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In this paper, the Ni–Fe–P ternary alloy coating was fabricated by electroless deposition and the process parameters of coating preparation were investigated in detail via response surface methodology. The optimal bath temperature and pH for Ni–Fe–P ternary alloy coatings were determined by the central composite design with two center points and the statistical model was established to identify the optimal process conditions for Ni–Fe–P ternary alloy coating. The micro-structure of Ni–Fe–P coatings was investigated by scanning electron microscope. The dispersive spectroscopy and X-ray diffraction were used to study the chemical composition of the coatings. The electrochemical impedance spectroscopy and the potential polarization techniques were used to research its corrosion resistance in 3.5 wt.% NaCl solution. The results show that the coating has the optimal corrosion resistance while the bath temperature was 85 °C and bath pH was 8.

A prominent issue is developing low-cost photocatalysts for water splitting hydrogen evolution. This work used a one-step microwave irradiation technique to make a copper ferrite incorporated graphitic carbon nitride (CuFe2O4/g-C3N4) nanocomposite for use as a visible-light reactive photocatalyst. XRD, SEM, TEM, Raman, UV, PL, and BET were used to analyze the structural, morphological, optical and elemental composition of the composite photocatalysts. CuFe2O4 was successfully incorporated in a g-C3N4 matrix in this composite, resulting in a CuFe2O4/g-C3N4 heterostructure that is substantially more efficient in photocatalytic H2 generation by water splitting under visible light. The photocatalytic activity of CuFe2O4/g-C3N4 composites is influenced by the CuFe2O4 loading mass. The 15-CuFe2O4/g-C3N4 composite, which includes 15% CuFe2O4, has a greater photocatalytic activity than the massive g-C3N4, with such a hydrogen evolution rate of 545 molh−1 g–1, which really is 9.1-fold that of the massive g-C3N4. This paper proposes a new way for improving semiconductor-based heterostructures for solar fuel generation efficiency.

The recent researches have shown that adding an appropriate amount of foreign reinforcements to lead-free solders can improve their wettablity, reduce their melting points, optimize their microstructure, and reinforce their mechanical properties. Moreover, it also inhibits the coarsening and growth of intermetallic compounds (IMC) and matrix microstructure under aging conditions such as high temperature aging or current stressing. However, there are still many limitations in the preparation and practical application of composite lead-free solders. By reviewing the existing research results, this paper summarizes the main problems in the preparation and applications of composite solder and analyzes the future research directions of this field.

MnZn ferrites and their magnetic, electrical, and optical properties make them highly suitable in a number of applications. These ferrites are used in electronic applications, magnetic fluids, and household appliances such as washing machines, refrigerators, and microwave ovens. This paper focuses on a hydrothermal method used to prepare a bayberry spherical manganese–zinc ferrite (Mn0.5Zn0.5Fe2O4), its surface was coated with dopamine (Mn0.5Zn0.5Fe2O4@PDA) and then carbonized to obtain the core–shell structure C-Mn0.5Zn0.5Fe2O4@PDA. Preliminary results show that carbon-coated manganese–zinc ferrite with saturation magnetic properties and coercivity increased from 99 emu and 66.01 Oe to 138 emu and 104.85 Oe, respectively. In addition, the carbonized Mn0.5Zn0.5Fe2O4@PDA (C-Mn0.5Zn0.5Fe2O4@PDA) exhibited favorable microwave absorbing performance with minimum reflection loss (RLmin) of − 17.56 dB and also revealed that the broadest effective absorption bandwidth (RLmin ≤ − 10 dB) 5.36 GHz (11.70–17.06 GHz) can be achieved at 2.0 mm.

The structural and optical properties of electrodeposited Cd1-xZnxS nanostructured thin films were investigated in the present paper for compositions of x = 0, 0.03, 0.06 and 0.09. X-ray diffraction patterns of the deposited thin films consisted of diffraction peaks related to cubic crystal lattice. The atomic compositional ratios were determined by performing energy dispersive spectroscopy measurements. Scanning electron microscopy images indicated that deposited thin films have nanostructured forms. Raman spectra of the Cd1-xZnxS thin films exhibited two vibrational modes associated with longitudinal optical mode and its first overtone. Transmission measurements were performed on the deposited thin films to get their band gap energies. It was seen from the analyses of absorption coefficient that band gap energy of Cd1-xZnxS thin films increases almost linearly from 2.40 to 2.51 eV as the composition was increased from x = 0 to x = 0.09.

Whether steel slag or printing and dyeing wastewater not only pollutes the environment but also occupies a lot of land. In this paper, steel slag is pretreated by acid leaching method at normal temperature and pressure to obtain chlorinated steel slag solution system. Then the system is electrolyzed by an electrochemical membrane method to obtain polymetallic carbonate precipitation. The electrolytic product is used as a precursor to obtain polymetallic oxide by calcination. Simulated dye wastewater was degraded with hydrogen peroxide as oxidant and polymetallic carbonate and its oxide as the photocatalysts, and their catalytic performances were compared. The degradation rates of Ca/Mg/Fe/Al/Mn/Ti/CO3 and Ca/Mg/Fe/Al/Mn/Ti/O catalysts were 3.05 times and 2.91 times higher than that of the blank catalyst, respectively. Ca/Mg/Fe/Al/Mn/Ti/O showed the best degradation efficiency and the removal rate of MB is as high as 99.56% after 80 min of illumination. Considering that the material is derived from low-cost solid steel scrap slag, it can not only treat wastewater but also solve the problems of harmful accumulation of solid waste, so the prepared materials are environmentally friendly and economic photocatalytic materials for printing and dyeing wastewater.

In this paper, a co-doped cubic phase submicron particles Ba2LaF7:Yb3+/Ln3+ (Ln = Er3+,Ho3+) up-conversion material were successfully synthesized by hydrothermal method. By adjusting PH, time, temperature, and the amount of sodium citrate during the preparation process, it was possible to analyze and obtain the phase structure, morphology, and up-conversion luminescence characteristics of the particles. Furthermore, the influence of doping concentration on the up-conversion luminescence characteristics was studied using X-ray diffractometer (XRD), scanning electron microscopy (SEM), fluorescence spectroscopy, and other characterization methods. The test results show that, under the conditions of pH = 9 and NaBF4 as the fluorine source, Ba2LaF7:Yb3+/Ln3+ (Ln = Er3+,Ho3+) spherical particles have an average size of 240 nm. Under the excitation of a 980 nm laser-diode (LD) laser, it was found that the material spectrum is mainly composed of strong green and weak red light. When Yb3+ and Er3+ doping concentrations are 18% and 2.5%, Yb3+ and Ho3+ doping concentrations are 18% and 3.5%, respectively, the up-conversion transmittance is the highest. Finally, the possible causes of the fluorescence decay curve of Ba2LaF7:Yb3+/Ln3+ (Ln = Er3+,Ho3+) up-conversion materials were investigated.

