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• A series of four trifluorinated complexes of Eu(III) were synthesized and characterized spectroscopically. • The emission spectra of complexes exhibit hyperintense peak at about 612 nm which is significant for their red emission. • Judd Ofelt parameters provide information about structural and chemical environment around central trivalent ion. • The band gap values show their semiconducting characteristics are responsible for their applications in photonic devices. This article presents the preparation and characterization of a series of four tris-β-diketonate Eu(III) complexes with formulation of [Eu(tfaa) 3 (L) n ], tfaa denotes the 1,1,1-trifluoroacetylacetone, L to monodentate or bidentate neutral ligand with nitrogen and oxygen as donor atom and n can be 1 and 2. The characterization of synthesized complexes was done using infrared spectroscopy, thermo-gravimetric analysis and proton NMR spectroscopy. UV–vis absorption, photoluminescence as well as time-resolved luminescence spectroscopies were also employed to examine the spectroscopic features of ternary complexes. The proton NMR and IR spectral information has suggested the bonding of organic moieties to the Eu(III) ion. The chemical shift obtained for the protons of primary and secondary moieties are shifted in an opposite direction. The band gap values (optical and electronic) suggest the semiconducting nature of prepared europium complexes. The trivalent ion centered emission is shown by all the prepared complexes on excitation under UV-light. The hypersensitive peak situated at about 612 nm responsible for red emission is corresponding to 5D 0 →7F 2 transition and found to be sensitive to the chelating environment present at around emissive ion. Red emanating europium materials have acquired significant utilization in OLEDs, flat panel displays and solid state electronics. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] Laser induced plasma micro-machining (LIPMM) has proved its superiority in micro-machining of hard and brittle materials due to less thermal defects, smaller heat affected zone and larger aspect ratio compared to conventional laser ablation. In order to improve characteristics and stability of induced plasma, this paper proposed magnetically controlled LIPMM (MC-LIPMM) to achieve a good performance of processing single-crystal silicon which is widely used in solid state electronics and infrared optical applications. A comprehensive study on surface integrity and geometrical shape was conducted based on the experimental method. Firstly, the mechanism of MC-LIPMM including laser-plasma, laser-materials interactions and transport effects was theoretically analyzed. Then a series of experiments was conducted to completely investigate the effect of magnetic field intensity, pulse repetition frequency, and bubble behavior on surface integrity and geometrical shape of micro channels. It revealed that magnetic field contributed to maximum reduction of 12.64% for heat affected zone and 62.57% for width while maximum increase of 26.23% for depth and 90.26% for aspect ratio. This research confirms that MC-LIPMM can improve the machining characteristics of silicon materials and cavitation bubbles shows an apparently negative impact on the surface morphology. [ABSTRACT FROM AUTHOR]

The Coulomb blockade effect is commonly used in solid state electronics for the control of electron flow at the single-particle level. Potentially, it allows the creation of single-electron point sources demanded for prospective electron microscopy instruments and other vacuum electronics devices. Here we realize this potential via creation of a stable point electron source composed of a carbon nanowire electrically coupled to a diamond nanotip by a tunnel junction. Using energy spectroscopy analysis, we characterize the electrons liberated from the nanometer scale carbon heterostructures in time and energy domains. Our experimental results demonstrate perfect agreement with theory prediction of Coulomb oscillations of the Fermi level in the nanowire and allow to determine the mechanisms of their suppression. Persistence of the oscillations at room temperature, high intensity field emission with currents up to 1 μA, and other characteristics of our emitters are very promising for practical realization of coherent single-electron guns. Image 1 [ABSTRACT FROM AUTHOR]

Abstract Poly(4-vinyltriphenylamine) (PVTPA) was synthesized, and cross-linked poly(4-vinyltriphenylamine) (PVTPA-CL n) films with a thickness of 260 nm (CL1), 510 nm (CL2), and 680 nm (CL3) were prepared by electropolymerization. Using the PVTPA-CL2 and PVTPA-CL3 films as active materials, the electrochromic devices (ECDs) were fabricated. The structures of the devices were indium tin oxide (ITO) glass/gel electrolyte/PVTPA-CL2/ITO glass (ECD 1) and ITO glass/gel electrolyte/PVTPA-CL3/ITO glass (ECD 2). The electrochromic properties of the PVTPA, PVTPA-CL n films, and ECDs were investigated. Among them, the PVTPA-CL2 and PVTPA-CL3 films exhibited reversible color changes from colorless to gray-green and from colorless to black upon electrochemical doping and dedoping, respectively. The optical contrast of the PVTPA-CL2 and PVTPA-CL3 films were 81.0% and 84.3% at 750 nm, respectively. The ECD 1 could reversibly change between colorless and gray-green under different voltages, and it exhibited 78.3% optical contrast at 750 nm. Notably, ECD 2 could reversibly change between colorless and black under different voltages, and it exhibited 85.0% optical contrast at 750 nm. ECD 1 had shorter switching time than ECD 2, its coloring and bleaching times were 9.5 and 7.3 s, respectively. Both ECD 1 and ECD 2 exhibited reasonable electrochemical cyclic stability. Graphical abstract Image 1 Highlights • PVTPA was synthesized, and cross-linked PVTPA films were prepared by electropolymerization. • The polymer films exhibited reversible color changes upon electrochemical redox. • The PVTPA-CL3 film exhibited reversible color changes from colorless to black. • ECD 2 could reversibly change between colorless and black under different voltages. • ECD 1 and ECD 2 exhibited 78.3% and 85.0% optical contrast at 750 nm, respectively. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • regenerable solution and solid state optical sensors. • sensitivity to metal ions at the ppb level. • selectivity depends on the amount of the probe. • terpyridine as a probe for sensing cadmium. Abstract Six polyfluorene derivatives, P1 – P6 , were synthesized and investigated as responsive materials for the optical sensing of metal ions in an aqueous medium. They were designed by combining carbazole with fluorene units within the backbone. Carbazole was N -functionalized with three coordinating groups, 2-pyridyl-benzimidazole (P1 and P4), 2-phenyl-benzimidazole (P2 and P5) and 4-phenyl-terpyridyl (P3 and P6), respectively. P1 – P3 are random copolymers with fluorene:carbazole ratios of 9:1 for P1 and P2 , and 9.7:0.3 for P3 ; P4 – P6 are the corresponding alternating polymers. This design lead to polymers made of a conjugated backbone and pendant coordinating groups. The optical properties of the monomers were impacted in various ways by metal ions, and the formation of the [Ni M3 ]2+ and [Zn M3 ]2+ and [Zn M3 2 ]2+ were evidenced with association constants of 105.22, 106.45 and 1014.0, respectively. The emission of the polymers was afterwards found to be influenced by theses metal ions with different sensitivity and selectivity. P1 was found to be more sensitive to the Ni2+ and Cu2+ ions with a better selectivity for Ni2+. Emission of the corresponding alternating polymer P4 was more efficiently quenched by these two ions with respect to P1 , in addition of being sensitive to the Ca2+ and Al3+ ions. P3 showed sensitivity to the Ni2+, Cu2+, Al3+, Ca2+, and Zn2+ ions. The luminescence of P6 was much more pronounced with the Ni2+, Cu2+, Cd2+, Zn2+, Al3+, Fe2+, and Fe3+ ions with respect to P3. More remarkably, the presence of the Zn2+ or Cd2+ ions resulted in a new emission band, leading to the possibility to selectively sense these two ions. Relatively high Stern-Volmer constants (in the 106–105 range) were obtained, and sensitivities down to the ppb level were reached, especially for the Ni2+ ion. Influence of both the coordinating group and the polymer backbone on the polymers sensitivity and selectivity was emphasized. Finally, the recyclability of some representative optical sensors was shown both in solution and in the solid state. In particular, thin films were shown to be easily regenerated, which opens the way to the elaboration of reusable optical sensors. [ABSTRACT FROM AUTHOR]

