Host Crystal Research Articles

Metal-Organic Frameworks@Calcite Composite Crystals.

The direct incorporation of guest crystals into another type of host crystals during the formation of the latter is technically challenging due to the large difference in surface energy for different crystalline components. Nevertheless, we herein demonstrate that metal-organic frameworks (MOFs, UiO-66-NH2 as a model guest crystal) after postsynthetic modification with poly(methacrylic acid) can be efficiently incorporated into calcite single crystals, forming a unique composite structure where the MOF crystals are uniformly distributed throughout the whole calcite host crystals. Remarkably, such MOF@calcite composite crystals exhibit superior performance in fluoride removal compared with the MOF or calcite alone. Moreover, this incorporation strategy is general as it can be extended to other guest particles. In principle, this study opens up a versatile avenue for the rational design and preparation of a wide range of hybrid functional materials with controllable compositions and enhanced physicochemical properties.

Optical characterisation of dyed liquid crystal cells

ABSTRACT The guest-host liquid crystal display, first proposed in 1968, relies on controlling the orientation of dichroic dyes dissolved in a nematic liquid crystal host. Controlling the orientation of the liquid crystal and of the dissolved dye with an electric field allows control of the transmittance of the cell. Knowing the dielectric properties at optical frequencies of the dye and liquid crystal mixtures is crucial for the optimal design of guest-host liquid crystal devices. In this work, the dielectric functions of various layers in liquid crystal cells are described by models obeying the Kramers-Kronig relations: the Sellmeier equation for transparent layers and the causal Gaussian oscillator model for absorbing layers. We propose a systematic way to accurately model the dielectric response of each layer by minimising the sum of squared differences between the measured transmittance spectrum of a guest-host cell in the near-UV/vis range and the prediction of the transmittance of the modelled multilayer structure. By measuring the transmittance for incident light polarised parallel and perpendicular to the nematic director allows us to separately characterise the two principal dielectric functions of the uniaxial sample. Our results show that the causal Gaussian oscillator model can accurately characterise the dielectric functions of dyes in liquid crystals.

Programming and Dynamic Control of the Circular Polarization of Luminescence from an Achiral Fluorescent Dye in a Liquid Crystal Host by Molecular Motors

AbstractCircular polarized light is utilized in communication and display technologies and a major challenge is to develop systems that can be switched between left and right circular polarized luminescence with high degrees of polarization and enable multiple addressable stable states. Luminescent dyes in Liquid Crystal (LC) cholesteric phases are attractive systems to generate, amplify and modulate circularly polarized luminescence (CPL). In the present study, we employ light‐driven molecular motors as photo‐controlled chiral dopants in LCs to switch the handedness of the LC and the circular polarization of luminescence from an achiral dye embedded in the mesogenic material. Tuning of the color of the CPL and the retention time of the photoprogrammed helicity is demonstrated making use of a variety of motors and dyes. The flexibility offered by the design based on inherently chiral unidirectional rotary motors provides full control over CPL non‐invasively by light, opening possibilities for pixilated displays with externally addressable polarization.

Programming and Dynamic Control of the Circular Polarization of Luminescence from an Achiral Fluorescent Dye in a Liquid Crystal Host by Molecular Motors.

Circular polarized light is utilized in communication and display technologies and a major challenge is to develop systems that can be switched between left and right circular polarized luminescence with high degrees of polarization and enable multiple addressable stable states. Luminescent dyes in Liquid Crystal (LC) cholesteric phases are attractive systems to generate, amplify and modulate circularly polarized luminescence (CPL). In the present study, we employ light-driven molecular motors as photo-controlled chiral dopants in LCs to switch the handedness of the LC and the circular polarization of luminescence from an achiral dye embedded in the mesogenic material. Tuning of the color of the CPL and the retention time of the photoprogrammed helicity is demonstrated making use of a variety of motors and dyes. The flexibility offered by the design based on inherently chiral unidirectional rotary motors provides full control over CPL non-invasively by light, opening possibilities for pixilated displays with externally addressable polarization.