This paper aims to investigate the influence of composite flux on the interfacial reaction, wettability, and shear strength evolution of Sn-3.0Ag-0.5Cu (SAC305) solder joint; the ultrasonic vibration (USV) was performed to the solder joint during reflowing. Cu-modified graphene nanosheets (Cu-GNSs)-doped flux were prepared by chemical modification. It was found that the wettability of the solder was enhanced after the addition of Cu–GNSs, and the wetting angle was reduced up to 14.43%. While, the presence of Cu–GNSs could reduce the thickness of the intermetallic compound (IMC) layer and the size of IMC grain within the solder joint by 4.15% and 3.19%, respectively. Interestingly, the solder joint was prepared with 0.1 wt% Cu–GNSs-doped flux which had the optimal effect on enhancing the wettability of the solder and inhibiting the growth of the IMC layer. The application of USV during reflow could enhance the wettability of the solder and decrease the thickness and grain size of IMC within the solder joint. Shear test results stated that the employment of Cu–GNSs and USV made the shear strength of Cu/SAC305/Cu solder joint enhanced by up to 9.34% and 9.76%, respectively. Furthermore, as the content of Cu–GNSs doped in the flux increased, the fracture type of solder joints without USV treatment gradually changed from the ductile–brittle mixed type to the ductile type, whereas, the fracture type of all the solder joints-relayed USV treatment was the ductile type.

This review paper summarizes early Mossbauer and DTA studies of different oxide glasses containing small amounts of iron (III) or tin (IV) as the probe. A lot of valuable information of the atomic level has been obtained about the role of nonbridging oxygen (NBO), network former (NWF), network modifier (NWM), local network structure, glass transition, structural relaxation, crystallization, etc. Introduction of alkali oxide into iron (III)-containing oxide glass causes a marked decrease in glass transition temperature (Tg) amounting to 100 °C and a concordant decrease in quadrupole splitting (Δ) of FeIII, which reflects decreased distortion of NWF–oxygen polyhedra and formation of NBO. By contrast, introduction of non-alkali oxide into oxide glass causes an increase in Tg amounting to more than 100 °C and a concordant increase in Δ, reflecting increased distortion of NWF–oxygen polyhedra in highly cross-linked network. These experimental results led to a discovery of “Tg-Δ rule”, which was consistent with the “conformer model” proposed for polymers by Matsuoka and Quan. Debye temperatures (θD) obtained by low-temperature Mossbauer measurements proved to be useful to determine short- and long-range structures of glass and glass ceramics. Isothermal annealing of vanadate glasses at temperatures higher than Tg or crystallization temperature (Tc) causes a “tunable” decrease in DC-resistivity from the order of MΩ cm to Ω cm. Introduction of metal oxide with a narrow bandgap (Eg) is highly effective to increase the conductivity after the annealing. It was proved that “structural relaxation” of NWF–oxygen polyhedra and resultant decrease in the activation energy (Ea) for conduction are responsible for the improved conductivity. Heat treatment of IR-transmitting aluminate, gallate, and tellurite glasses at temperatures higher than Tg or Tc revealed that crystallization was triggered by the cleavage of NWF–oxygen bonds. These findings will contribute to the development of functional glass and glass ceramics such as smart glass and eco-friendly glass.

The combination of low dielectric constant (er) and a high-quality factor (Q × f) in MgO ceramics makes them attractive for 5G applications. However, the large negative temperature coefficient of resonance frequency (τf) impedes these applications. In this paper, the composite ceramics of MgO–xMTiO3 (M = Ca, Sr; x = 0, 2.5, 5, 7.5, 10 wt%) with the addition of 4 mol% LiF as a sintering aid were fabricated by the traditional solid-state reaction method. The coexistence both MgO and MT phases can be observed in XRD and SEM in the 4 mol% LiF–MgO–wt%MTiO3 systems under the high-temperature sintering process. With the addition of MT, the grain size of MgO decreased, the er value improved with τf value gradually increasing from negative to positive value. Optimized microwave dielectric properties were achieved for 4 mol%LiF–MgO–10wt%SrTiO3 ceramics sintered at 1300 °C for 6 h, yielding er = 11.2, Q × f = 46, 815 GHz, and τf = + 3.51 ppm/°C. Based on it, a prototype of microstrip patch antenna was designed and fabricated with a center frequency at 5.64 GHz for 5G–Sub6GHz communication applications.

This paper presents the results of a study of the structural, optical, and photocatalytic properties of ceramics based on ATiO3 titanates, A = Ca, Sr, Ba. Using the method of X-ray phase analysis, it was found that in the case of ceramics obtained from a mixture of BaCO3 and TiO2 after annealing, the structure is a mixture of two phases, rhombohedral BaTiO3 and impurity orthorhombic BaTi4O9. In the case of ceramics obtained from a mixture of CaCO3 and TiO2, the structure is a mixture of two phases of the orthorhombic phase and rutile TiO2. In the case of ceramics obtained from a mixture of SrCO3 and TiO2, the structure is a mixture of two phases of the SrTiO3 orthorhombic phase and the Ti2O5 orthorhombic phase. At the same time, all synthesized ceramics have a high crystallinity degree and order of the crystal structure. An analysis of the optical properties showed that the main changes are associated with the difference in the band gap, which is due to the presence of different phases in the structure of ceramics. Based on the results of photocatalytic reactions, the order of photocatalytic activity of the synthesized ceramics was determined: SrTO3/T2O5 > CaTO3/TO2 > BaTO3.

This paper reviews the use of graphene, reduced graphene oxide (rGO) and their modification as cathode for dye-sensitized solar cell (DSSC). Graphene and rGO can be modified via several ways, namely, doping, composing and coating with other materials in order to enhance their electrical property and catalytic activity when applied in DSSC. The composite structure of graphene and rGO with other class of materials such as metal oxide, metal sulfide, alloy and conducting polymers can be formed. Metal and non-metal can be doped into graphene and rGO. Other types of material can also be coated on graphene and rGO to modify their electrical property and catalytic activity. This review highlights the performance of the device in term of power conversion efficiency (PCE) employing the modified graphene and rGO and the electrochemical impedance spectroscopy (EIS) parameters that support the PCE such as charge transfer resistance (Rct), cathodic current density (J) and incident-photon conversion efficiency (IPCE). This review also highlights the future prospects of modified graphene and rGO as cathode for DSSC.