Abstract Cold gas dynamic spray (cold spraying, CS) has emerged as a promising solid state manufacturing technique to fabricate thick metallic deposits with limited risk of oxidation, phase transformations and residual thermal stresses. As-sprayed deposits usually exhibit poor mechanical properties and often require post-spray heat treatments to reduce inter-splat defects. In most of the cases, traditional heat treatments offer limited benefits to rejuvenate the mechanical properties of the deposit. This preliminary work presents an effective way to modify the microstructure and improve the mechanical properties of cold sprayed A380 aluminum alloy. As-sprayed alloy deposits were subjected to hot rolling treatments with different thickness reductions. Results suggest that the hot rolled samples show better strength and ductility compared with their as-sprayed state. Microstructural evolution and resulting mechanical properties, at different processing conditions, were analyzed through optical microscopy (OM), scanning electron microscopy (SEM), electron backscatter diffraction (EBSD), high resolution transmission electron microscopy (HRTEM) and tensile tests. Sample with thickness reduction of 40% displayed highest values of ultimate strength (UTS, 420 ± 2.1 MPa) and elongation (Elf, 5 ± 2.3%) compared with the corresponding values of as-sprayed (100 ± 13.4 MPa, 0%) and conventionally heat treated (186 ± 17 MPa, 0.93 ± 0.05%) samples. The improvement in mechanical properties of the rolled samples were mainly attributed to the progressive elimination/reduction of inter-splat defects together with in-situ composite microstructure formation. EBSD and HRTEM revealed that in-situ composite structure was formed through progressive refinement and uniform distribution of Si particles in α-Al matrix containing coherent θ′ precipitates. Graphical abstract Image 1 Highlights • An effective hot rolling treatment is introduced for cold sprayed A380 alloy deposit. • Hot rolling resulted in efficient healing of splat boundaries & refinement of matrix grains. • With increase in thickness reduction, an in-situ Si/A380 alloy composite is formed. • Hot rolling resulted in significant improvement in mechanical properties of the deposit. [ABSTRACT FROM AUTHOR]

Abstract A series of Ca 8 ZnLa(PO 4) 7 (CZLPO) phosphors doped with Tb3+ and Tb3+, Eu3+ have been synthesized using a high-temperature solid-state method. The XRD pattern verifies that all prepared samples are attributed to whitlockite-type structure of β-Ca 3 (PO 4) 2 with R3c (161) space group. Under 366 nm excitation, the CZLPO: Tb3+, Eu3+ phosphors exhibit a tunable multi-color emission owing to energy transfer from Tb3+ to Eu3+ via a quadrupole-quadrupole interaction mechanism. The emission colors of the phosphors could be modulated from green to red under NUV (366 nm) excitation due to efficient Tb3+→Eu3+ energy transfer. The fluorescence intensity ratio (I 542nm /I 611nm) for the Tb3+→Eu3+ of this material displayed excellent temperature sensing properties between 298 and 498 K. Moreover, it was found that the intensity ratio was unchanged when the temperature was cycled between 298 and 498 K, thus demonstrating the recyclability of this system. These results show that CZLPO: Tb3+, Eu3+ phosphors have potential as high performance multifunctional materials for solid state lighting and temperature sensing applications. Graphical abstract Image 1 Highlights • Whitlockite-type Ca 8 ZnLa(PO 4) 7 :Tb3+, Eu3+ phosphors were designed. • Ca 8 ZnLa(PO 4) 7 :Tb3+, Eu3+ phosphors exhibit a tunable multi-color emission. • The energy transfer mechanism from Tb3+ to Eu3+ were investigated. • Ca 8 ZnLa(PO 4) 7 :Tb3+,Eu3+ phosphors display excellent temperature sensing property from 298 K to 498 K. • This work provides an effective and feasible pathway for the exploration of mmultifunctional applications materials. [ABSTRACT FROM AUTHOR]

Abstract The lead-free Eu3+ doped (Sr x Ba 1- x) 0.98 Eu 0.02 Nb 2 O 6 (SBEN, 0.3 ≤ x ≤ 07) ceramics were fabricated by conventional solid-state reaction method. Eu3+ was chosen as a dopant with the goal of inducing strong red-emitting photoluminescence based on their electrical properties. Effects of Sr/Ba ratio on the crystal structure, dielectric, ferroelectric and photoluminescent properties of SBEN ceramics were investigated by changing x. Single tungsten bronze structure with P 4 bm space group was obtained for all ceramics. The ceramics grain morphology varied obviously from homogenous equiaxed shape to anisometric pillar-type shape with increasing x. According to the dielectric spectra, the obtained SBEN ceramics transited from normal ferroelectrics to relaxor ferroelectrics, accompanied by the gradual decrease of T m with increasing Sr2+ amount in A-sites. Two strong emitting peaks corresponding to the orange magnetic dipole transitions (594 nm, 5D 0 →7F 1) and red electric dipole transitions (618 nm, 5D 0 →7F 2) were obtained for all SBEN ceramics. The red/orange-emitting ratio of Eu3+ related to the Sr/Ba ratio in the composition was studied in this work to discuss the ions occupying situation in different A-sites. Graphical abstract Image 1 Highlights • The photoluminescence is closely linked to the cations occupancy in A sites. • Radius difference between A1 and A2 could contribute to the relaxation behavior. • The 0.07SBEN composition exhibited the best luminescent properties. [ABSTRACT FROM AUTHOR]

Abstract High-temperature thermal storage is essential for advanced solar power and energy saving systems. Cordierite-SiC w (SiC whiskers) composites as candidate sensible thermal storage materials were prepared for high-temperature (above 900 °C) applications by an in-situ synthesis method. The effects of aluminum (Al) on the phase composition and performances of the composites and the growth behaviors of SiC whiskers were studied. XRD analyses results showed that Al addition promoted SiC production whereas lowered cordierite content. The in-situ synthesis of SiC whiskers followed the vapor-solid mechanism rather than the solid-state reaction between silicon and graphite. Al addition was favorable for the production of SiC whiskers with a smooth morphology by increasing the partial pressure of SiO gas. TEM analyses results indicated that the introduced Al changed the growth behavior of the coarse whiskers (>30 nm in diameter) from the self-assembly one to the enlarged nuclei-based one and increased the diameter of the whiskers from 50 nm to 165 nm by enlarging the SiC nuclei. Aluminum could strengthen the composites and enhance the thermal storage capacity by in-situ forming corundum. The high-temperature (900 °C) heat capacity values were improved from 1.28 J g−1 K−1 to 1.4 J g−1 K−1 by introducing 0–20 wt% Al. The lowest thermal expansion coefficient of 3.14 × 10−6 °C−1 (room temperature-1000 °C) was achieved for sample AS1 sintered at 1440 °C due to its highest cordierite content. Graphical abstract Image 1 Highlights • Aluminum(Al) strengthens cordierite-SiC w composites by in-situ forming corundum. • Aluminum can improve the thermal storage capacity of the composites greatly. • Aluminum shows great effect on growth behaviors of SiC whiskers by increasing P SiO. • SiC whiskers with a core-shell structure are synthesized in sample without Al addition. • Aluminum increases the smoothness and diameter of the whiskers by increasing P SiO. [ABSTRACT FROM AUTHOR]

Abstract All-solid-state supercapacitors constructed with effectively composited materials are required urgently for the next generation of portable electronic devices. Herein, two dimensions of materials (carbon nanotubes and exfoliated MoS 2) are used as basic building blocks for deposition of zero-dimensional birnessite-MnO 2 nanoparticles. The obtained ternary hybrids with open conducting nanoarchitecture can provide multiple accessible electroactive sites to minimize the ion-diffusion distances. In a three-electrode aqueous system, the MoS 2 /CNTs-MnO 2 exhibits high specific capacitance (365.6 F/g) and excellent rate capability (76.5% capacity retention at 8 A/g). The advantages of MoS 2 /CNTs-MnO 2 hybrids are evaluated by investigating symmetric and asymmetric supercapacitor using PVDF-HFP/EMIMBF 4 /EMIMTFSI gel electrolyte. The potential window of both symmetric and asymmetric supercapacitor can be enlarged to 4 V. In particular, the asymmetric device provides a maximum energy of 124 Wh/kg at a specific power of 916 kW/kg. It is prospected that such novel hybrids can offer potential promise in energy storage device applications. Graphical abstract Image 1 Highlights • Ternary MoS 2 /CNTs-MnO 2 hybrids with high capacitance were fabricated. • Mixed ionic liquid-polymer gel was used as electrolyte and separator. • The MoS 2 /CNTs-MnO 2 //AC asymmetric device provides an ultrahigh energy density. [ABSTRACT FROM AUTHOR]