Effect of Sn concentration on the structural, morphological and thermoelectric transport properties of zinc Stannates thin films

This study aimed to set suitable Tin dopant concentration in ZnO based thin films to get optimal structural, morphological and thermoelectric properties. The samples under investigation were prepared by thermal evaporation technique using stoichiometric ratios of Zn and Sn powders. X-ray diffractograms showed that all grown samples are fully c-axis oriented but increasing Sn concentration caused a blue shift in XRD peak position. Raman spectrum of ZTO nanoparticles has confirmed the perfect wurtzite structure having an intense E2 mode. It was further showed that with increasing crystallite size, the frequency of E2 (highest peak) phonon mode decreases whereas its line width increases. The Seebeck coefficient has maximum value (800 μV/K) for un-doped sample while the value of electrical conductivity (5.2 S/cm) has maximum value for sample having Sn concentration 4%. This behavior of thermoelectric properties can be understood by the fact that Sn doping concentration increases the free carrier concentration in the host crystal of ZnO which resulted in the reduction of Seebeck coefficient and enhancement of electrical conductivity. This argument was further highlighted by the SEM measurements.

Transparent Josephson junctions in higher-order topological insulator WTe2 via Pd diffusion

Highly transparent superconducting contacts to a topological insulator (TI) remain a persistent challenge on the route to engineer topological superconductivity. Recently, the higher-order TI ${\mathrm{WTe}}_{2}$ was shown to turn superconducting when placed on palladium (Pd) bottom contacts, demonstrating a promising material system in pursuing this goal. Here, we report the diffusion of Pd into ${\mathrm{WTe}}_{2}$ and the formation of superconducting ${\mathrm{PdTe}}_{x}$ as the origin of observed superconductivity. We find an atomically sharp interface in the direction vertical to the van der Waals layers between the diffusion crystal and its host crystal, forming state-of-the-art superconducting contacts to a TI. The diffusion is discovered to be nonuniform along the width of the ${\mathrm{WTe}}_{2}$ crystal, with a greater extent along the edges compared to the bulk. The potential of this contacting method is highlighted in transport measurements on Josephson junctions by employing external superconducting leads.

Quartz Vein Formation and Deformation during Porphyry Cu Deposit Formation: A Microstructural and Geochemical Analysis of the Butte, Montana, Ore Deposit

Abstract Hydrothermal quartz veins from the Butte deposit display euhedral and mottled cathodoluminescent (CL) textures that reflect the growth and deformation history of quartz crystals. A CL-euhedral texture consists of oscillatory dark-light zonations that record primary precipitation from an aqueous fluid. The origin of a CL-mottled texture, which consists of irregularly distributed dark and light portions, is less clear. Previous work showed that in some veins, CL-euhedral and CL-mottled crystals coexist, but the processes leading to their formation and coexistence were unknown. We find that CL-mottled crystals occur predominantly along the wall rock fracture surface and in vein centers and that CL-euhedral cockscomb quartz protrudes from the mottled layers along the wall rock. We infer that the mottled crystals formed by strain-induced recrystallization that was preferentially accommodated by the rheologically weaker layers of noncockscomb quartz because cockscomb crystals are in hard glide orientations relative to adjacent noncockscomb layers. During strain, crystals in noncockscomb layers that are not initially susceptible to slip can rotate in their deforming matrix until they deform plastically. Some of the CL-mottled crystals exhibit a relict CL-euhedral texture (“ghost bands”) whereby bright bands have been blurred and deformed owing to Ti redistribution facilitated by grain boundary migration. The edges of some CL-euhedral crystals become CL-mottled by localized grain boundary migration along adjacent crystals that do not align perfectly. Throughout the veins, CL-mottled crystals are randomly oriented, indicating that small deviatoric stresses were sufficient to drive recrystallization and mobilization of trace elements. Ti concentrations in CL-mottled crystals (23-47 ppm Ti; mean of 31 ppm) overlap those of CL-euhedral dark growth bands (16-40 ppm Ti; mean of 25 ppm Ti) in neighboring CL-euhedral crystals. Average Ti concentrations in CL-mottled quartz and CL-euhedral dark growth bands correspond to temperature estimates of 600°C (31 ppm Ti; CL-mottled) and 619°C (25 ppm Ti; dark bands), which are in good agreement with previous quartz precipitation temperature estimates based on independent thermobarometers. We conclude that recrystallization resets CL-mottled Ti concentrations close to the equilibrium value for the conditions of deformation and that CL-dark growth bands record near-equilibrium Ti concentrations. Recognition of widespread quartz recrystallization in porphyry Cu deposits underscores the significant role that strain plays in deposit formation. Individual veins host crystals that preserve conditions of primary growth and other crystals that preserve conditions of deformation and thermal overprint. Textural information is key to accurately interpreting trace element data and identifying different stages of vein formation. Our suggestion that CL-dark bands are the best candidates for near-equilibrium growth will aid the interpretation of trace element zoning in other hydrothermal systems.