The purpose of this paper is to describe a novel method for producing zinc oxide (ZnO). Within only 10 min of the synthesis procedure, ZnO nanoparticles were precipitated directly from a sodium zincate after partial neutralization with sulfuric acid. The entire synthesis process was carried out at room temperature. There were no additives or additional operations, such as calcination, required in the proposed method. XRD, FESEM, and BET techniques were used to characterize the product, and XRD confirmed the formation of crystalline ZnO devoid of other phases. Consideration of the height of XRD peaks revealed that ZnO crystallites grow preferentially along the c-axis. FESEM revealed particles with a diameter of 30–50 nm which was also confirmed by analysis of the broadening of XRD peaks. Nearly spherical particles were observed by the FESEM. These nanospheres were primarily adhered together to form platelets. Finally, the BET analysis revealed a substantial specific surface area of 20 m2 g− 1.

Tunnel field effect transistors (TFETs) have proved themselves as a better choice for the replacement of MOSFET due to provision of scalability and possibility of better realization of goal to achieve subthreshold swing less than 60 mV/decade. Challenge of lower ON current in conventional TFET has been overcome by a heterojunction double-gate (DG) TFET structure in which a low bandgap material, magnesium silicide (Mg2Si) is implemented as source region. There is dire need to determine the reliability of such device under various constraints to optimize them for low-power and high-speed applications. Therefore, in this paper, authors examine the device reliability by investigating the analog/RF performance of Mg2Si source heterojunction double-gate TFET (MSH-DG-TFET) under the influence of interface trap charge polarity and density. This reliability analysis is accomplished by including the effect of trap charges (both positive interface charges, i.e., donors and negative interface charges, i.e., acceptors) at Si/SiO2 interface. Presence of these trapped acceptor and donor charges at Si/SiO2 interface modifies the flat-band voltage which in turn alters the performance of the device. It is revealed that for positive trap charge density of 1 × 1012 cm−2, the leakage current or off-state current of MSH-DG-TFET drastically increases from an order of 10–18 to 10–14 A/µm, thus degrading the performance. Further, presence of negative trap charges at interface tends to enhance the flat-band voltage that translates to the higher gate bias to turn the device ON. Results reveal that impact of positive interface charges is more pernicious on the device performance as compared to the negative interface charges. Thus, MSH-DG-TFET is susceptible to the donor traps existing at Si/SiO2 in comparison with the acceptor traps. Studies carried out may prove to be very useful for future research work in suggesting better TFET structures comprising of Mg2Si as source.

This paper describes the realization and characterization of $${\text{La}}_{0.8}{\text{Pb}}_{0.1}{\text{Ca}}_{0.1}{\text{Fe}}_{1-x}{\text{Co}}_{x}{\text{O}}_{3}$$ gas-based sensors. $${\text{La}}_{0.8}{\text{Pb}}_{0.1}{\text{Ca}}_{0.1}{\text{Fe}}_{1-x}{\text{Co}}_{x}{\text{O}}_{3}$$ $$(0.00\le x\le 0.20)$$ thin films are prepared using the drop-coating method over a $${\text{Si}}/{\text{SiO}}_{2}$$ substrate with inter-digitated $${\text{Pt}}$$ -electrodes. The sensors, thus, produced exhibit a good sensitivity to ozone at low concentration. The substitution of iron atoms by cobalt ones increases the sensor responses “S,” from 1.716 for $$x = 0.00$$ to 6.584 to $$x = 0.20$$ for an ozone concentration equal to $$400\,{\text{ppb}}$$ . In addition, the substitution of iron by cobalt induces a decrease in the sensor-operating temperature from $$270\,^\circ{\text{C}}$$ for the parent compound $$(x = 0.00)$$ to $$170\,^\circ{\text{C}}$$ for $$x = 0.20$$ .

This paper reports the electrical transmission properties of single-crystal PbSe samples prepared via Bi-flux method based on a stoichiometric ratio of Pb:Se:Bi = 1:1: x (x = 2.5, 3, 3.5, 4). Results show that all samples adopt an NaCl structure with the space group $$Fm\overline{3 }m$$ , with no cracks or micropores; the Bi atom substitutes for Pb consistently. All samples prepared by this method demonstrate n-type conduction and carrier concentrations varying from 2.48 and 4.21 × 1018 cm−3, which far exceeds that of the polycrystalline sample. Transmission electron microscopy (TEM) and corresponding area electron diffraction (SAED) further verify that the prepared sample has a typical single-crystal structure. Electronic band structure calculations indicate that the band gap of Pb32Se32 is 0.43 eV. After replacing a Pb by Bi atoms, the band gap is invariable and a resonant energy level is introduced into the band gap, which enhances the Seebeck coefficient. The power factor of the sample x = 3.5 reaches 3.6 × 10−3 W m−1 K−2 at 550 K, which is approximately 50% higher than that of the polycrystalline sample (1.8 × 10−3 W m−1 K−2) and can be attributed to the introduction of resonant states in the energy band for Bi replacing Pb.

SnBi lead-free solder is widely applied in the field of low-temperature soldering due to its excellent creep resistance, relatively low melting point (139 °C) and cost. However, the frangibility and poor ductility of the SnBi low-temperature solder limits its application in the field of electronic packaging. In this paper, the research progress and development direction of SnBi low-temperature lead-free solder are discussed. To promote the application of SnBi solder, the melting characteristics, wettability, microstructure, tensile properties, shear properties, creep properties and interfacial reaction of SnBi solder are analyzed and introduced systematically. It provides an important reference of understanding the current development of SnBi solders.

Fe3O4, as a half-metallic ferrimagnetic material, is believed to be one of the most promising materials in spin transport for spintronics. However, fabricating stoichiometric Fe3O4 film is still challenging because the oxidation is hard to control for various preparing methods. In this paper, series of Fe3O4 thin films on Si (100) substrates are grown by sputtering from a Fe3O4 target without oxygen atmosphere at different growth temperature and then extra heat treatment in high vacuum. By combining X-ray diffractometer (XRD), Raman spectrum, X-ray photoelectron spectroscopy and X-ray magnetic circular dichroism, VSM analysis, we see that the structure and magnetic moment of Fe3O4 film are not only related with growth temperature during sputtering, but also refer to the temperature of post-heat treatments. When the growth temperature is lower than 300 °C, the film does not show any XRD diffraction peaks. When the growth temperature increases from 300 to 500 °C, the film shows the (111) texture of Fe3O4 film clearly. However, the other XRD diffraction peaks are observed after post-heat treatment. The saturation magnetization increases with growth temperature and the largest saturation magnetization is 473 emu/cm3 for growth temperature of 450 °C and extra heat treatment, which is close to bulk Fe3O4. Our results suggest that a selectable method can be used to fabricate high magnetic moment of Fe3O4 thin film.

