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Nanocrystals can be produced as a dry powder for inhalation (DPIs) to deliver high doses of drug to the lungs, owing to their high payload and stability to the shear stress of aerosolization force. Furthermore, lipid-coated nanocrystals can be formulated to improve the drug accumulation and retention in lung. The present work involved the fabrication of paclitaxel nanocrystals using hydrophilic marine biopolymer fucoidan as a stabilizer. Thereafter, fabricated nanocrystals (FPNC) were surface-modified with phospholipid to give lipid-coated nanocrystals (Lipo-NCs). The nanocrystals were fabricated by antisolvent crystallization followed by the probe sonication. The lipid coating was achieved by thin film hydration followed ultrasonic dispersion technique. Prepared nanocrystals were lyophilized to obtain a dry powder of FPNC and Lipo-NCs, used later for physicochemical, microscopic, and spectroscopic characterization to confirm the successful formation of desired nanocrystals. In-vitro and in-vivo investigations were also conducted to determine the role of nanocrystal powder in pulmonary drug delivery. Lipo-NCs exhibited slower drug release, excellent flow properties, good aerosolization performance, higher drug distribution, and prolonged retention in the lungs compared to FPNC and pure PTX. Lipid-coated nanocrystals can be a novel formulation for the maximum localization of drugs in the lungs, thereby enhancing therapeutic effects and avoiding systemic side effects in lung cancer therapy. [Display omitted] • Sub-micron sized PTX loaded Lipo-NCs were prepared for pulmonary delivery. • The NCs exhibited improved dissolution due to ∼10-fold effective surface area. • Aerosolization performance revealed deep lung distribution capability of NCs. • Lipo-NCs showed superior lung accumulation with minimal systemic distribution. • Lipo-NCs is ideal for pulmonary delivery of PTX in localized lung cancer therapy. [ABSTRACT FROM AUTHOR]

Here, we present the low temperature magnetic behaviour of epitaxial La0.7Ca0.3Mn0.85Al0.15O3 (LCMAO) thin film through a series of DC magnetic measurements. Overall behaviour inferred from the magnetization measurements indicate that the magnetic phases created due to Al doping induced inhomogeneous distribution of Mn3+ and Mn4+ ions and oxygen vacancies present in the system act like superspins, and the strong interaction among themselves results in the superspin glassy behaviour. Interactions among the superspins are marked by the aging and zero filed memory effects. The glassy magnetic phase in LCMAO is found to follow the hierarchical model of spin glasses. [ABSTRACT FROM AUTHOR]

In this paper, we describe a novel dispersion tailored properties of surface plasmon resonance (SPR) sensor assisted by Teflon and metamaterial layers. The dispersion property and the excitation methods of surface plasmon (SP) waves have been great significance in sensor design. Most of the time, SPR sensor designed for biosensing has been dual mode and its side lobes in dispersion graph can significantly reduce the sensitivity. We propose a design of as many as five-mode SP sensor assisted by Teflon and metamaterial layers. A new sensing theory for exploring highly dispersion tailored properties of multilayer sensor structure is design for efficient biorecognition. The proposed design scheme is able to completely remove the side lobes in the dispersion graph by properly controlling the Teflon layer, thin gold film, and metamaterial thickness for the case of multimode SPR sensor. To the best of our knowledge, dispersion tailored properties of multimode SP sensor assisted by Teflon and metamaterial layers together have not been explored and analyzed. The standard matrix method is applied to calculate the various performance parameters of the sensor. Experimental validation has been done with available results for a specific case. [ABSTRACT FROM AUTHOR]