Abstract Flexible solid-state supercapacitors show great promise in portable electronics, in which developing advanced electrode materials is a key yet a challenge. This report details an efficient strategy that uses soybean dreg as precursor to purposely prepare nitrogen/oxygen dual-doped porous carbon frameworks by hydrothermal and pyrolysis/activation methods for the first application in flexible solid-state devices. The employed procedure efficiently alleviates the restacking of carbon sheets and well regulates their textural properties and electroactivity to realize outstanding performance. The optimal carbon shows excellent capacitance and rate performance in both three-electrode cell (435 and 336 F g−1 at 0.5 and 50 A g−1) and two-electrode cell (308 and 233 F g−1 at 0.5 and 50 A g−1), which are among the best levels recorded. Significantly, our solid-state supercapacitor achieves integrated high energy and power densities of 9.3 Wh kg−1 and 9883 W kg−1, with a remarkable durability up to 10000 cycles. This device can also work well under various mechanical deformations. For an actual demonstration, two devices are integrated serially, powering a timer for 240 min. This research not only widens the path for designing carbon-based materials, but also brings new idea for device design. Graphical abstract Image 1 Highlights • Hierarchical porous carbon frameworks were derived by sustainable soybean dreg. • Excellent capacitance and rate capability was achieved. • Flexible solid-state supercapacitor assembled showed more practical potential. [ABSTRACT FROM AUTHOR]

Abstract The development of miniaturized and portable electronic devices urgently demands the miniaturization and integration of power sources. Micro-supercapacitors have caught increasing attention in considering their special performance. Herein, we report a type of planar MSC based on the graphene network and nickel hydroxide nanoplates by chemical vapor deposition, mask-free patterning and spray-coating methods. Different interdigital width of graphene network based micro-supercapacitors are researched and the optimized micro-supercapacitor exhibits a high capacitance of 0.34 mF/cm2 at 10 mV/s. Aiming at improving the capacitance and performance of the micro-device, NiOOH/Ni(OH) 2 nanoplates are uniformly deposited on CVD graphene surfaces to obtain all-solid-state graphene/NiOOH/Ni(OH) 2 micro-supercapacitors. This optimal micro-device displays an outstanding capacitance of 0.75 mF/cm2 at 5 mV/s (7.54 F/cm3), a maximum energy density of 1.04 mWh/cm3 and retention of 80% of its original capacity value after 3000 charge-discharge cycles. The enhancement of electrochemical performance of graphene/NiOOH/Ni(OH) 2 micro-supercapacitor is profit by the reversible redox involving two kind of phase transformation of Ni(OH) 2 and NiOOH in both positive and negative. These results demonstrate that our graphene based MSCs provide the potential as self-charging power unit for future integrated electronic applications. Graphical abstract Image 1 Highlights • Graphene and graphene/NiOOH/Ni(OH) 2 composites were the active materials of MSCs. • The optimal GMSC and GNMSC were obtained and analyzed. • The electrochemical mechanism in GNMSC was discussed in detail. [ABSTRACT FROM AUTHOR]

Abstract In this work, blue-emitting aluminophosphate phosphor, Li 2 Sr 2 Al(PO 4) 3 :Eu2+, was prepared by the solid state reaction. The influence of Eu2+ concentration on the excitation and emission characteristics of Li 2 Sr 2 Al(PO 4) 3 :Eu2+ has been studied using optical spectroscopy techniques. Upon near UV-light excitation, Li 2 Sr 2 Al(PO 4) 3 :Eu2+ generates a blue band peaked at 445 nm, and a violet band centered at 398 nm, which originate from Eu2+ ions occupying two kinds of crystallographic sites: Sr(1)O 8 and Sr(2)O 9 , respectively. The luminescence intensities of Eu1 and Eu2 have the strong dependence on the Eu2+ concentration. The contribution of Eu2+ luminescence from Eu1 becomes dominant with high Eu2+-doping. Li 2 Sr 2 Al(PO 4) 3 doped with high level of Eu2+ exhibits a strong narrow-band blue emission with a full width at half-maximum of about 42 nm. Meanwhile, the Eu2+ emission can be efficiently enhanced by codoping with Ce3+ ions using exclusive excitation into the Eu2+ absorption band. The mechanism of luminescence enhancement caused by Ce3+ ions has been determined. These results indicate that Li 2 Sr 2 Al(PO 4) 3 :Eu2+,Ce3+ phosphor might be competitive as a potential blue-emitting phosphor for white LEDs. Graphical abstract Image 1 Highlights • Blue-emitting Li 2 Sr 2 Al(PO 4) 3 :Eu2+,Ce3+ phosphor has been prepared. • Two type of Eu2+luminescent centers are identified in Li 2 Sr 2 Al(PO 4) 3 host. • The sensitization effect of Ce3+ on the Eu2+ emission has been determined. [ABSTRACT FROM AUTHOR]

Abstract The size-dependent electro-thermo-mechanical responses of multilayer cantilever microactuators by Joule heating is investigated. An analytical expression of the deflection of three-layered cantilever microactuators subjected to non-uniform temperature variations and mechanical loading is derived by using the modified couple stress theory and the two-variable method. The predicted result is in good agreement with the experimental data. Compared with the results from the classical beam theory, the influence of the size-dependency on the deformation, equivalent bending rigidity and average thin film stress are discussed. The results reveal that the equivalent bending rigidity of multilayer cantilever microactuators predicted by the present model is larger than that from the classical beam model, which decreases the size-dependent bending response of the microactuator. In addition, the size-dependent average stresses of thin film is more likely to produce mechanical failure. The current study is helpful for the design of micro/nano-actuators. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Ultra-flexible PEDOT:PSS/AgNFs/NOA63 network was fabricated by the peel-off transfer process. • High electro-optical performance with R st of ∼2.12 Ω/sq at 84.7% transmittance was obtained. • The supercapacitor exhibits high areal capacitance (0.91 mF/cm2) with high bending stability. Abstract Energy storage devices that offer high energy storage capacity along with high electro-optical and mechanical performance is still a great challenge as a power source for transparent electronic gadgets. Here, we report the fabrication of an ultra-flexible, lightweight embedded PEDOT:PSS/AgNFs/NOA 63 hybrid transparent supercapacitor electrode (HTSE) film by using a peel-off transfer process technique. The HTSE film shows a good electro-optical performance, the sheet resistance of Rs ∼2.12 Ω/sq at 84.65% transmittance, along with excellent mechanical bending and flexibility characteristics. The HTSE film shows a negligible change in resistance, only a ∼1% increase in resistance is observed after 10,000 bending cycles at a bending radius of 2.0 mm. The HTSE film also exhibits good electrochemical performance with an areal capacitance of 3.64 mF/cm2 at 84.65% transmittance. The fabricated supercapacitor device also exhibits excellent mechanical flexibility, only <1.5% decrease in areal capacitance after 5000 repeated bending cycles at 2.0 mm bending radius. Owing to the high electro-optical, electrochemical and mechanical properties of the HTSE film, the fabricated solid-state supercapacitor device shows high transparency, good electrochemical performance, and long cyclic stability. The HTSE film will be a potential electrode for future transparent portable energy power source, and other flexible transparent electronic devices, an alternative to ITO. [ABSTRACT FROM AUTHOR]

