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Aiming at ammonia gas detection at ambient temperature, phenoxyacetic acid (Hpoa) and 2,5-pyridinedicarboxylic acid (H2pydc) were employed to construct the isostructural [LnIII(poa)(2,5-pydc)(H2O)2]·3H2O (LnIII= EuIII(I), GdIII(II), and TbIII(III)). Their single crystal structures and photophysical properties as well as the triplet state energies of the sensitizers were characterized. Robustness and responses of Iand its composite film with poly(vinyl alcohol) (I/PVA) toward water, ammonia, and common volatile organic compounds were examined. The substantial quenching of EuIII:5D0→ 7FJby only ammonia was disclosed, and the underlying mechanism was postulated based on experimental and computational studies. Referring to EuIII:5D0→ 7F2, the response Rparameter was defined. Under ambient temperature (25–35 °C) and humidity (45–55% RH), a linear dependence of Ron ammonia concentration (0.50–10.0 ppm) was obtained from I/PVA. Based on the calibration method, the sensitivity (4.04%·ppm–1), detection limit (0.14 ppm), percentage recoveries (103–111% for 3.50, 6.50, and 8.50 ppm), and relative standard deviation (1.5–8.2%) were determined. The reuse of the film for at least 10 cycles was demonstrated with 95–97% repeatability. Limitation of the detection by extreme humidity was presented.

The new nanoporous framework [Gd4(di-nitro-BPDC)4(NO2)3(OH)(H2O)5]·(solvent) (I; di-nitro-BPDC2–= 2,2′-dinitrobiphenyl-4,4′-dicarboxylate) has been designed and synthesized through a simple one-pot reaction. In addition to its exceptional thermal and water stabilities, Iexhibited multifunctional properties. A sudden CO2uptake to a maximum of 4.51 mmol g–1(195 K and 1 bar) with notable selectivity over O2and N2(CO2/O2= 39 at 195 K and 0.10 bar, CO2/N2= 46 at 195 K and 0.10 bar) and an isosteric adsorption enthalpy of 20.7(4) kJ mol–1have been revealed. Depending on the temperature and humidity, Ialso showed distinguished superprotonic conductivities with a maximum value and activation energy of 6.17 × 10–2S cm–1(55 °C, 99 RH%, and 1 V AC voltage) and 0.43 eV, respectively. With respect to the linear dependence of conductivities on both temperature (25–55 °C at 99 RH%) and humidity (55–99 RH% at 25 °C), the potential of Iin temperature and humidity sensing was evaluated, disclosing an excellent sensing resolution and exceptional accuracy, precision, and repeatability for the measurements.

Based on the mixed phthalate (phth2–) and adipate (ad2–), [Nd2(ad)(phth)2(H2O)4] (I) and [Ln(ad)0.5(phth)(H2O)2] (Ln = EuIII(II), GdIII(III), TbIII(IV), DyIII(V), ErIII(VI), TmIII(VII), 1EuIII:10TbIII(VIII), 3EuIII:10TbIII(IX), and 5EuIII:10TbIII(X)) were synthesized and characterized. Complexes VIII–Xshow excellent ratiometric temperature sensing behavior in physiological and higher temperature ranges (303–423 K) rendered by the TbIII-to-EuIIIenergy transfer process. The efficiency of the process as illustrated through the lifetime measurements depends on both the EuIII:TbIIImole ratio and the temperature. The performance of Xin terms of relative sensitivity (Sr), temperature resolution, and measurement repeatability were determined, revealing the maximum Sr(Sm) of 1.21%·K–1at 303 K with reliable temperature resolution and excellent repeatability.