Abstract Specific plasma engineering based synthesis can induce interesting photocatalytic antibacterial activities in TiO 2 films. This work presents the combination of pulsed DC (PDC) plasma with inductively coupled plasma (ICP) to synthesize undoped and nitrogen doped (N-doped) TiO 2 thin films using magnetron sputtering. The surface properties of resulting films were systematically analyzed in detail and correlated to the photocatalytic antibacterial activity against Gram negative Escherichia coli (E.coli). The addition of ICP source to PDC discharge generated TiO 2 films with enriched surface roughness due to the bombardment of highly activated species on the substrate. The ICP assisted films exhibited the morphology of nanoclusters with clear defined boundaries, higher O content and higher surface wettability. It was found that the films deposited with N-doping and addition of ICP source significantly increased the eradication of bacteria both in dark as well as in white light (artificial indoor light). Higher antibacterial activity of N-doped TiO 2 films in white light has been explained by photocatalytic degradation mechanism. Graphical abstract Image 1 Highlights • N-doped TiO 2 films have been deposited with tunable surface topography. • The surface topography and surface chemistry have been tailored through precise control of plasma species. • The high energy plasma produces the surfaces with higher wettability. • N-doped films with higher surface roughness exhibit significantly enhanced photocatalytic antibacterial activity. [ABSTRACT FROM AUTHOR]

Optimization of substrate heating during sputtering processes is essential to obtain desired microstructures of deposited thin films, as it provides the required energy flux during the nucleation and growth. In this work, Ge 2 Sb 2 Te 5 thin films were prepared by a pulsed-DC magnetron sputtering process at optimized plasma conditions (pulsed frequency and pulse reversal time). The effect of substrate heating, in temperature range of 250–450 °C, was systematically investigated on the process throughput and various properties i.e. microstructure, morphology, atomic composition, carrier concentration, mobility and Seebeck coefficient of deposited films. The substrate heating was found to be required to obtain films in cubic crystalline phase. Through the optimization of substrate temperature, process throughput and surface properties, electrical properties as well as thermoelectric power factors were enhanced. The maximum power factor value of thin films was achieved as 0.77 mW m –1  K –2 for the substrate temperature as 400 °C. [ABSTRACT FROM AUTHOR]

Ti doped ZnO (TZO) thin films are stabilized by means of sputtering on quartz substrates and their structural, optical and electronic structure studies are carried out. The effect of different substrate temperature during growth and post deposition annealing effect is emphasized in TZO films. Structural characterization reveals that the TZO films have a wurzite phase with (0001) preferred orientation and lattice strain tends to relax at higher growth temperature and lower growth rate. Crystallite size, lattice strain and the band gap demonstrate dependency on deposition parameters. Moreover, these are strongly influenced by post deposition annealing treatment. The changes induced in the electronic structure of TZO films due to varying deposition parameters and post annealing treatment are understood through X-ray absorption spectroscopy and X-ray absorption near-edge structure measurements. The secondary ion mass spectrometry predicts that concentration of Ti in TZO film is laterally homogeneous but is vertically modulated upon post annealing while the Zn and O have followed stable concentration profile. [ABSTRACT FROM AUTHOR]

Novel designs of magnetron sputtering sources provide desired control over plasma parameters for efficient use of mass and energy transport during the deposition of thin films. Here, a cup-like magnetron source, comprising a base and a cylinder part, is developed and diagnosed for deposition of transparent conductive Al doped ZnO thin films. The coupling of the base or/and cylinder parts, applied power and working pressure are systematically varied and consequent effects on the plasma density, electron temperature, and substrate temperature are studied. The sensitive optical emission and absorption spectroscopic results of plasmas reveal that base source mainly delivers the Zn ionic species whereas coupling of cylinder source induces higher ion-electron recombination and lowering the substrate temperature. The present source is capable of producing Al doped ZnO thin films with resistivity in the range of 5 × 10 −2 Ωcm to 12.1 Ωcm and process throughput close to 40 nm/min under conditions of plasma induced substrate temperature ≤60 °C. The obtained values have promising applications for flexible electronics. [ABSTRACT FROM AUTHOR]

Electrically-conductive nanocrystalline carbon films, having non-toxic and non-immunogenic characteristics, are promising candidates for reusable medical devices. Here, the pure and N- doped nanocrystalline carbon films are deposited by the assistance of inductively coupled plasma (ICP) in an unbalanced facing target pulsed-DC magnetron sputtering process. Through the optical emission spectroscopy study, the role of ICP assistance and N-doping on the reactive components/radicals during the synthesis is presented. The N-doping enhances the three fold bonding configurations by increasing the ionization and energies of the plasma species. Whereas, the ICP addition increases the plasma density to control the deposition rate and film structure. As a result, sputtering-throughput (deposition rate: 31–55 nm/min), electrical resistivity (4–72 Ωcm) and water contact angle (45.12°–54°) are significantly tailored. Electric transport study across the surface microchannel confirms the superiority of N-doped carbon films for sterilization stability over the undoped carbon films. [ABSTRACT FROM AUTHOR]

