust the interfacial energy band and strengthen carrier transport. For the first time, it is discovered that the diffusion of Zn in the cadmium sulfide (CdS) buffer layer can affect the crystalline orientation of the Sb 2 Se 3 thin films in the superstrate structure. The effect of Zn diffusion on the morphology of Sb 2 Se 3 thin films with Cd x Zn 1-x S buffer layer has been investigated in detail. Additionally, Zn doping promotes forming Sb 2 Se 3 thin films with the desired [hk1] orientation, resulting in denser and larger grain sizes which will eventually regulate the defect density. Finally, based on the energy band structure and high-quality Sb 2 Se 3 thin films, this study achieves a champion power conversion efficiency (PCE) of 8.76%, with a V OC of 458 mV, a J SC of 28.13 mA cm -2 , and an FF of 67.85%. Overall, this study explores the growth mechanism of Sb 2 Se 3 thin films, which can lead to further improvements in the efficiency of Sb 2 Se 3 solar cells., (© 2024 Wiley‐VCH GmbH.)

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]