Er-doped anatase TiO2 thin films on LaAlO3 (001) for quantum interconnects (QuICs)

Rare-earth ions (REIs) doped into solid-state crystal hosts offer an attractive platform for realizing quantum interconnects that can function as quantum memories and quantum repeaters. The 4f valence electrons of REIs are shielded by 5s and 5p electrons and undergo highly coherent transitions even when embedded in host crystals. In particular, Er3+ has an optical transition in the telecom band that is suitable for low-loss communication. Recently, REIs in thin film systems have gained interest due to potential advantages in providing a flexible host crystal environment, enabling scalable on-chip integration with other quantum devices. Here, we investigate the structural and optical properties of Er-doped anatase TiO2 thin films on LaAlO3 (001) substrates. By choosing a system with minimal lattice mismatch and adjusting Er-dopant concentration, we achieve optical inhomogeneous linewidths of 5 GHz at 4.5 K. We show that 9 nm-thick buffer and capping layers can reduce the linewidth by more than 40%, suggesting a pathway to further narrowing linewidths in this system. We also identify that Er3+ ions mainly incorporate into substitutional Ti4+ sites with non-polar D2d symmetry, which makes Er dopants insensitive to the first order to local electric fields from impurities and is desirable for coherence properties of Er3+ spins.

Band Gap Calculations for Thorium‐Doped LiCAF

AbstractThe large band gap insulator LiCaAlF6 (LiCAF) has been proposed as a possible host crystal for future realizations of a solid‐state based thorium‐229 nuclear clock, due to its excellent optical transmission in the vacuum ultraviolet range. To enable direct optical manipulation of the thorium isomeric state, the band gap has to remain larger than the nuclear excitation energy upon crystal doping. Here, a systematic search for possible charge compensation mechanisms, defect locations, and the emergence of other compounds, using density functional theory, is presented. Out of 535 optimized structures, the energetically most favorable arrangement is with an estimated band gap of 11.4 eV. Evaluating relevant uncertainties of the used methods suggests that the doped material remains transparent at the 229Th isomer energy for all investigated configurations.

Structural, luminescent, and morphological properties of Eu3+-doped NaTaO3 thin films grown by magnetron sputtering

Radio-frequency (RF)-sputtered Eu3+-doped NaTaO3 thin films were grown at different deposition temperatures. The X-ray diffraction patterns revealed that all thin films contained two mixed phases of NaTaO3 and Na2Ta8O21. The photoluminescence spectra of the thin films consisted of a strong orange emission (592 nm) and two weak red bands (616 nm and 689 nm), suggesting that more Eu3+ ions in the NaTaO3 host crystal were located at inversion symmetry sites. The maximum intensities of all emission peaks were achieved for the sample grown at 100 °C, in which the gravel-shaped crystallites evolved with a band gap energy of 4.61 eV, chromaticity coordinates of (0.554, 0.434), and average transmittance of 92.4%. These results indicate that the photoluminescence intensity, band gap energy, and color tunability can be achieved for RF-sputtered Eu3+-doped NaTaO3 thin films by varying the growth temperature.

CRYSTAL GROWTH IN SOLUTION AND CHARACTERIZATION OF RUBIDIUM SULFATE SINGLE CRYSTALS DOPED WITH L-LEUCINE

Rubidium sulfate crystal is an inorganic material and it is doped with an organic material viz. L-leucine to improve the various properties of the host crystal. L-leucine doped rubidium sulfate (LLRS) crystals have been grown by solution method. LLRS crystals have been harvested after the growth period of 30 days. The grown LLRS crystal is observed to be crystallizing in orthorhombic structure by single crystal XRD studies. Mechanical studies were carried out to find the mechanical strength and other parameters. Dielectric studies of L-leucine doped rubidium sulfate crystals were carried out to evaluate dielectric constant, dielectric loss and activation energy. UV-visible-NIR spectral studies were done in the wavelength range 200-1100 nm and linear optical properties like transmittance, absorption coefficient and extinction coefficient of samples have been evaluated. Second order Non Linear Optical (NLO) studies of the grown crystal of LLRS were carried out by Kurtz-Perry technique. The fundamental absorption was noted at 280 nm and at 278 nm for undoped and L-leucine doped rubidium sulphate crystals respectively. The optical band gap of LLRS crystal was found to be slightly more than that of undoped rubidium sulphate crystal. The SHG efficiency of LLRS crystal is observed to be 0.61 times that of the reference KDP sample.