Thermoelectric measurement is an exhaustive exercise for the case of thin films, requiring meticulous attention to the thermal contact interfaces and the instrumentation. Usually, different set-ups are combined for the temperature dependent measurement of different thermoelectric key quantities. Here, a facile 6-probe measurement set-up is presented, which can measure Seebeck coefficients and electrical properties of thin films in the temperature range of 300 K–600 K. Using this set-up, the thermoelectric properties of Ge 2 Sb 2 Te 5 thin films, prepared with pulsed DC magnetron sputtering method are studied. The effects of working pressure, post-deposition thermal treatment and variation of film thickness on the microstructure, surface, electrical and thermoelectric properties are investigated systematically. Plasma diagnostics, performed using optical emission spectroscopy provided the information about various radicals' excitations and the electron temperature. Microstructural studies show the phase transformation from amorphous to metastable cubic phase. FESEM study exhibits highly dense films with uniform grains compactness. It has been found that lowering average crystallite size by optimum electron temperature and pressure conditions governs the enhancement in Seebeck coefficient. The throughput of process > 400 nm/min, and obtained Seebeck coefficients values 271.50 μV/K are highly promising for industrial utilization. [ABSTRACT FROM AUTHOR]

Highly transparent, low resistive pure and Sb, Zn doped nanostructured SnO 2 thin films have been successfully prepared on glass substrates at 400° C by spray pyrolysis method. Structural, electrical and optical properties of pure and Sb, Zn doped SnO 2 thin films are studied in detail. Powder X-ray diffraction confirms the phase purity, increase in crystallinity, size of the grains (90–45 nm), polycrystalline nature and tetragonal rutile structure of thin films. The scanning electron microscopy reveals the continuous change in surface morphology of thin films and size of the grains decrease due to Sb, Zn doping in to SnO 2 . The optical transmission spectra of SnO 2 films as a function of wavelength confirm that the optical transmission increases with Sb, Zn doping remarkably. The optical band gap of undoped film is found to be 4.27 eV and decreases with Sb, Zn doping to 4.19 eV, 4.07 eV respectively. The results of electrical measurements indicate that the sheet resistance of the deposited films improves with Sb, Zn doping. The Hall measurements confirm that the films are degenerate n-type semiconductors. [ABSTRACT FROM AUTHOR]

• N+ ion implantation induced modifications in the VO 2 films were studied. • N+ ion implantation has resulted in downward shift in structural transition temperature. • VO 2 film with implantation dose of 1 × 1015 ions/cm2 N+ ions showed metal to insulator transition at room temperature. Modifications in the structural and electronic properties of VO 2 films induced by N+ ion implantation were investigated. VO 2 films prepared by radio frequency (RF) magnetron sputtering deposition on quartz substrate were subjected to the N+ ion beam with 55 keV at different fluences (1 × 1015 and 1 × 1016 ions/cm2). Compared with the pristine VO 2 film (Tc ∼ 342 K), structural and electrical phase transition temperatures were shifted around room temperature in the N+ ion implanted sample (fluence = 1 × 1015 ions/cm2). Furthermore, a higher fluence of N+ ions (fluence = 1 × 1016 ions/cm2) had significantly modified the crystalline structure of VO 2 thin film, and a metallic behaviour was clearly noticed in the entire temperature range between 240 K and 373 K under this study. N+ ion implantation effectively induces the changes in the electronic structure of VO 2 thin films, which are further confirmed by the X-ray absorption spectroscopy (XAS) measurements. [ABSTRACT FROM AUTHOR]