The 0-3 lead-free bismuth sodium titanate-bismuth potassium titanate-barium titanate (BNBK) ceramic/Portland cement composites (PC) were fabricated by pressing and curing method. The influence of BNBK particle size on the dielectric and acoustic properties of 0-3 BNBK-PC composites was studied. BNBK of various median particle sizes (75, 212 and 425 μm) at 50% by volume were mixed with Portland cement to produce the 0-3 BNBK-PC composites. The dielectric constant results of composites were found to increase with increasing BNBK particle size and the dielectric constant of composite with 425 μm particle size at 1 kHz was 196. The 0-3 BNBK-PC composites in the range tested have an acoustic impedance match with concrete structure.

In this study, the fringe pattern distribution of various loads on circular disk of homogeneous acrylic in different thicknesses by using reflection polariscope technique was carried out. The load was pressed at the top and the bottom to produce the fringe patterns, which were recorded by digital camera. Then the results were analyzed. The number of isochromatic fringe pattern depends on the magnitude of force acting on the circular disk and these relation is linearly. The application of these research is used to predict stress distribution on the transparent material in the case of different dimension of the circular disk shape.

The optical spectroscopic properties of fluorescent materials were investigated using laser induced fluorescence technique. The fluorescent creams were used in this research. The sample materials were illuminated by UV laser excitation source. Then, the fluorescence spectra were recorded and analyzed by fiber optics spectrometer complied with the CIE 1931 XYZ color space which is essential for color management. The result showed that the characteristics of fluorescence spectra such as intensity, wavelength position and bandwidth in each fluorescent creams exhibited distinct characteristics in each species.

Perovskite solar cells (PSCs) are an innovative technology with great potential to offer cost-effective and high-performance devices for converting light into electricity that can be used for both outdoor and indoor applications. In this study, a novel hole-transporting layer (HTL) was created by mixing copper phthalocyanine (CuPc) molecules into a copper(I) thiocyanate (CuSCN) film and was applied to carbon-based PSCs with cesium/formamidinium (Cs0.17FA0.83Pb(I0.83Br0.17)3) as a photoabsorber. At the optimum concentration, a high power conversion efficiency (PCE) of 15.01% was achieved under AM1.5G test conditions, and 32.1% PCE was acquired under low-light 1000 lux conditions. It was discovered that the mixed CuPc:CuSCN HTL helps reduce trap density and improve the perovskite/HTL interface as well as the HTL/carbon interface. Moreover, the PSCs based on the mixed CuPc:CuSCN HTL provided better stability over 1 year due to the hydrophobicity of CuPc material. In addition, thermal stability was tested at 85 °C and the devices achieved an average efficiency drop of approximately 50% of the initial PCE value after 1000 h. UV light stability was also examined, and the results revealed that the average efficiency drop of 40% of the initial value for 70 min of exposure was observed. The work presented here represents an important step toward the practical implementation of the PSC as it paves the way for the development of cost-effective, stable, yet high-performance PSCs for both outdoor and indoor applications.

This research was conducted to study the inner filter effect on the fluorescence spectra of fluorescence dyes. The concentration effect on all of fluorescent dye solutions showed the same trend in terms of changes in fluorescence intensity spectra. At low concentrations, the fluorescence intensity increased when the concentration of fluorescent dye solution increased. However, at high concentrations, the fluorescence intensity decreased when the concentration of fluorescent dye solution increased. Interestingly, the result of fluorescence spectra in dye solutions showed that the fluorescence intensity maxima in all dye solutions were shifted to a higher wavelength (red-shift) when the concentration of fluorescent dye solution increased. The results of concentration effect on fluorescence intensity and wavelength-shift in dyes solution can be explained by inner filter effect on fluorescent dye solutions.

The experiment was conducted to study the stress distribution on a homogeneous plastic using photoelastic analysis system where the stress was observed by reflection polariscope. The circular disk of homogeneous plastic was used for study in this research. The sample was pressed at the top and bottom. The fringe patterns were produced from sample on the model being stressed, which could be observed in the bright field and dark field. The fringe patterns were recorded by digital camera. Then the results were analyzed; the fringe pattern looked different when applying various magnitudes of force because the stress distribution in sample was changed in homogeneous plastic.