Abstract Organic fluorophores with photoluminescent properties in the solid state are widely applied in modern technology. Of special interest are those molecular materials capable of luminescent "switching" when exposed to external stimuli. However, the development of solid-state molecular systems capable of luminescence tuning over a broad spectral range, especially in the red region, remains a major challenge. In this work an aggregation induced emission phenomenon (AIE) is shown as a favourable strategy for design and development of novel solid-state emitters, especially in combination with excited-state proton transfer reactions (ESIPT). In general, the demanding and complex synthesis of AIE molecular systems (commonly large rotor molecules with luminescence in the blue and green spectral region) is known to be a major drawback of this approach. We present a systematic study of the spectral properties of five AIE- and ESIPT-based solid-state emitters comprising facile synthesis of benzimidazole (BI) derivatives, a new class of candidates for solid–state fluorophores. The five BI-based Schiff bases (compounds 1 – 5) were characterised in solution and solid state using spectroscopic and diffraction methods. All compounds are D-π-A structures with bulky aromatic groups that can undergo twisted molecular conformational change. The presence of the OH group was found to cause excited state intramolecular proton transfer (ESIPT) while different substituents on the π-conjugated backbone allow tuning of solid-state emission from blue to red. The compounds tend to aggregate in water, exhibiting new red-shifted emission bands. Compounds 1 – 5 display very weak emission in solutions, while in solid-state the emission is enhanced to various levels as a result of aggregation induced emission phenomena (AIE). Since AIE can easily be disrupted, the spectral properties of solid-state fluorophores are sensitive to external influence, such as mechanical or chemical stimuli. Reversible mechanochromic luminescence induced by mechanical grinding and subsequent chemical fuming and recrystallisation, is observed for fluorophores 2 – 5 with wavelength shifts of 16 nm, 19 nm, 26 nm and 48 nm, respectively. Fluorophore 5 shows red fluorescence with mechanochromic hysteresis. These results are discussed from a structural point of view and confirm the applicability of the dyes as mechanochromic materials. Graphical abstract Image 1 Highlights • D- π -A molecular systems having multifunctional benzimidazole moiety were derived. • Nanoaggregates in solution exhibit fluorescence emission at higher wavelengths. • Substituents at benzimidazole core allow modulation of solid-state emission. • AIE and ESIPT fluorophore yields red solid-state emission at 625 nm. • External mechanical stimuli exposure allows switching of solid-state emission. [ABSTRACT FROM AUTHOR]

Abstract The historical lead based pigments (XVII-XVIII century), the modern Ni,Sb-rutile (1939) and Pr-zircon (1961) yellow pigments as well as the novel yellow pigments based on Cr-scheelite and Mo-yttrium cerate pigments were synthesized and compared as semiconductors of high NIR reflectance (cool pigments) and with photocatalytic activity. All powders are wide band gap semiconductors (E g =2.1–3.1 eV) with high NIR reflectance, ranging from 80% for Cr-Scheelite to 86% of Naples yellow, except Ni,Sb-rutile pigment that shows 55%. The low color performance of lead based pigments in alkyd paint and lead-free glazes along with its toxicity, discard these pigments as cool eco-friendly pigments. The Pr-zircon, Cr-scheelite and Mo-yttrium cerate pigments exhibit high NIR reflectance (R NIR = 80–83%) and yellow coloration (b* = 57.6–45.3) but only Pr-zircon and Cr-scheelite show color stability in alkyd paint and lead free glaze applications. Regarding to results of Orange II photodegradation test, lead based and Ni,Sb-rutile pigments inhibits the photolysis of the UV irradiation, acting as protecting agents from irradiation. The Mo-cerate shows a slight photocatalytic activity (t 1/2 = 301 min) and both Cr-scheelite and Pr-zircon pigments show a moderate activity (t 1/2 = 198 and 184 min respectively). Looking at a possible industrial application, the leaching test shows that the fluorides released by Pr-zircon (16.8 mg/g) as well as the Cr(VI) of Cr-scheelite (6 mg/g) should be treated and controlled. The Cr-scheelite solid solution Ca(Cr x W 1-x)O 4 is stable to x = 0.2 but its pigmenting capacity saturates at x = 0.1. [ABSTRACT FROM AUTHOR]

Abstract Although extensive studies have been carried out on n-type semiconductors for room-temperature gas sensor applications, some intrinsic problems remain. Therefore, other interesting attempts should be adopted to solve these issues, like p-type semiconductors. Previous studies have demonstrated that p-type semiconductor gas sensors exhibit better selectivity and less humidity dependence due to the distinctive oxygen adsorption and surface reactivity. Visible light is used as the external activation source to accelerate the sensing kinetics instead of heating. Stoichiometric NiO cannot absorb visible lights. Inspired by the works of black TiO 2 , we adopted three methods to prepare black NiO. XPS characterizations reveal that the presence of Ni3+ ions leads to the formation of black NiO. However, not all black NiO samples show good responses to NO 2 at room temperature. Three main routes: synthesizing specific morphology with large specific surface area and porosity, introduction of Ni3+ ions and oxygen vacancies, are needed to get the enhanced sensing performance. The black NiO samples with large specific surface area and oxygen vacancies and Ni3+ ions show obvious response towards ppb-level NO 2 with visible light irradiation at room temperature. Furthermore, light wavelength is found to play a vital role in the sensing characteristics, and blue light is the optimal choice. Different from traditional NiO sensors operated at high temperatures exhibiting superior response to reducing gases, the black NiO show excellent selectivity towards oxidizing gas, ppb-level NO 2 , at room temperature illuminated by blue light. In contrast with n-type semiconductors, the black NiO samples also exhibit less humidity dependence. Highlights • Black NiO samples were synthesized by three different routes by introducing Ni3+ ions. • The light absorption range of black NiO was extended to the whole visible light region. • Three main factors enhance the sensing performance of black NiO. • Visible-light-assisted black NiO shows excellent response to NO 2 at room temperature. • Light wavelength plays a crucial role in sensing performance and blue light is optimal. [ABSTRACT FROM AUTHOR]

Abstract This article describes how the increased use of energy-efficient solid-state light sources (e.g., light-emitting diode [LED]-based illumination) in hospitals, pharmacies, and at home can help alleviate concerns of photodegradation for pharmaceuticals. LED light sources, unlike fluorescent ones, do not have spurious spectral contributions <400 nm. Because photostability is primarily evaluated in the International Council of Harmonization Q1B tests with older fluorescent bulb standards (International Organization for Standardization 10977), the amount of photodegradation observed can over-predict what happens in reality, as products are increasingly being stored and used in environments fitted with LED bulbs. Because photodegradation is premised on light absorption by a compound of interest (or a photosensitizer), one can use the overlap between the spectral distribution of a light source and the absorption spectra of a given compound to estimate if photodegradation is a possibility. Based on the absorption spectra of a sample of 150 pharmaceutical compounds in development, only 15% would meet the required overlap to be a candidate to undergo direct photodegradation in the presence of LED lights, against a baseline of 55% of compounds that would, when considering regular fluorescent lights. Biological drug products such as peptides and monoclonal antibodies are also expected to benefit from the use of more efficient solid-state lighting. [ABSTRACT FROM AUTHOR]