In the present prospective study, a variety of novel rare-earth Dy3+ singly activated Sr6Al4Y2O15 nanoscaled materials were fabricated through ecologically-sound as well as low-temperature facilitated urea-fueled combustion methodology. Monoclinic crystalline phase was recognized via the Rietveld analysis of X-ray powder diffraction (XRPD)-patterns. The metal–oxygen bonding pertaining in the studied sample was traced by the Fourier-transform infra-red (FT-IR) measurements. Energy dispersive spectroscopic (EDS) technology was used for the stoichiometric element distribution studies onto the present materials. The photoluminescent spectra (PL) recorded for fabricated powders, were primarily composed of two major bands viz. golden and bluish band centered at 579 and 485 nm, in the spectral regime. Luminance performance of present luminous materials was maximal at Dy3+ ion-content of x = 0.05; at which fluorescent decay-time (= 0.6701 ± 0.0056 ms), chromatic coordinates (x = 0.2865, y = 0.3312) and correlated color-temperature (CCT) value of 8089 K were determined. Quantum efficiency as well as color-purity of the Sr6Al4Y1.90Dy0.10O15 powders were obtained as 90.46% and 19.86 × 10–2, respectively. Attenuation of luminescence via exchange-kind inter-relations amidst Dy3+ ions, was assayed through Inokuti–Hirayama (I–H) model as well as Dexter’s formalization. Aforementioned outcomes, thereby, recommend the potential materialization of as-fabricated powder materials for near ultra-violet-stimulated white light-emanating diodes, luminance sensors, medical-diagnostics, biochemical probes and laser industry. Moreover, this research paper would provide a reference to conduct research into new such white-emanating aluminate-based phosphor materials.

Exploring polymer composites with a high dielectric constant (e′) and breakdown strength (Eb), low dissipation factor (tanδ), as well as a high thermal conductivity (TC) is of crucially important thanks to their potential applications in modern electronics. Herein, in this paper, two kinds of core–shell-structured Si particles, i.e., Si@SiO2, Si@SiO2@PS, were prepared by high temperature oxidation and polystyrene (PS) coating and incorporated into PVDF (poly(vinylidene fluoride)). The results indicate that both the fillers’ kinds and loading have obvious influences on dielectric and thermal properties of the composites. The SiO2 interlayer between the Si and PVDF matrix remarkably suppresses the loss and reduces leakage conductivity, whereas encapsulation of Si@SiO2 with a PS shell further inhibits the loss and conductivity, and the organic PS interlayer enhances the interfacial compatibility and promotes the fillers’ homogeneous dispersion in PVDF, therefore improving the Eb of the composites. More importantly, the PVDF composites with 50 wt.% of Si@SiO2@PS show good comprehensive performances: e′ of 66.6 but tanδ of 0.04 at 100 Hz, Eb of 2.48 kV/mm as well as a high TC of 1.0 W/m K. The prepared Si@SiO2@PS/PVDF composites show promising potential applications in microelectronics and electrical industries.

This paper investigates a novel electrochemical enzyme-free glucose sensor based on bimetallic PtNi materials. Pt and Ni layer were sputtered on the substrate and then annealed to form bimetallic PtNi materials, which served as sensitive materials for glucose detection. The effect of annealing temperature on the performance of enzyme-free glucose sensors had been studied deeply. Using micro-electromechanical systems (MEMS) technology, a monolithic enzyme-free glucose sensor was fabricated, which integrated with working electrode (WE) and counter electrode (CE) on a chip. The electrochemical results demonstrate that the device exhibits outstanding sensitivity and selectivity for glucose detection, achieving a maximal sensitivity of 1618.15 µA mM−1 cm−2 in the range of 0–10 mM with a low detection limit of 8.76 µM. The sensor also shows its practical application for glucose detection in human blood serum. Due to its performance and fabrication process, the enzyme-free glucose sensor is therefore well suited for glucose detection and manufacture together with other integrated circuits on a single silicon wafer, which shows potentials in implantable microelectronic systems.

In this paper, (Co-TeO2) nanostructures were synthesized using the microwave-assisted method for the fabrication of (PVP:Co-TeO2) as an organic interlayer (OI) at Al/p-Si interface. Structural and optical properties of nanostructures were investigated through XRD, SEM, EDX, and UV-Vis techniques. The interface states (N-ss) energy dependence diagram were also obtained from the voltage-dependent ideality factor (n) and barrier height (BH). Experimental results confirmed that the OI improved the performance of MS structure in respect of low N-ss, R-s, n, and high rectification rate (RR). Both the forward- and reverse-bias conduction mechanisms such as ohmic, space/trap-charge-limited current (SCLC/TCLC), and Poole-Frenkel/Schottky emission (PFE/SE), respectively, were implemented. Additionally, basic dielectric parameters of two structures were investigated in detail using impedance-frequency (Z-f) measurements in a wide frequency range (0.1-1000 kHz) and they were a strong function of frequency because of the existence of N-ss, surface polarization, and interlayer.

The extrusion-casting process can realize large-area and continuous preparation of polymer-based films. In this paper, five different types of polyvinylidene fluoride (PVDF)-based piezoelectric films: PVDF, PVDF/PZT, PVDF/PZT@105, PVDF/PZT/BNNS and PVDF/PZT@105/BNNS were prepared by the extrusion-casting process. The mechanical, dielectric, thermal conductivity and piezoelectric properties were studied. It is found that PZT particles can well improve the dielectric performance and also the mechanical stability under variable temperature conditions. PZT powders modified by titanate coupling reagent (UP-105) can further improve the performance of the PVDF/PZT@105 films by improving the combination and dispersion of organic and inorganic phases. The addition of boron nitride nanosheets (BNNS) can improve the thermal conductivity of the films and the breakdown strength. The piezoelectric coefficient (d33) of PVDF/PZT@105/BNNS composite film can reach 21pC/N, compared with the neat PVDF film (4pC/N) and PZT/PVDF (9pC/N) film realizing great improvement.

This paper reported a research of the sinterability, microstructures, and microwave dielectric properties of Ba(Mg1/3Ta2/3)O3 (BMT) ceramics with different amounts of B2O3 additive. The results showed that B2O3 addition had an obvious effect on reducing the densification sintering temperature without detriment of the dielectric properties. Appropriate B2O3 addition could effectively lower the densification sintering temperature of BMT ceramics from 1650 to 1250 °C and achieved superior microwave dielectric properties. However, surplus B2O3 content addition caused abnormal grain growth and therefore deteriorated the densification and microwave dielectric properties of the BMT ceramics. Finally, BMT ceramics with 3 wt% B2O3 possessed superior microwave dielectric properties: er = 24.2, Q × f = 92,600 GHz (f = 8 GHz), and τf = 3.5 ppm/°C were achieved when sintered at 1250 °C.