Ag nanoparticles (NPs) embedded in a zirconium oxide matrix in the form of Ag:ZrO nanocomposite (NC) thin films were synthesized by using the sol-gel technique followed by thermal annealing. With the varying of the concentration of Ag precursor and annealing conditions, average sizes (diameters) of Ag nanoparticles (NPs) in the nanocomposite film have been varied from 7 to 20 nm. UV-VIS absorption studies reveal the surface plasmon resonance (SPR)-induced absorption in the visible region, and the SPR peak intensity increases with the increasing of the Ag precursor as well as with the annealing duration. A red shift in SPR peak position with the increase in the Ag precursor concentration confirms the growth of Ag NPs. Surface topographies of these NC films showed that deposited films are dense, uniform, and intact during the variation in annealing conditions. The magnitude and sign of absorptive nonlinearities were measured near the SPR of the Ag NPs with an open-aperture z-scan technique using a nanosecond-pulsed laser. Saturable optical absorption in NC films was identified having saturation intensities in the order of 10 W/m. Such values of saturation intensities with the possibility of size-dependent tuning could enable these NC films to be used in nanophotonic applications. [ABSTRACT FROM AUTHOR]

Abstract: Ag:ZrO2 nanocomposite thin films have been synthesized by a modified sol–gel technique. The effect of post-deposition treatments i.e. thermal annealing and UV irradiation on micro-structural, chemical and optical properties of nanocomposite thin films have been studied by a transmission electron microscope, X-ray photoelectron spectrophotometer and UV–vis spectrophotometer. Films deposited with a polymeric ZrO2 sol containing Ag+ ions when treated with either thermal annealing or with UV irradiation exhibit formation of Ag:ZrO2 nanocomposite thin films via decomposition of Ag2O3 into metallic Ag. The formed Ag nanoparticles are found predominantly in spherical shape and density of Ag nanoparticles increases with increase in annealing duration for a particular concentration of Ag precursor. A protocol is provided to tailor the surface plasmon resonance-induced absorption peak at wavelength from 454 to 586nm. These nanocomposite thin films show saturable absorption and exhibit high value of non-linear absorption coefficient. [ABSTRACT FROM AUTHOR]

• Structural phase transition in VO 2 thin films is modulated by annealing temperature. • Increasing annealing temperature led to increase in spectral weight of V 3 d || states. • Intermediate M2 phase is emerged in VO 2 films annealed at higher temperature (T > 510 °C). • Infrared (IR) switching temperature and IR switching performance is tailored by varying the annealing temperature. Monoclinic M1 to rutile structural phase transition (SPT) in thermochromic VO 2 is accompanied by the insulator to metal transition and transition from an infrared (IR) transparent to IR opaque phase. Fine control over the phase stabilization and the functional properties without additional doping can offer the ability to tailor VO 2 thin films for their respective applications. In this work, post deposition thermal annealing was used to control the phase stabilization and the modulation in thermochromic performance of polycrystalline VO 2 thin films. Monoclinic M1 to rutile SPT in VO 2 thin films was tracked by in-situ temperature dependent synchrotron X-ray diffraction measurements and an increase in the SPT temperature was observed with increasing annealing temperature. Intermediate monoclinic M2 phase emerges near the SPT temperature at higher annealing temperature. Temperature dependent X-ray absorption spectroscopy (XAS) measurements revealed the higher electron correlation effect among the V 3 d || states across the phase transition in VO 2 thin film having the intermediate phase. Spectral weight of V 3 d || states was found to increase with the annealing temperature. Lower annealing temperature drives the IR switching temperature towards room temperature while the higher annealing temperature improves the IR switching performance of VO 2 thin films. [ABSTRACT FROM AUTHOR]

• Temperature dependent optical properties studies on Nd 2 CoMnO 6 -SrTiO 3 thin- films. • Strongly softened photon mode position below T c. • Temperature dependent Raman spectroscopic studies in detail. • Energy transfer within the non- centrosymmetric structure. The detailed temperature dependent optical properties in double perovskite type Nd 2 CoMnO 6 -SrTiO 3 (NCMO-STO) thin films have been investigated the experimentally grown epitaxial thin films on STO substrates using pulsed laser deposition technique. At first order room temperature, a Raman spectrum of NCMO/STO thin films are measured in unpolarized geometry using 488 nm laser excitation and confirms its monoclinic bulk like crystal structure. Temperature dependent Raman spectra confirms the appearance of a sharp, intense phonon mode below magnetic ordering, signifies structural phase transition accompanied by magnetic transition. The phonon mode position and line-width are fitted by anharmonic model and found to be strongly softened phonon mode position below T C and strong spin-phonon coupling in the system. The excitation spectrum and the bandgap in NCMO film confirms the yellow emission resulting from energy transfer within the non- centrosymmetric structure. [ABSTRACT FROM AUTHOR]