Abstract This paper reports the structural, morphological and thermoluminescent studies of Eu2+ and Er3+ ions activated ASiO 3 (A = Ca, Ba, Sr) phosphors synthesized via conventional solid state reaction method. The impurity ions concentration of both Eu2+ and Er3+ ions varies from 0 mol% to 1 mol%. The study of crystallographic traits of the synthesized phosphors is done by Powder X-Ray Diffraction (PXRD) analysis. The crystalline nature, phase purity and appreciable homogeneity of the synthesized phosphors were confirmed by this study. The distinct morphological and topographical features were studied through Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). The thermoluminescent (TL) behavior of ultraviolet (UV) irradiated and gamma irradiated ASiO 3 :Eu2+, Er3+ (A = Ca, Ba, Sr) phosphors were studied here and the various kinetic parameters were estimated by Computerised glow curve deconvolution (CGCD) technique and peak shape method. The UV and gamma irradiated phosphors exhibit second order kinetics. The high values of activation energy (∼3 eV) confirm the trapping of electrons in deep trap centers. The incorporation of doping ions into the host lattice causes non-valence substitutions at the substitutional sites. This increases the number of defects and vacancies in the phosphors and more trap centers were generated. The increased TL intensity and high temperature glow peaks confirm the same. The synthesized phosphors show enhanced TL characteristics, efficient trapping mechanism and low fading effects. These characteristics confirm the suitability of the synthesized phosphors for TL mapping and sensing applications. Highlights • ASiO 3 :Eu2+,Er3+ (A = Ca,Ba,Sr) phosphors exhibit enhanced TL intensity and low fading characteristics. • The γ-irradiated phosphors were found more suitable due to efficient trapping mechanism. • The synthesized phosphors were competent for radiation sensing and mapping applications. [ABSTRACT FROM AUTHOR]

Abstract A time-of-flight elastic recoil detection analysis measurement system has been developed for analyzing the light elements in thin films. The system consists of two time detectors and a silicon detector, and the energy and time-of-flight of recoil ions are measured simultaneously. This system has been tested using He, C, and Cu beams with energies between 2 and 20 MeV. Depth resolutions at the surface of a thin carbon layer were 1.3 ± 0.1 nm with a 2-MeV 4He beam and 1.6 ± 0.2 nm with a 5-MeV 63Cu beam. The sensitivity of oxygen measurements was evaluated to be 3.8 × 1014 cm−2 when using a 12-MeV 63Cu beam. [ABSTRACT FROM AUTHOR]

Abstract ZnS x Te 1-x thin films were prepared by sulfur implantation into ZnTe grown by molecular beam epitaxy and subsequent pulsed laser melting. The chemical composition and layer thickness of the ZnS x Te 1-x layer have been analyzed based on Rutherford backscattering spectrometry. Raman and photoluminescence spectroscopies were employed to reveal the optical properties of the ZnS x Te 1-x layer. Raman spectra exhibit a redshift of the longitudinal optical photon modes with increasing sulfur concentration. The room temperature photoluminescence measurement indicates the appearance of the sulfur induced energy state in the bandgap. [ABSTRACT FROM AUTHOR]

Abstract The crystal structure, microstructure, and magnetic properties of Bi 0.84 La 0.16 Fe 1-x Ti x O 3 (x = 0.1, 0.14, 0.16, 0.2) ceramic samples prepared by solid-state reaction are investigated by combining X-ray diffraction, Raman scattering, scanning electron microscope, and magnetic measurements. The analysis of crystal structure reveals the presence of multiphase structures and the gradual formation of Aurivillus Bi 5 FeTi 3 O 15 phase when increasing Ti concentration. The microstructure study shows several grain shapes, corresponding to the different crystal structures and phases present in the sample. The competition in lattice strain of the coexisting phases leads to the isothermal structural transition and the self-change in magnetization. A drastic decrease in coercivity and an increase in magnetization are observed with increasing ferromagnetic-like hysteresis loops. The change in magnetic properties of the samples is strongly dependent on the coexisting phases in the samples. [ABSTRACT FROM AUTHOR]

Abstract Manufacturing materials for high performance applications with tailored properties requires a deep knowledge about the sintering process and especially the underlying microstructure evolution. Due to the complex interplay of the material and process parameters as well as complex geometries it is challenging to predict the microstructure evolution during sintering with analytical models. A phase-field model based on the grand potential approach considering volume, surface and grain boundary diffusion is presented to describe the microstructural evolution during solid state sintering. To efficiently investigate realistic green bodies with multiple thousand particles in three dimensions, the model is implemented in a highly optimized manner in the massive parallel phase-field solver framework Pace3D. By comparing the neck growth rates and the particle approach in a two particle system for the different diffusion mechanisms a good agreement to analytic solutions is found. Based on a three dimensional green body of 24897 Al 2 O 3 -grains the densification is investigated with respect to the dominant diffusion mechanisms and compared with the analytic Coble model. Finally, the appearance of isolated pores in the microstructure is discussed. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract Phases in the Cu-Zn-Sn-S system are of interest to the solar and thermoelectrics communities because all elements are earth-abundant and non-toxic. A better understanding of the structures of these phases and the equilibria between them is necessary to guide device manufacturers. This work reviews all the phases reported in this system and reports which phases form and are stable at 200 °C and 400 °C. In this work, the stable phases in the Cu-Zn-Sn-S system ( Cu 4 Sn 7 S 16 , Cu 4 SnS 4 , Cu 2 ZnSnS 4 , and Cu 2 SnS 3 ) are synthesized and their structures are investigated using solid-state NMR, X-ray diffraction, and Raman spectroscopy. The existing Cu-Sn-S and Cu-Zn-Sn-S phase diagrams are revised based on our synthesis results. Cu 3 SnS 4 and Cu 2 ZnSn 3 S 8 are removed from the quaternary and ternary phase diagrams because we did not observe either phase. Prior reports (in thin films and nanocrystals) of Cu 3 SnS 4 may be related to trace amounts of In or large surface areas. Monoclinic Cu 2 SnS 3 is not stable at 400 °C and, at this temperature, a disordered tetragonal phase is stable. At lower temperatures (room-temperature and 200 °C), this same (disordered) tetragonal phase is stable at compositions that are Cu-rich and Sn-poor from Cu 2 SnS 3 . Cu 4 SnS 6 was added to the phase diagram at 400 °C. Significant differences in reaction rate when forming Cu 4 SnS 4 from either elemental or binary sulfide precursors are noted and explained. The NMR results are generalized to aid in distinguishing octahedral versus tetrahedral Sn4+ coordinations. Graphical abstract fx1 Highlights • Ss-NMR: useful for studying Sn 4 + coordination and Cu-Zn-Sn-S system structures. • Cu-Zn-Sn-S and Cu-Sn-S phase diagrams at room-temperature, 200 °C, and 400 °C. • Cu 3 SnS 4 reports may be due to indium contamination. • Kinetic barriers to Cu 4 SnS 4 from elemental precursors but not binary precursors. • Order-disorder transitions between 200 °C and 400 °C in Cu 2 SnS 3 and Cu 2 ZnSnS 4 . [ABSTRACT FROM AUTHOR]

Abstract This paper focuses on the development of a predictive cycle life model of all-solid-state thin film Cu/Li/LiPON/LiCoO 2 microbatteries based on experimental accelerated aging tests. More than 120 samples were tested in 8 different conditions including several electrochemical cycling modes and different temperature levels. Hence, an original reliability model, based on an exponential function especially designed to describe the degradation mechanism occurring at the positive electrode, is proposed to describe the observed capacity loss evolution of microbatteries. An extended mathematical model, which includes a large set of accelerated factors, physicochemical considerations and statistical parameters is then built around such an exponential function. This model thus enables to simulate a wide variety of battery aging profiles from input parameters such as temperature, depth of charge (DoC), discharge rate, failure rate and capacity fade. We believe that the development of such a reliability model is of most importance not only from an industrial point of view, since it enables to determine precisely the expected behavior of microbatteries in various mission profile conditions, but it represents also a key tool that enables to further understand the observed degradation mechanisms, and to identify any technological optimization opportunities. Highlights • Evaluation of intrinsic reliability performances of solid-state microbatteries • Introduction of an exponential function to fit aging data from a reliability study • The predictive model enables to simulate a wide variety of battery aging profiles. • Possibility to consider a statistical dimension [ABSTRACT FROM AUTHOR]