Nanostructured transition metal oxides are promising anode materials for lithium-ion batteries. Nevertheless, the problem of high volume expansion rate limits its further application. In this paper, we present a 3D hierarchical SnO2 hollow nanotubes material by calcining C@SnS2 materials in the air. This structure combines the advantages of both the hollow nanotubes and the outer staggered nanosheets structure, in which the hollow nanotube can provide more lithium ion transport channels, the space between the tubes can buffer the volume change, and the staggering nanosheets structure can effectively improve the relative specific surface area of the material and improve the storage capacity. As a result, the SnO2 hollow nanotubes anode exhibits the highly reversible capacity of 1079 mAh g−1 at a current density of 100 mA g−1, while the reversible specific capacity of 770 mAh g−1 was obtained after 100 cycles. The research results obtained in this work provide a feasible strategy for synthetic nanoscale transition metal oxide as high-performance lithium anode material.

In order to develop sustainable and renewable energy sources, novel approaches to design noble metal-free efficient electrocatalysts such as carbon and metal dichalcogenides nanostructures are being investigated for hydrogen evolution reaction (HER). In the present work, we successfully synthesize iron nanoparticles (Fe–GT) via facile green approach without using any surfactant and for the first time, green-synthesized iron nanoparticles are utilized as catalysts for production of multiwalled carbon nanotubes (MWCNTs). The synthesized MWCNTs (GT) were characterized using SEM, TEM, XRD and Raman spectroscopy techniques. The MWCNTs (GT)-coated conducting carbon paper electrode was applied as non-precious metal electrocatalyst for HER. The MWCNTs (GT) electrode demonstrates improved electrochemical activity towards HER with a smaller value of Tafel slope ~ 105 mV dec− 1 and overpotential (η10) ~ 192 mV, which is quite comparable to other reported metal-free HER catalyst. We also designed an indigenous electrochemical cell and showed the hydrogen production and collection using MWCNTs (GT) as cathode.

Self-assembled InAs/GaAs quantum dots (QD) are extensively studied for their potential application in optoelectronic devices. In this paper, we report the influence of QD growth rate on the optical properties of InAs/GaAs QDs under their exposure to a Nitrogen plasma. The samples under study are grown by molecular beam epitaxy and characterized by photoluminescence spectroscopy (PL). For capped unnitrided QDs, the increase in InAs growth rate is accompanied by an increase in PL emission energy and PL full width at half maximum (FWHM). Under nitridation, it was found that the incorporation of Nitrogen (N) strongly affected the QD emission and showed a significant redshift of the photoluminescence peak emission. In addition, PL FWHM decreases as the growth rate of InAs increases. The temperature dependence of the PL peak energy of the unnitrided and nitrided QDs exhibits a V shape associated to the carrier localization phenomenon induced by the spatially fluctuating potential. This behavior is confirmed by using the localized state ensemble (LSE) theoretical model. In addition, the results suggest that nitridation aims to reduce the size distribution of QDs and leads to their homogenization compared to the case of inhomogeneous distribution in the absence of Nitrogen. These results are a particularly promising method for realizing QD lasers, which require the use of low QD size and high density with minimal size dispersion.

Low-alkali borosilicate glasses are widely used in electronic packaging applications due to their low dielectric constant, low dielectric loss and excellent matching of thermal expansion coefficient to silicon. This paper presents information about structural, thermal and dielectric investigations of low-alkali borosilicate glass compositions for potential electronic packaging applications. Different bulk borosilicate glass samples were fabricated by conventional melting and quenching technique followed by powder processing. Total alkali oxide content in the composition was kept at 2–3 wt% to achieve high dielectric performance. The glass structure was investigated by Fourier transform infrared spectroscopy. X-ray diffraction analysis was employed to investigate crystallization behavior. Thermal properties were investigated by a heating microscope as well as a push-rod dilatometer. The dielectric properties were investigated by an impedance analyzer at room temperature. The results indicated that the glass structure connectivity has a significant effect on thermal and dielectric properties. Reduced glass structure connectivity due to the lower amount of tetrahedral BO4 units resulted in decreased bulk density, dielectric constant and characteristic temperatures as well as glass transition temperature (Tg). Sample D is a promising candidate for electronic packaging application due to its excellent matching of thermal expansion coefficient (3.3 ppm/°C) to Silicon, relatively low softening point (720 °C) and Tg (450 °C), low dielectric constant (4.07) and low dielectric loss (0.0029).

The insertion of an electron reflector is a suitable method to enhance the open‐circuit voltage (Voc) of copper indium gallium selenide (CIGS) solar cells. By the electron reflector, an electron barrier is formed at the conduction band, which can considerably reduce the recombination rate at the rear interface. In this paper, the copper zinc tin sulfide-selenide (Cu2ZnSn(S1−xSex)4) as an electron reflector is implemented on the thin‐film CIGS reference cell with a world record efficiency of 23.3%, then the properties of the proposed CIGS solar cell are numerically studied. The bandgap alignment at the Cu2ZnSn(S1−xSex)4/CIGS interface is adjusted by the selenium-to-sulfur ratio in the electron reflector layer. Simulation results show that an enhanced Voc was achieved in the CIGS solar cell with Cu2ZnSn(S1−xSex)4 (x

Quantum dots (QDs) attract extensive attention because of their excellent optoelectronic performance. However, few research has been done on the synthesis of core–shell QDs by one-step thermal injection. Here the CdSe/ZnS core–shell QDs were successfully synthesized by a one-step thermal injection method. The synthesis process of CdSe/ZnS core–shell QDs was investigated from two aspects of reaction time and oleic acid dosage. The results suggest that the reaction time and the dosage of oleic acid have important effects on the optical properties of CdSe/ZnS core–shell QDs. The action mechanism of oleic acid was also explained in this paper. Moreover, highly efficient green quantum dot light-emitting diodes (QLEDs) were fabricated with CdSe/ZnS core–shell QDs on ITO glass substrate by rotary coating method. The minimum starting voltage of 1.91 V and the maximum brightness of 12,057 cd m−2 were achieved in the QLEDs. This study is of great significance for the development of the synthesis of core–shell QDs by one-step thermal injection and QLEDs.

In recent years, the tunability of solid-state light sources has become an ideal feature for the illumination and exhibition industries. However, the ability of spectral and intensity tunability independently is still crucial. In this paper, an integrated OLED device, serving as a conceivable solvent to illuminant utilized in the tunable luminous scheme, is put forward as the intelligent color displays. The manufactured OLED device consists of a forward and an inverted sub-cell, which allows the demand of different materials for device structure compared to devices composed of the same structure, thus realizing the requirements of high-efficiency, high-brightness, and easy-fabrication. Then, the working mechanism of this organic electroluminescent device is discussed and utilized with AC electrical signals to address each emitter cell independently for adjusting the corresponding color temperature and intensity. The functional structure using forward and inverse integration with AC-driven can be integrated into commercial power systems for various lighting situations, thus bringing potential development of future intelligent displays.