• Developing Cu:C nanocomposite films using plasma cosputtering process for microstructure control. • Control of surface morphology and porosity for release of Cu ions. • Correlation of film composition and film structure with antibacterial activity. This study presents magnetron plasma co-sputtering process for the synthesis of carbon thin films embedded with Cu nanoparticles (NPs). Varying the working pressure and power density of Cu target, induces control over morphology as well as the amount of Cu ions release while interacting with bacterial aliquots. The crystallographic observations present the formation, growth and orientation of crystals in Cu NPs. Raman spectroscopy depicts that increase in working pressure contributes to the development of carbon matrix structure dominating sp3 hybridizations. The variation in chemical structure with varying the plasma conditions is studied by high resolution x-ray photoelectron spectroscopy. The antibacterial activity, observed against staphylococcus aureus (S. aureus) and Escheria coli (E. coli), is strongly related to the release of Cu ions from the films. The nanocomposite films releasing Cu ions ∼1.68 µg/g of the aliquot, completely inhibit the bacterial growth. Obtained excellent antibacterial activity of presented Cu embedded nanostructured carbon films proves these films as a promising candidate in bio-medical applications. [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO 2) is one kind of desired thermochromic material for many smart devices because of its notable temperature-responsive infrared modulation and metal−insulator transition with underlying structural phase transition (SPT). Understanding on the tuning of these properties in an anticipated manner is essential to accomplish device realization. Here, we report the annealing time induced modifications in SPT and the thermochromic properties of VO 2 thin films. Using RF sputtering deposition, VO 2 thin films were grown at room temperature and their ex-situ annealing was carried out at 600 °C for different time from 2 min to 60 min. Structural, electronic and thermochromic properties of these films were investigated. VO 2 thin films samples annealed for longer time exhibit larger crystallite size, higher surface roughness and SPT temperature, and the reduced hysteresis width of SPT during heating and cooling cycle. X-ray absorption spectroscopy results indicate that the variation in the annealing time do not alter the electronic structure significantly. Nevertheless, VO 2 thin film samples with prolonged annealing display higher IR transmittance modulation across the SPT. • VO 2 thin films were stabilized by giving post deposition annealing treatment to room temperature deposited films. • Variation in annealing time modifies the structural phase transition of VO 2 thin films. • Thermochromic properties of VO 2 thin films were tailored by controlling the annealing time. [ABSTRACT FROM AUTHOR]

Bilayer thin film samples consisting of colossal magnetoresistance manganite La 0.7 Ca 0.3 MnO 3 (LCMO) and superconducting cuprate YBa 2 Cu 3 O 7−δ (YBCO) were stabilized by means of pulsed laser deposition techniques on single crystal SrTiO 3 (001) substrate. The X-ray diffraction measurements confirm the epitaxial relationship of grown bilayer samples. The functional properties of the LCMO/YBCO bilayer were explored through magnetic and electrical transport measurements. The magnetization curve of LCMO/YBCO bilayer sample retains the characteristic ferromagnetic-paramagnetic transition of LCMO and superconducting transition of YBCO. The electrical resistivity was found to show different trend around the superconducting transition depending upon the four probe electrical contacts configuration on bilayer samples and the obtained results lead to direct visualization of proximity effect. A change in sign of magnetoresistance near the superconducting and metal to insulator transition temperature is observed which is attributed to the intrinsic property of YBCO and LCMO layers. [ABSTRACT FROM AUTHOR]