In this study, leadbased ferroelectric ceramics Pb0.91La0.09Zr0.65Ti0.35O3 PLZT (9/65/35) were fabricated by solid solution method. The electrical and mechanical properties were measured by modified Michelson interferometer and Sawyer-Tower circuit to investigate electric field induced strain and polarization (s-P-E) of PLZT (9/65/35) at 30-70 °C. The induced strain and polarization were changed when the temperature was increased indicating the change of spontaneous polarization inside the ferroelectric materials.

Structure–property relationship has been performed in the lanthanum-modified lead–zirconate–titanate (PLZT) with a lanthanum content 8 and Zr/Ti ratio 40/60. The X-ray diffraction analysis, scanning electron microscopy, and sintering behavior have evidently demonstrated that it is possible to tailor the structural properties of PLZT 8/40/60. Structure of PLZT 8/40/60 had pure perovskite with tetragonal without secondary phase. Tetragonality (c/a) was observed in the range of 1.01093-1.02095. SEM micrographs were shown a development of mean grain size to clarify the development of grain after sintering processing. The result shows that increasing of sintering temperature resulted in mean grain size increasing from 1.70 to 3.08 μm. Ferroelectricity of PLZT ceramics were normal ferroelectric and dielectric constant increased with the increasing sintering temperature.

Feroelectric lead lanthanum zirconate titanate (PLZT) ceramics 9/70/30 were synthesized by conventional mixed-oxide method via a vibro-milling technique. The effect of sintering temperature and two-stage sintering method on electrical properties of PLZT ceramics was investigated. The ceramic powder was uniaxially pressed in pellets and sintered at the temperatures ranging from 1200 to 1275 °C for 4hrs and two-stage sintering temperature at 1200 °C for 4 hrs. Dielectric, ferroelectric and strain properties of ceramics were characterized by LCR meter, modified Sawyer–Tower Circuit and modified Michelson interferometric technique respectively.

In this study, (1-x)Pb0.92La0.08(Zr0.4Ti0.6)O3 - xPb (Zn1/3Nb2/3)O3 (PLZT-PZN, x = 0, 0.05, 0.10, 0.15 0.20 and 0.25) ceramics with pure perovskite were synthesized by mixed oxide synthetic route via a rapid vibro-milling technique. The ceramic pellets were sintered at 1250°C for 4 h. The phase formation and composition was investigated using X-ray diffraction. The dielectric properties of the densified samples were investigated by LCR meter as a function of temperature and frequency. It can be seen that when optimal amount of PZN was added to tetragonal Pb0.92La0.08(Zr0.4Ti0.6)O3 ceramics, the electrical properties were found to be optimal.

Hybrid-doped BaTiO3 ferroelectric ceramics Ba (Ti(0.99-x)Mn0.01Tax)O3 systems have been prepared by a conventional mixed-oxide method viavibro-milling technique. The dielectric properties at room temperature were observed under magnetic field applied parallel to electric field. The results indicate significant changes of both properties with the magnetic field. Moreover, explained in terms of the induction of magnetization by means of an electric field and induction of polarization according to domain switching of the dielectric properties under the influence of the applied magnetic field.

In this study, Bismuth-based glasses were prepared and doped with various concentration of potassium chromate. They were melted in an electrical furnace at 1250°C for 4 hours then pressed with fire frame to plate shape and annealed at 500°C for 10 min. Optical spectra were used to analyze color shade of glasses. Homogeneity of glasses was analyzed by birefringence technique. Glasses color was changed from colorless to slightly and opaque green with an increasing amount of potassium dichromate and birefringence result showed that the glasses are non-homogenous.

This work is aimed at synthesizing lead zinc niobate powders which consist of pyrochlore phases by modified solid-state reaction via a rapid vibro-milling in difference three synthesis routes: mixed oxide precursor (PZN-M) , columbite precuresor (PZN-C) and lead niobate precuresor (PZN-P). It involves the fabrication of PZN powder and study of phase formation and local structural environment of Zn ions by using X-ray Diffraction (XRD) and X-Ray Absorption Spectroscopy (XAS) techniques that compared the amount of pyrochlore phases with perovskite phase.