Tuning the Magnetization of Manganese (II) Carbonate by Intracrystalline Amino Acids.

Incorporation of organic molecules into the lattice of inorganic crystalline hosts is a common phenomenon in biomineralization and is shown to alter various properties of the crystalline host. Taking this phenomenon as a source of inspiration, it is shown herein that incorporation of specific single amino acids into the lattice of manganese (II) carbonate strongly alters its inherent magnetic properties. At room temperature, the magnetic susceptibility of the amino-acid-incorporating paramagnetic MnCO3 decreases, following a simple rule of mixtures. When cooled below the Néel temperature, however, the opposite trend is observed, namely an increase in magnetic susceptibility measured in a high magnetic field. Such an increase, accompanied by a drastic change in the Néel phase transformation temperature, results from a decrease in MnCO3 orbital overlapping and the weakening of superexchange interactions. It may be that this is the first time that the magnetic properties of a host crystal are tuned via the incorporation of amino acids.

Synthesis, photoluminescence, and up-conversion luminescence properties of YTiTaO6:Er3+/Yb3+

The relationship between the factors (i.e. the concentrations of Yb3+ and Er3+ and heating temperature in air) and the properties of photoluminescence (PL) and up-conversion luminescence of YTiTaO6:Er3+/Yb3+ whose crystalline phase depended on heating temperature in air was examined using samples synthesized hydrothermally. The intense green emission (: 2H11/2,4S3/2→4I15/2 transitions of Er3+) was obtained by the excitation at 288 ​nm using the indirect energy transfer from the YTiTaO6 host crystal, which was about 1.8 times stronger than that obtained by the direct excitation at 380 ​nm via the f-f transition (: 4I15/2→4G11/2) of Er3+. Aeschynite phase exhibited intermediate luminescence property. The up-conversion emission intensity increased with increasing heating temperature and became the maximum at x ​= ​0.10 and y ​= ​0.20 with euxenite phase, although the co-presence of Yb3+ gave negative effect on the PL intensity of ErxYbyY1-x-yTiTaO6. As heating temperature rose to 1300–1400 ​°C the intensity of the red up-conversion emission (: 4F9/2→4I15/2 transition) became greater than that of the green emission (: 4S3/2→4I15/2 transition), accordingly the position of the color chromaticity coordinates shifted slightly from green to yellow.

Effect of Halogens in Bis(haloaryloxyl)pyrazine Host Crystals on the Room Temperature Phosphorescence Properties of Bisbenzofuropyrazine Guest Luminophores

Several title host crystals including guest luminescent compounds exhibit apparent room temperature phosphorescence (RTP) along with fluorescence under atmospheric conditions. The lifetime of RTP is a marked function of the halogen atoms, decreasing in the order of Cl > Br > I, while the phosphorescence efficiency depends on the structural compatibility of the guests in the host crystals.

Optimizing Raman spectral collection for quartz and zircon crystals for elastic thermobarometry