Zero field cooled spontaneous exchange bias (SEB) is observed in self-assembled nanocomposite thin films of La 0.7 Sr 0.3 MnO 3 (LSMO):NiO grown on single crystal line SrTiO 3 (001) substrate by pulsed laser deposition. SEB is displayed by the asymmetry in the hysteresis loop of the composite film along with the field cooled conventional exchange bias (CEB) effect. The training effect shows that exchange bias relaxation is disorder mediated. It is revealed from DC magnetization measurements that such nanocomposite film divulges spin glass like behaviour, arising due to competing ferromagnetic and antiferromagnetic interactions at the assorted interfaces of ferromagnetic LSMO and antiferromagnetic NiO. X-ray magnetic circular dichroism (XMCD) measurements discern that SEB is mainly originating due to ferromagnetic coupling of unstable interfacial antiferromagnetic spin due to NiO with the ferromagnetic LSMO at the disordered interface. These results of self-assembled thin films provide a useful input to realize and understand microscopic origin of SEB for device application. • Self-assembled nanocomposite thin films of La 0.7 Sr 0.3 MnO 3 (LSMO):NiO grown on SrTiO 3 (001). • Zero field cooled spontaneous exchange bias (SEB), field cooled conventional exchange bias (CEB). • The training effect shows that exchange bias relaxation is disorder mediated. • Magnetization measurements reveals the presence of interfacial disordered glass like behaviour. [ABSTRACT FROM AUTHOR]

Transparent-flexible thermoelectric materials are attractive for future small-sized consumer electronics, the internet of things, and wearable devices. The microstructural evolution and subsequent thermoelectric properties of Ti 1%.at-doped ZnO thin films, grown on polyimide flexible substrates, are presented. The thin films were grown using radio frequency a magnetron sputtering method followed by annealing for 60 min at temperatures of 200–400 °C under vacuum atmosphere. Post-annealed films demonstrate a hexagonal Wurtize structure. It is found that the annealing helped to relax residual stresses in the thin films, subsequently leading to enhanced charge concentration, carrier mobility, mean free path, and density-of-states effective mass. The thin film, annealed at 300 °C, illustrates the highest power factor of the films measured at room temperature at 19.10 μW m−1 K−2. Further increases in the annealing temperature suggest Ti2+ diffuses into the ZnO lattice and in turn disturbs the crystalline structure; this results in a reduction of the power factor to 9.32 μW m−1 K−2 at an annealing temperature of 350 °C. [ABSTRACT FROM AUTHOR]

Rhombohedral GeSb 5 Te 10 thin films are synthesized onto Al 2 O 3 substrate by a pulsed-DC magnetron sputtering method using a target prepared by hot-pressing method. Thermoelectric properties of these films are studied as a function of temperature from room temperature to 773 K and correlated to the microstructural and surface properties. It is found that the phase transformation from amorphous to rhombohedral phase of GeSb 5 Te 10 , observed in temperature range 473–773 K, involved lattice-swelling and atomic diffusion within the crystalline structure. The completion of phase transformation at annealing temperature 673 K minimized the average crystallite size of thin film and enhanced the Seebeck coefficients (~140 μVK−1) and thermoelectric power factor (~4.5 mWm−1 K−2). Molecular orbital simulations of small cluster model, performed using linearly decreasing scattering variable along with the temperature dependent Fermi energy for onto determining the electrical and thermoelectric properties, were found in agreement to the experimental results. [ABSTRACT FROM AUTHOR]