This paper reports the effect of chromium’s substitution in magnetic oxides with perovskite structure La0.5Sm0.2Sr0.3Mn1-xCrxO3 (x = 0, 0.1, 0.15 and 0.2) compounds which have been produced with the glycine-nitrate process (GNP). The four compounds have an orthorhombic crystal structure with ‘Pnma’ space group. We note that they undergo a second-order paramagnetic-ferromagnetic (PM-FM) phase transition. Substitution manganese by chromium leads to a drop of the Curie temperature TC from 278 K (x = 0) to 205 K (x = 0.2). Their magnetocaloric effect has been evaluated by their magnetic entropy change $$\left(-\Delta {S}_{M}^{max}\right)$$ under a magnetic field change up to 5 T. All relative cooling power (RCP) suggests that these compounds are suitable candidates for magnetic refrigeration.

At present, screen printing is the most widely used technique in the printed electronics industry and the printed pattern can satisfy certain electronic application requirements. Ink development is the most important part of the printing process. In this paper, a new particle-free MOD ink (MOD = metal–organic-decomposition) was synthesized from silver malonate, diethanolamine (DEA) and ethylene glycol (EG). Silver malonate was the precursor of silver. DEA was the complexing agent that maked silver malonate soluble. EG acted not only as a solvent to regulate the rheological properties of the ink, but also as a reducing agent to reduce silver ions. The decomposition temperature was reduced from 210 °C to about 100 °C by the formation of silver-amine complex, thus the selection range of substrate could be broadened. The ink was spread on the polyimide (PI) substrate by screen printing. The silver film was formed after heat treatment at 150 °C for 1 h and its electrical conductivity can reach 1.0 × 104 S cm−1, which corresponded to one sixty-third of the theoretical conductivity of the bulk silver (6.3 × 105 S cm−1).

Transition metal sulfides have been extensively applied to the electrode materials of supercapacitors for its intrinsic high capacitance, low electronegativity, low cost, and outstanding conductivity. However, the common vulcanization processes for preparing electrode materials of transition metal sulfides are generally time-consuming (nearly 10–24 h) and inseparable from high-temperature heat treatment (nearly 200–400 °C). In this paper, we introduce a rapid room temperature process with direct sulfuration (4 h) of precursors without additional preheating treatment steps to prepare the nail-like Cu2S nanoarrays with a partial interconnected structure on copper foam (Cu2S/Cu). As the electrode of supercapacitors, the Cu2S/Cu reveals good capacitance performance (1219 F g−1 at 5 mA cm−2) and outstanding cycling stability (92% retained after 5000 cycles at 30 mA cm−2). These superior electrochemical performances may be mainly due to the fact that the nail-like Cu2S nanoarrays with a partial interconnected structure will provide efficient transport pathways for both electrons and ions along the longitudinal axis of the one-dimensional nanostructure.

This paper investigates the effect of grain size on the evolution and shear behavior of lead-free solder joints. The grain size of the solder is 2-11 μm, 5-15 μm, 15-25 μm, respectively. The interface structure of the solder joint and the microstructure of the inferred surface are analyzed. The void ratio of the flip-chip solder layer is tested. In order to study the change of shear strength and fracture surface, the solder/copper joint was subjected to isothermal aging treatment (1000 h) under the environment of relative humidity of 85 °C/85%. The results show that the smaller the solder crystal grains, the larger the surface area of the crystal grains per unit mass. Because of the action of the liquid bridge force, tin powder agglomeration is prone to occur, which leads to a high void rate of the solder layer. At this time, a higher activity flux is required to remove oxides. Highly active flux (NC559-TPF) was added and verified. When the grain size is 5-15 μm, the solder paste has the best soldering performance. After the filament is aged for 1000 h, the junction temperature is the lowest. Secondly, the blue light flux is the highest.

This paper has focused on investigating the structure, dielectric, and magnetic characteristic of Sn-ZnO nanopowder with Sn (x = 0%, 2%, 4%, and 6%) synthesized by the co-precipitation technique. Our objective was to obtain the material of low dielectric constant, high electrical conductivity, and magnetism. X-ray diffraction confirmed the Sn-ZnO nanoparticles have a ZnO-like hexagonal structure. It is found that the dielectric constant, dielectric loss, and a.c conductivity of doped nanoparticles were frequency-dependent. The dielectric constant of all the doped samples were increased by the increase in the Sn-doped concentration, while the decrease in frequency increased the dielectric constant and loss. Moreover, the a.c conductivity was increased by the increase in Sn concentration and frequency. Ferromagnetism was observed in ZnO doped with 4% and 6% Sn at room temperature. In addition, a robust magnetic hysteresis loop was observed for doped with 4% Sn to ZnO nanopowder at 300 K with coercive field (Hc) ~ 49 Oe and remnant magnetization (Mr) ~ 0.189 emu/g. The loss of magnetism at higher Sn- ZnO nanopowder was assigned to the suppression of ferromagnetism through paramagnetic interactions. The experimental results showed that 4% Sn- ZnO became ferromagnetic, its lattice shrink and size decreased, which is important for excellent magnetic properties and electrical conductivity. These types of materials have a large number of applications in high-frequency devices, ultrahigh dielectric material gas sensors, spintronics, and optoelectronics.

In this paper, a hydrothermal synthesis method synthesized a foamed nickel (NF)-supported Ag-doped Ag2S@MoS2 hydrogen evolution catalyst. Silver doping can improve the conductivity of MoS2, thereby improving the hydrogen evolution activity of MoS2. Compared with a single MoS2, the Ag2S@MoS2 electrode has a larger specific surface area and has many highly catalytic S edges. In 1 M KOH, the overpotential of Ag2S@Ag0.33MoS2/NF electrode at 10 mA cm−2 is approximately 188 mV. Comparing with the overpotential of NF (391 mV) and MoS2/NF (290 mV), it is much lower. Further changing the amount of silver added, the overpotential of Ag2S@Ag0.5MoS 2/NF is further reduced to 165 mV at a current density of 10 mA cm−2. When the voltage is 0.35 V, the current densities of Ag2S@Ag0.33MoS2/NF (42.45 mA cm−2) and Ag2S@Ag0.5MoS2/NF (55.5 mA cm−2) are higher than those of NF (4.91 mA cm−2) and MoS2/NF (20.51 mA cm−2).

This paper presents an investigation of ultrathin Cu (In1−xGax) Se2 solar cell which was calibrated from the fabricated cell using Silvaco-TCAD tools. Carrier transport mechanism and conduction band alignment at the CdS/CIGS interface shows a large influence on PV parameters. The influence of the absorber trap density on the electrical characteristics of the single junction cell was investigated under AM 1.5G one-sun (100 mW/cm2) illumination. Further simulations quantify significant improvements in cell efficiency while using a thin Al2O3 material as a rear passivation layer. In addition, the impact of the backside pitch size, opening width, absorber layer doping, and thickness on cell performance is investigated to enhance the cell efficiency. To evaluate our work, the electrical characteristics of the optimized cell were compared to the fabricated cells.