Abstract Aurivillius Bi 4 NdTi 3 (Fe 0.5 M 0.5)O 15 (M-BNTF, M = Cr, Ni, Fe, Co, Mn) thin films were prepared by a sol-gel method. Single-phase four-layered perovskite structure of all the M-BNTF thin films was characterized by X-ray diffraction and FT-IR spectra. Typical plate-like grains with different grain sizes were observed in the M-BNTF thin films. Optical properties were measured by a UV–vis spectrometer, and all the films have direct bandgaps. The bandgaps of the Cr-, Ni-, Fe-, Co- and Mn-BNTF films were calculated to be about 3.45, 2.84, 2.58, 2.47 and 2.37 eV respectively through the Tauc's power law. The bandgap tuning is attributed to the cationic disorder and the large distortion of MO 6 octahedron by the M ions doping which was verified by the calculation of lattice parameters and Raman measurements. The present work may help shed light on the origin of the bandgap tunability for bismuth-contained Aurivillius ferroelectric compounds and promote them to get more extensively application in the new photovoltaic cells and other novel optoelectronic devices. Highlights • The effect of Fe-site M-doping on the structure and E g of BNTF were investigated. • M-doping doesn't change the crystal structure but alters growth kinetic behaviors. • The E g decreases in the order of Cr-, Ni-, Fe-, Co- and Mn-BNTF thin films. • The variation range of the E g is 1.08 eV. • The tuning of E g was attributed to the cationic disorder and the distortion of MO 6. [ABSTRACT FROM AUTHOR]

Abstract Photoelectric conversion efficiency of organic-inorganic perovskite solar cells has been rapidly raised and attracted great attention in recent years. The quality of perovskite films is vital for the performance of devices. We used the anti-solvent method to prepare CH 3 NH 3 PbI 3 thin films by spin coating and dried them at various temperature to transform adduct MAI·PbI 2 ·DMSO into CH 3 NH 3 PbI 3. We researched in detail on the relationship between surface morphology of MAPbI3 thin films fabricated by the anti-solvent method and various drying temperature. We found that surface roughness and grain size of CH 3 NH 3 PbI 3 films together increased with increasing drying temperature. The larger grain size could efficiently reduce crystal boundaries which is advantageous for the suppression of photo-induced charge carrier recombination resulting in increase of FF. However, increase of surface roughness resulted in larger contact area at interface which might produce more tarp states and poorer wettability of HTM solution leading in decrease of J sc. Surface morphology of MAPbI3 layer on the performance of solar cell devices is also an important research issue. By optimizing the drying temperature to 60 °C, the highest efficiency of 14.4% was achieved for the CH 3 NH 3 PbI 3 -based solar cell devices. Highlights • CH 3 NH 3 PbI 3 surface roughness influences the wettability of HTM solution. • Interface area and defects should be increased and decreased, respectively. • Drying temperature of CH 3 NH 3 PbI 3 solution film was optimized to 60 °C. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Sb-doped SnO 2 thin films have been deposited by the dip-coating technique. The morphology analysis revealed that the surface is granular, crack-free and the average roughness varies with Sb-doping. The sub–band gap electronic transitions were successfully probed using the optical and Mott-Schottky measurements. Therefore, the energetic band diagrams were established to locate the conduction band (3.85 eV) and valence band (7.69 eV) below vacuum. The concentrations of shallow and deep donors were determined from the pseudo-slopes. The charge transport was achieved with bulk-localized states which mediate the carriers tunneling. The electrical conductivity above 1 V, involves electrons hopping between tail states and the current increases exponentially (I ∼ e a. V). The ac-conductivity is enhanced with increasing the thermal energy, which promotes the carriers hopping. The photoconductivity revealed that the tunneling mechanism is sensitive to the localized states overlapping, thus generating donor and/or traps levels within the forbidden band. [ABSTRACT FROM AUTHOR]

Abstract Solid-state ion exchange with an applied voltage enables metal doping of alkali-silicate glass surfaces. When the silver is used as the doping agent, application of a reverse voltage produces a silver layer buried in the glass substrate. The silver layer consists of a network of silver nanowires that have high electrical conductivity. In this work, we experimented with forming fine electrical paths in a glass substrate using silver nano-ink, an organic solvent containing dispersed silver nanoparticles printed on the glass surface, as the silver ion source. As a result, silver precipitation line of fine width/pitch (89/16.8 μm on average) were formed by sequentially applying forward and reverse voltages. We carried out a two-dimensional numerical analysis of the ionic diffusion behavior under an electric field to calculate the minimum line interval that would prevent two adjacent lines from overlapping. In this method, the buried silver layer is, in principle, connected to the glass surface via some precipitations, and we found an arrangement for the cathodes that confines the connection paths to the designed areas. Highlights • We proposed a formation method of fine electrical paths in a glass substrate by electrical field-assisted solid-state ion exchange. • Fine silver precipitation lines (width/pitch: 89/16.8 μm) were formed by sequential application of forward and reverse voltages. • Two-dimensional numerical analysis of the ionic diffusion behavior was conducted to prevent the overlapping of two adjacent paths. [ABSTRACT FROM AUTHOR]

Abstract Crystalline organic light-emitting diodes (OLEDs) are of great potential for the applications in solid-state lighting and electrically pumped organic lasers. Now the performance of crystalline OLEDs is poor because those devices typically use a single organic material with unmatched electron and hole mobilities resulting in imbalance charge injection. Here, we fabricate a crystalline OLED with a multi-layer architecture based on high-quality crystalline films. The device exhibits low driving voltage and high efficiency due to balanced charge injection and exciton confinement. An external quantum efficiency (EQE) of 2.41% is achieved, and the EQE value is the highest efficiency in the field of crystalline OLEDs to date. We expect that our results will be a starting point for further research, providing high-performance crystalline OLEDs for solid-state lighting and electrically pumped organic lasers. Graphical abstract Image 1 Highlights • High-quality multi-layer crystalline films were prepared. • The multi-layer crystalline OLED features balanced charge injection and exciton limitation. • The multi-layer crystalline OLED exhibits low driving voltage and high efficiency. [ABSTRACT FROM AUTHOR]

The power distribution system is evolving towards a smart grid paradigm facilitated by infrastructure improvement, innovative technologies, and electronically-interfaced devices. The solid state transformer (SST) promises to be one of the most significant power electronically-interfaced devices to be integrated in the next generation distribution network due to its extensive energy management capability to handle interconnected AC and DC source(s) and load(s). In this paper, a three-phase unbalanced Optimal Power Flow (OPF) algorithm is extended for integrating distributed energy resources (DER) and SSTs in the future distribution networks. The purpose of the OPF is to optimize the economic operations of DERs in conjunction with the SST to improve system efficiency and voltage profiles, while controlling DER penetration. The topology and functionalities of the SST are introduced and modeled in the OPF algorithm. Comprehensive models of loads, conductors, voltage regulators, transformers, and pricing schemes are considered for accuracy. Based on the theoretical foundations, simulations are conducted on the IEEE 123 bus test system. The entire algorithm is also visualized in a quasi-static time-series (QSTS) manner to capture the variability of the system and response of the SSTs in different control modes. This can be adopted by distribution automation enterprises for active distribution networks. [ABSTRACT FROM AUTHOR]

Abstract The Na+/Li+ substitution in Na 3 V 2 (PO 4) 2 F 3 is studied using different synthesis approaches: equilibrium and non-equilibrium. In the equilibrium solid-state process, the reagent mixtures with various Na/Li ratios are preliminary mechanically activated using a high-energy AGO-2 planetary mill and then annealed in an Ar flow. Non-equilibrium chemical Na/Li ion exchange is performed in the organic solution of LiBr as a Li source. Phase composition, crystal structure, morphology and electrochemical properties of the as-prepared materials are analysed by XRD, SEM, TEM, EIS, galvanostatic cycling, and cyclic voltammetry. It is shown that the solid-state synthesis leads to the lower substitution degree and is accompanied by the formation of the V 2 O 3 impurity. These samples are characterized by enhanced electrical conductivity (by about 4 orders of magnitude) compared to that of the pristine Na 3 V 2 (PO 4) 2 F 3 , and improved high-rate performance both in Na and Li-cells. The origin of the excellent high-rate capability of the as-prepared Na 3-x Li x V 2 (PO 4) 2 F 3 is partially attributed to the pseudocapacitive effect initiated from the rational design of the materials, including submicron particles, mixed in-situ coating with electron-conductive carbon and V 2 O 3. Graphical abstract Image 1 Highlights • Na 3-x Li x V 2 (PO 4) 2 F 3 were prepared by the solid-state and ion exchange approaches. • Na 3-x Li x V 2 (PO 4) 2 F 3 solid solutions preserve the crystal structure of Na 3 V 2 (PO 4) 2 F 3. • Solid-state synthesis of Na/Li compositions is accompanied by in situ V 2 O 3 formation. • V 2 O 3 significantly enhances electronic conductivity and high-rate performance. • High-rate capability was partially attributed to the pseudocapacitive effect. [ABSTRACT FROM AUTHOR]