Abstract Raman spectroscopy is widely used to identify mineral and fluid inclusions in host crystals, as well as to calculate pressure-temperature (P-T) conditions with mineral inclusion elastic thermobarometry, for example quartz-in-garnet barometry (QuiG) and zircon-in-garnet thermometry (ZiG). For thermobarometric applications, P-T precision and accuracy depend crucially on the reproducibility of Raman peak position measurements. In this study, we monitored long-term instrument stability and varied analytical parameters to quantify peak position reproducibility for Raman spectra from quartz and zircon inclusions and reference crystals. Our ultimate goal was to determine the reproducibility of calculated inclusion pressures (“Pinc”) and entrapment pressures (“Ptrap”) or temperatures (“Ttrap”) by quantifying diverse analytical errors, as well as to identify optimal measurement conditions and provide a baseline for interlaboratory comparisons. Most tests emphasized 442 nm (blue) and 532 nm (green) laser sources, although repeated analysis of a quartz inclusion in garnet additionally used a 632.8 nm (red) laser. Power density was varied from <1 to >100 mW and acquisition time from 3 to 270s. A correction is proposed to suppress interference on the ~206 cm–1 peak in quartz spectra by a broad nearby (~220 cm–1) peak in garnet spectra. Rapid peak drift up to 1 cm–1/h occurred after powering the laser source, followed by minimal drift (<0.2 cm–1/h) for several hours thereafter. However, abrupt shifts in peak positions as large as 2–3 cm–1 sometimes occurred within periods of minutes, commonly either positively or negatively correlated to changes in room temperature. An external Hg-emission line (fluorescent light) can be observed in spectra collected with the green laser and shows highly correlated but attenuated directional shifts compared to quartz and zircon peaks. Varying power density and acquisition time did not affect Raman peak positions of either quartz or zircon grains, possibly because power densities at the levels of inclusions were low. However, some zircon inclusions were damaged at higher power levels of the blue laser source, likely because of laser-induced heating. Using a combination of 1, 2, or 3 peak positions for the ~128, ~206, and ~464 cm–1 peaks in quartz to calculate Pinc and Ptrap showed that use of the blue laser source results in the most reproducible Ptrap values for all methods (0.59 to 0.68 GPa at an assumed temperature of 450 °C), with precisions for a single method as small as ±0.03 GPa (2σ). Using the green and red lasers, some methods of calculating Ptrap produce nearly identical estimates as the blue laser with similarly good precision (±0.02 GPa for green laser, ±0.03 GPa for red laser). However, using 1- and 2-peak methods to calculate Ptrap can yield values that range from 0.52 ± 0.06 to 0.93 ± 0.16 GPa for the green laser, and 0.53 ± 0.08 GPa to 1.00 ± 0.45 GPa for the red laser. Semiquantitative calculations for zircon, assuming a typical error of ±0.25 cm–1 in the position of the ~1008 cm–1 peak, imply reproducibility in temperature (at an assumed pressure) of approximately ±65 °C. For optimal applications to elastic thermobarometry, analysts should: (1) delay data collection approximately one hour after laser startup, or leave lasers on; (2) collect a Hg-emission line simultaneously with Raman spectra when using a green laser to correct for externally induced shifts in peak positions; (3) correct for garnet interference on the quartz 206 cm–1 peak; and either (4a) use a short wavelength (blue) laser for quartz and zircon crystals for P-T calculations, but use very low-laser power (<12 mW) to avoid overheating and damage or (4b) use either the intermediate wavelength (green; quartz and zircon) or long wavelength (red; zircon) laser for P-T calculations, but restrict calculations to specific methods. Implementation of our recommendations should optimize reproducibility for elastic geothermobarometry, especially QuiG barometry and ZiG thermometry.

Investigation on Ba2(Y1-x, Lux)5B5O17: y at.% Bi as a new type of N-UV excited high efficient blue phosphor for wLED

With its unique 6s2 outermost electronic structure, Bi3+ can emit blue, green and even red light, and Bi3+-activated luminescent materials for lighting are emerging. In this work, new blue-emitting Ba2(Y1-x, Lux)5B5O17: y at.% Bi (BYLBO: y at.% Bi) phosphors were synthesized by high temperature solid state method. By introducing Lu into the host lattice to substitute Y, the structural rigidity of the host crystal can be greatly strengthened and the phonon energy can be reduced. At the excitation of 370 nm, high efficiency and thermal stability blue light emission was achieved from Ba2Lu5B5O17: 1 at.% Bi (BYBO: 1 at.% Bi) phosphors. And it has a photoluminescence quantum yield (PLQY) of 78% and thermal quenching TQ150°C = 70%. Further, a bright wLED was fabricated by coating BLBO: 1 at.% Bi, commercial green and red phosphors on 370 nm n-UV chip, which chromaticity coordinate is (0.389, 0.378), correlated colour temperature (CCT) = 3395 K and the correlated color rendering index (CRI) = 91. These results not only provide a potential n-UV excited blue phosphor, but also shed a little light on how to design phosphors with strong thermal stability and high quantum efficiency.