Mn8Ga5 alloy has certain significance in the study of materials for magnetic refrigeration applications due to its low coercivity. In this paper, the structure, magnetic properties and magnetocaloric effects (MCE) of Mn8−xCrxGa5 (x = 1.3, 1.7) polycrystalline alloys were first studied by using X-ray diffraction (XRD) technique, scanning electron microscope (SEM), energy-dispersion (EDS) analysis and magnetization measurement. The two samples crystallized in a cubic (Zn8Cu5)-type structure with space group of I-43 m (No. 217). The lattice constants and crystallite sizes of Mn8−xCrxGa5 increase with the increase of Cr concentration. As the Cr content increases, the Curie temperature (Tc) of Mn8−xCrxGa5 (x = 1.3, 1.7) is increased from 145 to 187 K. The saturation magnetic moments of Mn8−xCrxGa5 are 33.8 (x = 1.3) and 36.6 (x = 1.7) emu/g under the magnetic field of 16 kOe at 80 K, respectively. A second-order magnetic phase transition occurred in Mn8−xCrxGa5 alloy samples. The maximum magnetic entropy changes (|∆SM|) of Mn8−xCrxGa5 are 0.9 (x = 1.3) and 0.8 J·kg−1·K−1 (x = 1.7), and the relative cooling power (RCP) values are 25 (x = 1.3) and 17 J/kg (x = 1.7) under 15 kOe magnetic field.

In this paper, Ho3+/Yb3+ co-doped Sodium Gadolinium Fluoride (NaGdF4) phosphors were synthesized by a facile and efficient hydrothermal method. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy spectrum (EDS), and photoluminescence (PL). The results of XRD and SEM indicated that the prepared NaGdF4 samples have the hexagonal structure and good orientation in the case of changing the concentration of Yb3+. The results of pump power dependence of up-conversion intensity indicated that the energy transfer mechanism from Yb3+ to Ho3+ is a two-photon process. The energy transfer between Ho3+ and Yb3+ under 448 nm excitation was determined by PL spectra and fluorescence lifetimes. All the results proved that the doping of Yb3+ ions can effectively improve the up-conversion luminescence of NaGdF4 phosphors and achieve quantum cutting efficiency of up to 179.8%. Overall, NaGdF4:Ho3+/Yb3+ have potential application in the field of optoelectronic materials.

Perovskite solar cells are efficient units in systems with modern renewable energy sources. Increasing the efficiency of solar cells is important in photovoltaic (PV) systems. In this paper, the effect of Zn–Cu–In–Se quantum dots on the performance of thin-film perovskite solar cells is analyzed. The effect of the specification of the perovskite layer, electrical connections and quantum dots has been discussed using modeling of solar cell open-circuit voltage, short-circuit current, spectral response, efficiency, and fill factor. Based on the simulation results, without using Zn–Cu–In–Se quantum dots, the optimal performance occurs in high and low electrode work function as 3.5 eV and 5.93 eV achieving 21.53% energy conversion efficiency. In the proposed perovskite solar cell including Zn–Cu–In–Se quantum dots, 33.56% efficiency can be obtained in the same conditions. More intensity of the electric field inside the perovskite layer and the quantum dots causes to increase the energy conversion efficiency compared to the case without quantum dots. The achievable power in case of Zn–Cu–In–Se quantum dots is 0.275 mW/cm2, which is 35% more than the case without these quantum dots in the solar cell. As shown in simulation results section, many improvements can be achieved via using Zn–Cu–In–Se quantum dots in the perovskite solar cell.

The proposed research work manifests the comparison of nanosized ‘as prepared’ Ni0.5Co0.5Fe2O4 ferrite with their ‘sintered’ counterpart concerning their effect on the structural and magnetic properties. This paper conceptualizes the successful synthesis of Ni0.5Co0.5Fe2O4 ferrite nanoparticles by combustion route and their structural characterization viz. powder X-ray diffraction (XRD), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) studies. The morphological studies like scanning electron microscopy (SEM) and high-resolution-transmission electron microscopy (HR-TEM) proclaimed the cuboidal nature of the particles. The alternating current (AC) susceptibility measurements determined the Curie temperature (Tc), which decreased in the ‘sintered’ ferrite. The vibrating sample magnetometry (VSM) measurements showed an increase in the saturation magnetization and a substantial decrease in coercivity at 300 K and 60 K from nano to bulk ferrite. The temperature-dependent zero-field cooled-field cooled (ZFC-FC) magnetization curves revealed information about the blocking temperature of the ‘as prepared’ and ‘sintered’ ferrites.

In this paper, Au plasmons and their synergistic effects with ZnO nanorods (ZNs) have been investigated for photoelectrochemical (PEC) water splitting application. Au plasmons and ZNs are deposited electrochemically. Au modified nanostructures have absorption in the visible region as plasmons enhance charge transfer and inhibit charge recombination. ZNs modified with Au (deposition duration ∼ 60 s) has a photo-current density of ∼ 660 µA cm-2, at a bias of 1.0V/SCE. X-ray diffraction and scanning electron microscopy were used to study the structure and surface morphology of fabricated photoanodes. UV-Visible absorption and Photoluminescence spectroscopy were used for optical characterization. We have recorded current-voltage measurements and photo-conversion efficiency measurements to substantiate our observations of the synthesized photoanodes for prospective application in PEC splitting of water. We have also carried out Mott-Schottky, and electrochemical impedance spectroscopy analysis. The analysis reveals that Au modified ZNs based photoanodes are a better proposition than their bare counterparts for PEC water splitting application.

In this work, ferroferric oxide (Fe3O4) microspheres with a diameter of ~ 150 nm were in situ grown on the surface of graphene oxide (GO) to obtain GO@Fe3O4 hybrids. Then, novel PMIA/CF/GO@Fe3O4 electromagnetic shielding composites have been developed with a simple and efficient paper-making method using poly(m-phenylene isophthalamide) (PMIA) fibers as matrix and carbon fiber (CF) and GO@Fe3O4 as fillers. Due to the introduction of GO@Fe3O4 and a large number of voids into the materials, the obtained PMIA/CF/GO@Fe3O4 composites exhibit good magnetic sensitivity and low density. Besides, the obtained PMIA/CF/GO@Fe3O4 composites with 10 wt% GO@Fe3O4 loading shows outstanding EMI-shielding effectiveness (EMI SE) of 42.55–46.98 dB at 8–12 GHz, and as the content of GO@Fe3O4 increases to 30 wt%, the EMI SE increases to 55.22 to 60.23 dB. The EMI SE of the PMIA/CF/GO@Fe3O4 composites is far more than the target value (20 dB) required by practical application. Thus, it provides a path to obtain a new class of high-performance and lightweight PMIA-based composites for enhanced shielding of electromagnetic pollution.