Thermal response of thin films under pulse heating, resembling laser pulses, is considered and the semi-analytical solution of phonon radiative transport is presented. Temperature pulsation is introduced at the film edge resembling the laser pulses and silicon thin film is used as the film material. Since the film thickness is comparable to the mean free path of silicon, equation for radiative phonon transport is incorporated in the analysis. Temperature findings from the semi-analytical solution are compared to that obtained from the numerical solution. Equivalent equilibrium temperature is introduced to quantify the phonon intensity distribution in the film. It is found that equivalent equilibrium temperature obtained from the semi-analytical solution agrees well with its counterpart obtained from the numerical simulations. The semi-analytical solution correctly predicts the temperature jump at the film edges. The semi-analytical solution reduces the computation efforts significantly in terms of run time and memory size, which are required for the numerical simulations. Temporal distribution of temperature inside the film at various locations does not follow exactly the temperature pulses introduced at one edge of the silicon film. [ABSTRACT FROM AUTHOR]

Well-aligned parallel nanoripples, with spacing down to 250 nm, were engraved on a glass surface at a fluence 8 times less than the ablation threshold of glass using IR (λ = 1032 nm) picosecond laser system with a pulse duration of 10 ps. The glass surface was first coated with 175 nm ITO thin film prior to laser scanning. The nano-ripples were formed on the underlying glass surface during the selective removal of ITO thin film using substantially less fluence than that required without ITO on the glass surface. The laser scan speed and repetition rate determine the spatial overlapping of pulses (shots per area, SPA); this greatly influences the symmetry, spacing, and depth of the ripples achieved. The fluence ranging from 1.13 to 1.56 J cm −2 at scanning speed of 0.5 ms −1 , 25 SPA, 96% overlapping at laser repetition of 400 kHz was found to be the optimal laser parameters for generating nano-ripples with 0.25λ periodicity on large area glass surface. The process offers the opportunity for gratings to be integrated in structures consisting of transparent conductive materials. [ABSTRACT FROM AUTHOR]

In this study, nonlinear and saturable absorption behaviors of nanocomposite TiO 2 /carbon based materials in PMMA were investigated. Transparent thin films of TiO 2 , HC/TiO 2 , CNT/TiO 2 , CNT/TiO 2 -Pt nanocomposites were synthesized by spin coating. Linear absorption measurements indicate blueshift in energy due to a quantum confinement effect. Nonlinear optical absorption characteristics of the composite films were investigated using open aperture Z-scan technique with at the same fluence values for nanosecond and femtosecond pulse durations. To derive the transmission in open aperture Z-scan data, a theoretical model incorporating one photon, two photon, and free carrier absorptions and their saturations were considered. Nonlinear absorption coefficients and saturation intensity thresholds were extracted from the fitting of the experimental results for both pulse durations used for the experiments. Saturation intensity threshold values in femtosecond regime are significantly bigger than the values in nanosecond regime while nonlinear absorption coefficients values in nanosecond regime are significantly bigger than the values in femtosecond regime. These behaviors are attributed to localized defect states in the energy gap due to the loss of long-range order and defects such as dangling bonds and impurities. With thermal annealing processes at 200 °C and 450 °C nonlinear absorption coefficients and saturation intensity thresholds decrease due to reduction of localized defect states. [ABSTRACT FROM AUTHOR]

Highlights • High resolution analysis of the Dyad and Pentad of 73GeH 4. • Resonance interactions in spherical top molecules. • Determination of spectroscopic parameters. • Line list of 9208 transitions. Abstract The spectra of germane enriched up to 99.9 % of 73GeH 4 were recorded with a high resolution (0.003 cm − 1) at different pressures with the Bruker IFS 125HR Fourier transform spectrometer (Nizhny Novgorod, Russia) in the region of 650–4400 cm − 1 and analyzed in the Dyad and Pentad region. The 9208 transitions belonging to the seven "cold" bands (6987 transitions) of the Dyad and Pentad and to the nine "hot" Dyad–Pentad bands (2221 transitions) were assigned and theoretically analysed in the frame of the effective Hamiltonian model. The obtained set of 68 fitted parameters reproduces the initial 9208 experimental line positions with the d r m s = 2.82 × 10 − 4 cm − 1. [ABSTRACT FROM AUTHOR]

Abstract In this study, well-aligned single-walled carbon nanotube (SWCNT) films were utilized as lamellae to prepare a multifunctional nanocomposite by a feasible 'layer-by-layer' preparation method. This structural design can not only dramatically reduce the agglomeration effect of SWCNTs, but also achieve high in-plane stiffness. It was found that the well-aligned SWCNT films contribute to the high stress-transfer between CNTs and present good wettability with epoxy matrix, thereby improving the mechanical enhancement. Interestingly, this laminated structure possesses distinct electrical behaviors under different loading conditions. The electrical resistance linearly increases with the increase of in-plane tensile strain but is insensitive to bending. This work could provide in-depth understanding on the mechanical and electrical properties of CNT-based laminated nanocomposites. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Breath analysis is an emerging field in gas sensor technology aiming for the next generation of hand-held and non-invasive medical diagnostic and monitoring devices. Often unrecognized, however, remains the importance of correct and standardized breath sampling, a prerequisite for meaningful breath analysis. Here, a simple and modular sampler design is presented that enables monitored breath extraction for reproducible and online gas sensor analysis. It consists of an inlet to monitor airway pressure and CO 2 concentration online during exhalation and a tube to capture and buffer (20–40 s) end-tidal breath to meet prolonged exposure requirements of some gas sensors. Demonstrated on the example of acetone, a breath marker for fat burn, this sampler is suitable for continuous (refreshment ∼100 s) and reproducible online breath analysis, as validated by state-of-the-art proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS). Most interestingly, even short breath pulses down to 1 s result in reliable determination of end-tidal acetone concentrations while it is severely underestimated when sampling is not done properly. Finally, this sampler is applied to detect breath acetone with solid-state Si-doped WO 3 sensors in humans. The proposed sampler can be connected to various types of gas sensors and applied flexibly for other breath markers (including isoprene, ethanol and methanol). [ABSTRACT FROM AUTHOR]

Abstract The Ca2+-Mn2+ doped LaAlO 3 was prepared by solid state reaction method, and the effects of different doping content of Ca2+ and Mn2+ ions on the infrared radiation properties of LaAlO 3 were investigated. The result showed that after doping Ca2+ and Mn2+ ions, the infrared radiation properties of LaAlO 3 significantly increased. When 40 mol% Ca2+ and 50 mol% Mn2+ ions were doped into LaAlO 3 , the average emissivity in the wavelength range of 1–22 µm was up to 0.90, which was higher than pure LaAlO 3 (0.71). The enhancement of infrared radiation properties of LaAlO 3 was mainly due to the decrease of band gap of LaAlO 3 , the increase of hole carriers absorption of energy, and the increase of lattice vibration absorption after doping Ca2+ and Mn2+ ions. Ca2+-Mn2+ doped LaAlO 3 with high infrared radiation properties shows application prospect in the high temperature oxidation environment. [ABSTRACT FROM AUTHOR]