As water availability becomes a growing challenge in various regions throughout the world, desalination and wastewater reclamation through technologies such as reverse osmosis (RO) are becoming more important. Nevertheless, many open questions remain regarding the internal structure of thin-film composite RO membranes. In this work, fully aromatic polyamide films that serve as the active layer of state-of-the-art water filtration membranes were investigated using high-angle annular dark-field scanning transmission electron microscopy tomography. Reconstructions of the 3D morphology reveal intricate aspects of the complex microstructure not visible from 2D projections. We find that internal voids of the active layer of compressed commercial membranes account for less than 0.2% of the total polymer volume, contrary to previously reported values that are two orders of magnitude higher. Measurements of the local variation in polyamide density from electron tomography reveal that the polymer density is highest at the permeable surface for the two membranes tested and establish the significance of surface area on RO membrane transport properties. The same type of analyses could provide explanations for different flux variations with surface area for other types of membranes where the density is distributed differently. Thus, 3D reconstructions and quantitative analyses will be crucial to characterize the complex morphology of polymeric membranes used in next-generation water-purification membranes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Flexible transparent In/Ga co-doped ZnO (IGZO) thin films were achieved to fabrication on polyimide (PI) substrates by RF-magnetron sputtering method. • The microstructural evolution with annealing processing are enhanced the power factor to be achieved to 16.9 μW m−1 K−2. • Uni-leg thermoelectric thin film modules of four elements as fabricated were achieved the maximum power generation was found 3.2 nW at ΔT = 120 K. Transparent-flexible thermoelectric thin films have immense potential as power supplies for future small-sized consumer electronics, the internet of things, and wearable devices. Here, we report the thermoelectric properties of dual Ga and In doped ZnO films (IGZO) deposited on a polyimide substrate with post-thermal treatment in vacuum along with fabricating 4-unileg flexible IGZO thermoelectric devices. All the as-deposited and annealed IGZO films are the preferred (0 0 2) orientation and under tensile stress. The post-thermal treatment controls the dopant substitution/diffusion in the host ZnO lattice affecting the film crystallinity, residual stress, and thermoelectric properties. Among the films, the IGZO film annealed at 250 °C has the best power factor of 16.9 μWm−1K−2 with the largest crystal size, lowest tensile stress, highest carrier concentration, and lowest density-of-state effective mass. The practical application of flexible IGZO films was also reported via a 4-unileg-IGZO films thermoelectric module, which achieved an output power about 3.2 nW at ΔT = 120 K. [ABSTRACT FROM AUTHOR]

In this work, homogeneous Ag-doped Sb 2 Te 3 (AST) thin films were prepared using the rf magnetron sputtering technique. Thermoelectric properties of AST films have been investigated in terms of various substrate rotation speeds (20, 40, 60, and 80 rpm) and rapid post-thermal treatments at 250 oCin a vacuum. It was found that the thickness of AST films decreases with the increase in substrate rotation speeds. An Ag atomic composition slightly increases and the other Sb and Te atomic compositions slightly decrease with the increase of substrate speed rotations. The post-thermal treatment improved film crystallinity. Carrier scatterings at the grain boundaries tend to increase the resistivity and the Seebeck coefficient. The maximum power factor of 4.60 mW m−1K−2 (ρ = 19 μΩm, S = 298 μVK−1) is obtained in the AST thin films prepared with the substrate rotation speed of 60 rpm. The practical application of AST films was also reported via a thermoelectric module of five p -AST/n-Bi 2 Te 3 thin-film pairs with its achieved output power of 1.6 nW at ΔT = 20 K. • Ag–Sb–Te (AST) thin films were fabricated by RF magnetron sputtering. • Substrate rotation speed at 60 rpm induced highly homogeneous and more uniformity of thin films. • Rapid thermal annealing has changed amorphous to crystalline thin films as well as microstructure and thermoelectric properties enhancing. [ABSTRACT FROM AUTHOR]

Pure CdO nanostructured thin films and Ag doped with 1.0, 2.0 and 4.0 wt% doping concentrations were fabricated successfully on glass substrates with a cost-effective spin coating technique. The prepared films exhibit a cubic crystal structure oriented along (111) plane. The surface morphology of the pure CdO films shows a cauliflower shape structure, becomes granular, and compact at high Ag doping concentration. Raman spectra of the films reveal LO (longitudinal optical) and TO (transverse optical) vibration modes at 406.80 cm−1 and 566.54 cm−1. The absorption of the films significantly varies with Ag doping concentrations and as a result, the electronic structure of the films is tailored. Moreover, the optical band gaps vary in the range of 1.42–1.70 eV. In addition, the optical parameters n, k were studied in correlation with Ag doping concentrations. The obtained room temperature photoluminescence spectra of the prepared films show a broad peak at ∼350 nm. The third order nonlinear optical parameters of the films were also examined systematically. • Cauliflower morphology of pure CdO films was observed as incorporation of Ag films morphology change drastically. • Interesting change in NBE peak was observed as incorporation of Ag in CdO films. • 4.0 wt% Ag doped CdO films reveals remarkable enhancement in third order nonlinear optical susceptibility. [ABSTRACT FROM AUTHOR]