Herein a double shells structure was proposed to overcome the drawbacks such as poor heat resistance, incomplete insulation and high core loss coating of iron-based soft magnetic composites (SMCs) with single shell structure. The surface of the iron powder was coated with a double shells structure composed of an inner phosphate coating and an outer SiO2 coating through phosphating and hydrolysis successively. Subsequently, the effects of different SiO2 addition amount on the microstructure of iron powder and magnetic properties of SMCs were studied. The introduction of SiO2 in the double shells structure inhibited the decomposition and failure of phosphating layer after being annealed at a high temperature. The iron powder coated with the phosphate-SiO2 insulating layer was still effective after annealing in a N2 atmosphere at 570 °C, achieving the purpose of eliminating residual stress and improving magnetic properties. The optimal process parameters were set at 0.2 wt% phosphoric acid and 0.5 wt% tetraethyl orthosilicate to fabricate the phosphate-SiO2 double shells. The iron-based SMCs presented excellent magnetic properties with Bs of 1.29 T and Ps of 169.2 W/kg (measured at 1 T and 1 kHz). In addition, the core loss of SMCs introduced with SiO2 is 83% lower than that of SMCs produced by the phosphating process. This paper provides a feasible method for improving the magnetic properties of SMCs.

The coupling effect and synergistic effect between the two metal elements of the bimetallic oxide make it has unique electrical characteristics and gas-sensitive properties, but it has the limitation of low conductivity. In this paper, the bimetallic oxide Zn2SnO4 was decorated with reduced graphene oxide (rGO) to increase its electrical conductivity and promote charge transfer during gas adsorption, which enhances the response and shortens the response time of the bimetallic oxide gas sensor. The high-performance ammonia sensor based on Zn2SnO4/rGO nanocomposite material was prepared by environmentally friendly hydrothermal method and spin coating technology. The structure and properties of composite materials were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The ammonia sensing performance of Zn2SnO4/rGO nanocomposite sensor was tested at room temperature, including the dynamic response, response/recovery time, selectivity, repeatability, long-term stability. It showed a good sensing response to ammonia (22.94 for 100 ppm), and a fast response/recovery time (20 s/27 s). Finally, the response mechanism of Zn2SnO4/rGO nanocomposite sensor is explained. The enhanced ammonia sensing properties of Zn2SnO4/rGO nanocomposite sensor were ascribed to the synergistic effect and p–n heterojunction between Zn2SnO4 and rGO.

In the present paper, we have performed the Fourier transform infrared (FTIR) and thermoluminescence (TL) characterizations of gamma-irradiated (dose 0.5–50 kGy) colorless natural quartz of Indian origin. Investigations of structural changes in irradiated quartz crystal in terms of crystallinity index have been carried out based on assignment of infrared bands of SiO4 tetrahedron in the fingerprint mid-infrared region. Colorless quartz containing aluminum as impurity modifies its color to dark smoky after exposure to ionizing radiations. The TL glow curves analysis shows that there are four trapping sites corresponding to four TL peaks at 169, 212, 279 and 370 °C. Chen’s peak shape method and initial rise method have been used to determine the kinetic parameters (order of kinetics, activation energy and frequency factor). The role of [AlSiO4/h+]0 (substitutional center formed on replacement of Si4+ with Al3+ and charge compensated by a hole) centers in color development and as luminescence centers is discussed by making a correlation between FTIR and TL studies.

Phase change memory (PCM) is regarded as a promising candidate for next-generation data storage devices. However, the contradiction between crystallization speed and amorphous thermal stability is still a great challenge. In this paper, we demonstrate PCM based on Ru-doped Sb2Te (RST) alloy, showing 112 °C 10-year data retention, 229 °C crystallization temperature, 6 ns Set speed, and 85% reduced power consumption compared to Sb2Te(ST)-based device. The good performance attributes to the grain refinement of the crystalline films with inclusion of Ru, making it a promising material for high-speed and good thermal stability phase change memory applications.

[EN] The Fluorescence sensing technique for trace detection of High Energy Materials (HEMs) has gained more attention in recent times. In the present paper, the interaction between the fluorophore and HEMs is studied using spectroscopic and electrochemical techniques. The fluorophore polyaniline (PANI) was functionalised by doping it with benzenesulfonic acid (BSA) to increase the processability, and mobility of ¿-electrons along with decreased ¿-stacking. It is observed that upon doping the solubility of BSA-PANI is increased, facilitating a higher quenching by commercial explosives, i.e., RDX, CL-20, CL-20:RDX cocrystal. The interaction studies undertaken though fluorescence quenching, FTIR and Resonance Raman studies shows that the benzenoid unit, polaron and bipolaron nitrogen in BSA-PANI interact with nitro groups of HEMs and form a charge-transfer complex between HEMs and BSA-PANI undergoing predominantly a PET mechanism. LOD value is found to be least for Cocrystal (1.876¿×¿10¿5 M) when compared to other HEMs 3.191¿×¿10¿5 M (CL-20), 5.904¿×¿10¿5 M (RDX), 3.734¿×¿10¿5 M (PETN) indicating that cocrystal can be detected in trace level. The collaborative study between cyclic voltammetry and the observed results of fluorescence quenching, revealed that the emeraldine salt form of (BSA-PANI) is sensitive to HEMs., The authors acknowledge and thank Prof. G. U. Kulkarni, the former Director of Centre for Nano and Soft Matter (CeNS) for providing the facility to work in the centre. The authors, S A Ture and V B Patil, expresses their thanks to M/s Premier Explosive Limited for their Financial support (H/A: 4254), the corresponding author expresses his thanks to UGC, New Delhi for the BSR faculty fellowship [F.4-5(11)/2019(BSR)]. We also thank the Spanish Government [RTI2018-100910-B-C41 (MCUI/AEI/FEDER, UE)] and Generalitat Valenciana (PROMETEO2018/024) for their support.

In this paper, a plasmonic sensor consists of a bimetallic layer of Ag and Au, a nano-thin layer of two-dimensional material MXene and a thin layer of Magnesium oxide (MgO) is proposed to operate in a visible region. Using Kretschmann configuration-based structure and transfer matrix method, the change in the refractive index of liquid Biosample have been observed at a fixed incident wavelength. Using the distinctive properties of Ti3C2Tx MXene and MgO, we have investigated the performance of Surface Plasmon Resonance (SPR) biosensor. Significant performance parameters such as Sensitivity, Figure of Merit (FoM) and Detection Accuracy (DA) calculated for different cases to prove the capability of proposed sensing structure. We also compared the sensitivity and sharpness of SPR curve obtained when using conventional adhesion layers such as titanium (Ti), chromium (Cr), and tantalum (Ta). A detailed investigation is carried out to observe the role of polymer as an adhesion layer and its thickness impact on FoM and resonance angle sharpness. The concept of Long range SPR (LR-SPR) and Short range SPR (SR-SPR) are also discussed.