A solid state diode pumped laser transmitter in a wide range of temperature operation is investigated. The system is a compact diode side pumped pulsed Nd:YAG laser that works in a wide temperature range from −15 to +60° C. Temperature distribution in laser head and laser rod is analyzed using a Finite Element method and LASCAD laser analyzer. The laser system produces more than 100 mJ and 55 mJ energy in free running and Q-switched mode, respectively. [ABSTRACT FROM AUTHOR]

Cu or Fe or Co substituted off-stoichiometric Ni-Mn-Sn films of 500 nm thickness were deposited on Si (1 0 0) substrate by dc magnetron sputtering at ambient temperature and then annealed ex situ at 550 °C for 1 h under high vacuum. X-ray diffraction and atomic force microscopy analyses showed that the annealed films exhibited high degree of crystalline order with cubic L2 1 phase. Magneto-static evaluation of the films established room temperature ferromagnetic order with easy axis of magnetization along the film plane in all the annealed films. The ratio of magnetic resonance and magnetic saturation ( M r / M s ) increased drastically upon Co substitution. The analysis of polar angle dependence resonance field ( H r ) and resonance linewidth (Δ H ) measurement using resonant cavity FMR technique revealed the presence of negative effective perpendicular magnetic anisotropy ( K 1 ) and very low Gilbert damping constant (α) in all the films. [ABSTRACT FROM AUTHOR]

The magnetic characteristics of Pd thin films on Fe(1 1 0) were investigated by means of Magnetic Circular Dichroism in the Angular Distribution of photoelectrons (MCDAD). For uncovered Fe it was found that significant photoelectron intensity differences occur for electrons emitted from the 3d band near the Fermi level in the situation of a fixed helicity of the incoming circularly polarized radiation and opposite magnetization of the magnetic layer. The corresponding MCDAD asymmetry shows a strong dependence on the excitation energy in the VUV range and exhibits values up to about 10%. After deposition of Pd in the submonolayer regime up to a thickness of a few layers, the new features which are present in the photoemission spectra exhibit asymmetries, too. A strong hybridization takes place at the interface which is due to the intermixing of Pd 4d and Fe 3d states. This interface state shows no dispersion and no change of the asymmetry value for different photon energies. Additionally, the sign of the asymmetry is opposite to that of the Fe substrate. The reason is the strong hybridization which results not in a rigid band shift as found for less-interacting adsorbates but in new states being different in the majority and minority spin band. As a consequence, the interface layer exhibits an induced magnetic polarization. The structure near the Fermi energy exhibit the same sign of the asymmetry but with lower values. For a thickness of 3 monolayers the spectrum is comparable to bulk measurements and shows no MCDAD asymmetries in the entire binding energy region. [ABSTRACT FROM AUTHOR]

We reported the low-temperature high performance IGZO TFTs by solution processing. The influence of IGZO composition over broad range on thin films and devices properties were investigated by a wide range of characterization techniques. The schematic of TFT solution-processed IGZO TFTs mobility with different compositions has been obtained. In order to achieve decent TFT performance, the In content should be much high for solution-processed IGZO TFTs. The optimal solution-processed IGZO TFTs with In:Ga:Zn = 5:1:1 composition exhibited a large mobility of 9.1 cm 2  V −1  s −1 , low subthreshold swing of 0.22 V/decade, and high on/off ratio of 10 6 at 300 °C processing temperature. [ABSTRACT FROM AUTHOR]

Abstract Extruded Mg–(6%Al)–(1%Zn) ∼ (AZ61) alloy powder was applied as softener matter and grains sizes promoter in narrow range to replace on magnesium sites of Mg 1-x A x B 2 superconductor (where, x = 0.0,0.025,0.050,0.075 and 0.1 mol and A = AZ61) alloy). Samples were synthesized via high temperature solid state reaction technique depending upon diffusion mechanism of Mg -vapor ions through added A-boron-matrix at 760 °C. Micro-structural features and grains sizes averages were estimated and monitored by both of 3D-AFM and SE-microscopy. Mechanical tensile was recording promising results with maximum tensile value of 52.3 MPa is for sample with x = 0.075 mol which is better than pure MgB 2 (33.8 MPa.) by promotion ratio∼ 54.73%. [ABSTRACT FROM AUTHOR]

NiCo 2 O 4 has been selected as an oxidizer to realize the nanothermite film for the first time in this study. The NiCo 2 O 4 /Al core-shell nanowires (NWs) thermite film has been fabricated using a facile hydrothermal-annealing synthesis method and a controllable magnetron sputtering process. The as-obtained NiCo 2 O 4 /Al NWs thermite film shows a uniform structure and distribution on the substrate, with a favorable interfacial contact between the bimetallic oxide and the fuel at the nanoscale. It is found that the quantity of Al plays a key role in the total heat release magnitude. The maximal heat release of the NiCo 2 O 4 /Al nanothermite film has reached 2076.0 J/g at the optimal Al deposited thickness of 450 nm with the obtained optimum Al/NiCo 2 O 4 molar ratio of 4.9. Moreover, this design strategy is highly compatible with microelectromechanical systems (MEMs) and it can be applied to realize other nanothermites composed by bimetallic oxide and fuel. [ABSTRACT FROM AUTHOR]

Abstract A crack-free and dense, yet thick lead lanthanum zirconium titanate (PLZT; P 0.92 L 0.08 Z 0.65 T 0.35) film was achieved by single-step, non-repetitive spin-coating of PLZT sol-gel chemically modified with poly(vinylpyrrolidone) (PVP). Incorporation of PVP into the precursor solution could be highly beneficial for prohibiting cracks during the condensation reaction of spin-cast gel film and controlling the film thickness. Close examination by using optical microscopy, X-ray diffraction, Raman spectroscopy, and scanning electron microscopy enabled compositional and structural characterization of PLZT films on both transparent sapphire and flexible plastic substrates before and after the laser lift-off process. Such dense and crack-free PLZT film with thickness ranging from 2.5 to 3.4 μm was successfully applied for fabricating flexible piezoelectric energy harvester. This study can be further extended to prepare other crack-free, dense piezoelectric films, thus offering a facile and robust pathway to the fabrication of the piezoelectric energy harvesting devices. Highlights • A versatile approach for micrometer thick and crack-free piezoelectric film is proposed. • Cracks are prohibited by incorporation of poly(vinylpyrrolidone) (PVP) into the precursor solution. • The lead lanthanum zirconium titanate (PLZT) film is safely transferred on to a flexible substrate. • A flexible PLZT piezoelectric energy harvester is fabricated. [ABSTRACT FROM AUTHOR]

Abstract Ni/Ni-Cr thin film thermocouples were deposited by means of DC magnetron sputtering for the application in plastic extrusion dies. In order to ensure the application of the thermocouples on complex surfaces, a thermally sprayed Al 2 O 3 layer was used between the substrate and the thin films for thermal insulation and electrical isolation. The study includes the deposition, characterization, calibration, and validation of thin film thermocouples. The influence of the composition (10 at.-%, 20 at.-% and 30 at.-% Cr) was analyzed concerning mechanical and electrical properties. It was found out that the electrical resistance increases with the temperature and the Cr-content due to a decreasing crystallite size. By means of a scratch-tester and nanoindentation, a higher scratch load and hardness were observed for larger Cr-contents on the thermally sprayed Al 2 O 3 coating. Despite the composition, the influence of the size as well as the thickness of the thermocouples were analyzed regarding the Seebeck coefficient. Independent from the size and Cr-content, all thermocouples feature a comparable Seebeck coefficient of about 40 μV/K. This high coefficient is similar to that of wire thermocouples, showing a low number of defects in the thin films. The ceramic coating features a thermal insulation of about 20 °C at 200 °C, allowing a more accurate measurement of the ambient medium. Highlights • Ni/Ni(10,20,30)Cr thin film thermocouples were deposited on thermally sprayed Al 2 O 3. • The thermocouples were deposited with different sensor sizes and calibrated. • The Al 2 O 3 coating reduces the temperature influence of the substrate. • All Ni Cr alloys show a comparable high Seebeck coefficient of 40 μV/K. [ABSTRACT FROM AUTHOR]