Origin of Baseline Drift in Metal Oxide Gas Sensors: Effects of Bulk Equilibration

Metal oxide (MOX) gas sensors and gas sensor arrays are widely used to detect toxic, combustible, and corrosive gases and gas mixtures inside ambient air. Important but poorly researched effects counteracting reliable detection are the phenomena of sensor baseline drift and changes in gas response upon long-term operation of MOX gas sensors. In this paper, it is shown that baseline drift is not limited to materials with poor crystallinity, but that this phenomenon principally also occurs in materials with almost perfect crystalline order. Building on this result, a theoretical framework for the analysis of such phenomena is developed. This analysis indicates that sensor drift is caused by the slow annealing of quenched-in non-equilibrium oxygen-vacancy donors as MOX gas sensors are operated at moderate temperatures for prolonged periods of time. Most interestingly, our analysis predicts that sensor drift in n-type MOX materials can potentially be mitigated or even suppressed by doping with metal impurities with chemical valences higher than those of the core metal constituents of the host crystals.

Electronic Structure Calculation of Cr3+ and Fe3+ in Phosphor Host Materials Based on Relaxed Structures by Molecular Dynamics Simulation

The electronic structures of the luminescent center ions Cr3+ and Fe3+ in the deep red phosphors LiAl5O8:Cr3+, α-Al2O3:Cr3+, and γ-LiAlO2:Fe3+ were calculated by the DV-Xα method, in which the local distortion induced by the replacement of Al3+ sites in the host crystals by the luminescent center ions was reproduced by classical molecular dynamics (MD) simulation. The MD simulations based on classical dynamics allowed for the handling of more than 1000 atoms for the lattice relaxation calculations, which was advantageous to simulate situations in which a small number of foreign atoms (ions) were dispersed in the host lattice as in phosphors, even when typical periodic boundary conditions were applied. The relaxed lattices obtained after MD indicated that the coordination polyhedra around Cr3+ and Fe3+ expanded in accordance with the size difference between the luminescent center ions and Al3+ in the host crystals. The overall profiles of the partial density of states (p-DOSs) of the isolated Cr3+ and Fe3+ 3d orbitals were not significantly affected by the lattice relaxation, whereas the widths of the energy splitting of the 3d orbitals were reduced. The electronic structure calculations for Fe–Fe pairs in γ-LiAlO2 showed that the antiferromagnetic interactions with antiparallel electron spins between the Fe3+ ions were preferred, especially when the Fe–Fe pair was on the first-nearest neighboring cation sites.

Spectral broadening mechanism of Yb3+-doped cubic LuxSc2-xO3 sesquioxide crystals for ultrafast lasers

Over the past decades, Yb3+-doped cubic sesquioxide crystals have been considered as ideal gain materials for ultrafast laser generation, owing to their high thermal conductivity and adequate optical characteristics. The broadening of spectra by mixing host crystals to obtain short pulses has been extensively explored; however, few studies have examined the mechanism of the crystal field effect on spectral broadening. This paper describes the spectral broadening process caused by the combination of the discrete transition peaks induced by the crystal field effect and electron-phonon coupling widening based on Yb:LuxSc2-xO3 crystals. The energy level splitting induced by the crystal field effect not only determines the emission peak positions, but also broadens the emission spectra in the mixed host materials through the increasing spin-orbit coupling effect. Moreover, with the involvement of the electron-phonon coupling and the crystal field effect, the spectral broadening is much more obvious at room temperature. These results not only explain the spectral broadening mechanism of Yb3+-doped sesquioxides but also provide important insights for the improvement of new ultrafast laser materials.

Investigating the potential of AgZnO thin film composites for waste heat recovery using Seebeck data

In this paper, we have demonstrated the thermoelectric properties of Silver Zinc oxide (AgZnO) composite grown by thermal evaporation method. A mixture of Silver and Zinc powders with 1:4 ratio was evaporated on silicon substrate using a vacuum tube furnace. The grown composites were subjected to post growth annealing process at various temperatures ranging from 500 to 800 °C in a programmable muffle furnace. XRD data proved that the crystallinity of the annealed samples was improved because more and more oxygen atoms were able to fill the oxygen vacancy type defects in the host crystal of AgZnO. The observed structural behavior was also verified by Raman spectroscopy measurements. Seebeck measurements revealed a remarkable enhancement in the values of Seebeck coefficient (303–711 μV/°C) and electrical conductivity (17–176 S/cm) with annealing temperature. The high annealing temperature may cause an enhancement in the mobility of Ag atoms which resulted in the increase of Seebeck coefficient and electrical conductivity simultaneously.