In this study, Pb0.91La0.09(ZrxTi1-x)O3 ceramics ( x = 0.75, 0.70, 0.65, 0.60, 0.55 and 0.50) have been synthesized by conventional mixed oxide method via a vibro-milling technique. The effect of composition on phase formation and electrical properties of PLZT ceramics was investigated. All compositions of powders were uniaxially pressed in pellets and sintered at the temperatures of 1275°C for 2h. Phase formation, dielectric, ferroelectric strain properties of ceramics were characterized by XRD, LCR meter, modified Sawyer–Tower Circuit and modified Michelson interferometric technique respectively. In this study new materials will be systematically developed based on the material engineering approach (processing vs electrical properties).

This research was conducted to improve the ferroelectric properties of PZT based ceramics by studying the effect of sintering conditions in terms of temperature and soaking time (time of sintering) on the ferroelectric properties of ceramics in the 0.8Pb (Zr1/2Ti1/2)O3-0.2Pb (Zn1/3Nb2/3)O3 system prepared by vibro-milling mixed-oxide method. The XRD patterns of specimens showed perovskite structure for all compositions. The pyrochlore phase was not observed in this system. The sintering temperature and soaking time affects the ferroelectric properties of ceramics by the optimum sintering condition for 0.8PZT-0.2PZN ceramic is sintered at 1250°C for 2h.

Barium titanate (BT) additive in lanthanum modified lead zirconate titanate (PLZT) was used to modify the microstructure and resultant properties of (1-x) PLZT– x BT where x= 0, 0.05, 0.10, 0.15, 0.20 and 0.25. Oxide powders were synthesized by mixed oxide synthetic route via a rapid vibro-milling technique. All of samples were sintered at 1275°C with the soaking time of 4 h. The ceramic samples were investigated for phase formation and evolution, dielectric behavior and ferroelectric properties. Introduction of BT in PLZT lattice resulted in ferroelectric tetragonal-rhombohedral structure, and further increase of BT content resulted in stabilizing the ferroelectric tetragonal perovskite phase. Dielectric behavior and ferroelectric properties were examined as a function of BT content.

In this research, Barium titanate (BT) additive in lanthanum modified lead zirconate titanate (PLZT) was used to stabilize the PLZT ceramics. Oxide powders were synthesized by mixed oxide synthetic route via a rapid vibro-milling technique. It was prepared with the chemical formula of 0.95 Pb0.91La0.09 (Zr0.65Ti0.35)0.9775O3 -0.05 BaTiO3 to investigate the dielectric properties of PLZT ceramics. The modified PLZT ceramics were fabricated at variation of sintering temperatures of 1200-1275°C for 4 hours. By employing X-ray diffraction (XRD), it was found a pure perovskite with rhombohedral structure. The relaxor behavior was observed from the dielectric measurements. The suitable sintering temperature of 0.95 PLZT - 0.05 BT was 1275°C (εr=10463, tanδ=0.0125 and Tm=70°C).

Nanosized zinc oxide/lead titanate (ZnO/PT) ceramic matrix nanocomposites have been studied. Under an appropriate sintering condition, ZnO/PT ceramic nanocomposites were successfully fabricated by a pressureless sintering technique. Thermal expansion and polatization behaviors were determined by using the dilatometer. This technique measures the temperature-dependent of the strain, and the magnitude of polarization can be deduced from the sets of the thermal expansion data. The calculated electric polarization values on the ZnO/PT nanocomposite ceramics show the simple approach to determine the temperature dependence of the polarization below and around the transition temperature. Various aspects on understanding the polarization behavior and other effects in the ferroelectric are discussed.

Zinc niobate, ZnNb2O6, nanopowders was synthesized by a solid-state reaction via a rapid vibro-milling technique. The effect of milling time on the phase formation and particle size of ZnNb2O6 powder was investigated. The formation of the ZnNb2O6 phase investigated as a function of calcination conditions by DTA and XRD. The particle size distribution of the calcined powders was determined by laser diffraction technique, while morphology, crystal structure and phase composition were determined via a SEM techniques. In addition, by employing an appropriate choice of milling time, a narrow particle size distribution curve was also observed.

Effects of perpendicular compressive stress on the ferroelectric properties of ceramics in PZT-PZN system were investigated. The (1-x)Pb(Zr1/2Ti1/2)O3-xPb(Zn1/3Nb2/3)O3 or (1-x)PZT- (x)PZN (x = 0.1-0.5) ceramics were prepared by a conventional mixed-oxide method. The ferroelectric properties were measured under compressive stress applied perpendicular to an electric field direction at stress levels up to 90 MPa using a compressometer in conjunction with a modified Sawyer-Tower circuit. It was found that with increasing compressive stress the area of the ferroelectric hysteresis (P-E) loops, the maximum polarization (Pmax), and the remanent polarization (Pr) decreased, while the coercive field (Ec) remained relatively constant. These results were interpreted through the domain switching, clamping of domain walls and de-poling mechanisms.

The scaling behavior of the dynamic hysteresis of ferroelectric BaTiO3 bulk ceramics was investigated. Two sets of the scaling relation of hysteresis area against frequency f and field amplitude E0 were clearly established. Approximately, above the coercive field, the scaling took a form of  f -0.23E00.87. On the other hand, the scaling in the form of  f -0.36E03.64 was obtained under a sub-coercive field condition. While these scaling relations were generally comparable to previously reported ones, it was found that the f- and E0 exponents clearly depended on E0 and f, respectively.

Apart from aging effect, barium titanate ceramics usually subjected to the mechanical loading when it is used in electronic device. Thus, it is very interesting to investigate the influence of various compressive stresses on ferroelectric aging behavior of Ba(Ti0.99-xFe0.01Nbx)O3 , x=0.005-0.015. In this study, the P-E hysteresis loops were observed by using compressometer in conjunction with a modified Sawyer-Tower circuit. The stress level was varied from 0 to 185 MPa. The results showed that the dissipation energy, saturation polarization (Psat), remnant polarization (Pr) and the coercive field (Ec) decreased with increasing of stress. The aging behavior was still observed in acceptor-dominant of hybrid doped ceramics. The aging was also enhanced under application of the external stress. The explanation based on the defect-dipole and domain-reorientation processes was discussed.

Lead-free, bismuth sodium titanate-potassium sodium niobate piezoelectric ceramics (Bi1/2Na1/2)TiO3-(K1/2Na1/2)NbO3 have been prepared by a conventional mixed-oxide method via vibro-milling technique. The (K1/2Na1/2)NbO3 (KNN)-based compositions with a morphotropic phase boundary (MPB) have shown greater advantages over another typical lead-free piezoelectric candidate material system, (Bi1/2Na1/2)TiO3 (BNT)-based MPB materials. More importantly, when used this type of material is often subjected to self-induced or external stress. It is, therefore, of interest to investigate influence of stress on properties of the ceramics. In this study, the influences of compressive stress on the dielectric properties of BNT-KNN ceramics were investigated. The dielectric properties were determined under compressive stress applied parallel to electric field. The results indicate significant changes of both properties with the imposed compressive stress. The results were explained in terms of non-180˚ domain switching and de-aging of the dielectric properties under the influence of the applied stress.

Effects of electric field-amplitude and mechanical stress on hysteresis area were investigated in partially depoled hard PZT bulk ceramic. At any compressive stress, the hysteresis area was found to depend on the field-amplitude with a same set of exponents to the power-law scaling. Consequently, inclusion of compressive stresses into the power-law was also obtained in the form of < A – Aσ=0 > α E05.1σ1.19 which indicated the difference of the energy dissipation between the under-stress and stress-free conditions.

A perovskite-type phase of solid solution of BiFeO3-BaTiO3 powders were synthesized by a solid-state reaction via a rapid vibro-milling technique. The effect of calcination condition on the phase formation, and characterization of BiFeO3-BaTiO3 powders were investigated. The formation of the BiFeO3-BaTiO3 phase investigated as a function of calcination conditions by TG–DTA and XRD. Morphology, particle size and chemical composition have been determined via a combination of SEM and EDX techniques and vibrating sample magnetometer (VSM) was used to characterize the structures and magnetic properties of prepared samples. The rapid vibro-milling is employed for the first time in this work as a significant time-saving method to obtain single-phase BiFeO3-BaTiO3 powders.

A perovskite-type phase of Bismuth Ferrite, BiFeO3, powder was synthesized by a solid-state reaction via a rapid vibro-milling technique. The effect of calcination condition on the phase formation, and characterization of BiFeO3 powder was investigated. The formation of the BiFeO3 phase investigated as a function of calcination conditions by TG–DTA and XRD. Morphology, particle size and chemical composition have been determined via a combination of SEM and EDX techniques and vibrating sample magnetometer (VSM) were used to characterize the structures and magnetic properties of prepared samples. The rapid vibro-milling is employed for the first time in this work as a significant time-saving method to obtain single-phase BiFeO3 powders.

The compositions of Pb(Zr0.52Ti0.48)O3 doped with 1-6 mole% Nb content were prepared by a conventional mixed oxide technique. It was found that the phase formed depended on the dopant concentration. At lower concentration, the dominate phase was the tetragonal. With increasing Nb content the rhombohedral phase tended to increase. Furthermore, the Curie temperature (Tc) and dielectric constant decreased with increasing Nb concentration and the dielectric maximum peaks were broadened with more rhombohedral phase presence, causing the diffused ferroelectric-paraelectric phase transition. The impedance of the samples decreased with increasing temperature and it was also observed that the impedance increased with increasing Nb concentration.

The structure and electrical properties of Al2O3-doped 0.2Pb(Zn1/3Nb2/3)O3-0.8Pb(Zr1/2Ti1/2)O3 ceramic, which is the morphotropic phase boundary composition of the PZN-PZT system, were investigated. The addition of Al2O3 content transformed the crystal structure rom coexisting with rhombohedral to purely tetragonal structure. Furthermore, addition of Al2O3 decreased r, d33 and kp, but increased Curie temperature and enhanced the mechanical quality factor. inally, the P–E and s-E loops demonstrated decreased Pr, Ec and strain level with addition of Al2O3

Black titanium dioxide (TiO2) quantum dots (QDs) are grown by a solution‐based electrochemical process and an effect of KCl concentration on the growth is investigated. The electrochemical process is demonstrated as a simple one‐step process for the growth of black TiO2QDs in the solutions via bottom–up process. From the absorption spectra, the absorption appears for an entire visible wavelength (400–700 nm) implying a black TiO2property. The average size of the black TiO2QDs is about 4.5 nm from the transmission electron microscopy results and is similar to all KCl concentrations. This indicates that KCl concentration has no effect on the particle size, but has effect on the hydrodynamic size of TiO2QDs. The black TiO2QDs can be produced by the hydrogenation process of hydrogen ions during electrochemical process. The obtained black TiO2QDs can be further explored as an electron‐transporting layer for a perovskite solar cell application. The black titanium dioxide (TiO2) quantum dots (QDs) are successfully grown by a solution‐based electrochemical process. The black TiO2QDs show broader absorption over a visible range (400–700 nm). Transmission electron microscopy indicates that average size of the black TiO2QDs is 4.5 nm. The obtained black TiO2QDs can be further explored as an electron‐transporting layer for perovskite solar cell application.