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This prospective and performance summary provides a view on the state of the art of emerging non-volatile memory (eNVM) in the semiconductor industry. The overarching aim is to inform academic researchers of the status of these technologies in industry, so as to help direct the right academic research questions for future materials and device development. eNVM already have a strong foothold in the semiconductor industry with the main target of replacing embedded flash memory, and soon possibly DRAM and SRAM, i.e. replacing conventional memory. Magnetic and resistive memory are the current frontrunners among eNVM for embedded flash replacement and they are very advanced in this, which poses high demands on future academic research for eNVM for this purpose. Phase-change and ferroelectric memory are less available as commercially available products. The use of eNVM for new forms of artificial intelligence hardware is a much more open field for future academic research. [ABSTRACT FROM AUTHOR]

Phosphaphenalenes, extended π conjugates with the incorporation of phosphorus, are attractive avenues towards molecular materials for the applications in organic electronics, but their electron accepting ability have not been investigated. Herein we present systematic studies on the reductive behavior of a representative phosphaphenalene and its oxide by chemical and electrochemical methods. The chemical reduction of the phosphaphenalene by alkali metals reveals the facile P−C bond cleavage to form phosphaphenalenide anion, which functions as a transfer block for structure modification on the phosphorus atom. In contrast, the pentavalent P‐oxide reacts with one or two equivalents of elemental sodium to form stable radical anion and dianion salts, respectively. [ABSTRACT FROM AUTHOR]

Flexible strain sensors are being increasingly applied as wearable electronic materials owing to their functional characteristics (e.g., light weight, stretchability, wearability), which highlight their enormous potential in health monitoring and medical care. However, challenges related to signal distortion and corrosion risks arise when they are used under extreme or harsh conditions. Superhydrophobic flexible strain sensors combine the water‐repellent, anticorrosion, and anti‐fouling features of the superhydrophobic coating with the high ductility and high sensitivity of the flexible strain sensor, thereby broadening the application scope of strain sensors, especially for underwater wearable sensing. However, the underwater sensing applications of superhydrophobic flexible strain sensors have not yet been thoroughly summarized. This review presents the key performance parameters and design strategies of superhydrophobic flexible strain sensors, with an emphasis on the diverse applications for underwater sensing. [ABSTRACT FROM AUTHOR]

Here, we study the impact of a polyvinylpyrrolidone (PVP) additive on cesium-based lead halide perovskites. We demonstrate the control of phase, morphology, film stress, and ion concentration under accelerated aging with the use of PVP in CsPbI3. The addition of PVP in all-inorganic metal halide perovskites (MHP) further induces a residual compressive film stress, a factor that is correlated with improved film stability. The removal of PVP increased the stress based on a contraction in the film. Under thermal cycling, thermal aging, and light-induced aging, all-inorganic MHP films experienced negligible bandgap change and comparable ion behavior with and without PVP removal. [ABSTRACT FROM AUTHOR]

Hybrid perovskites have attracted great interest in solar energy conversion and optoelectronic applications. The interconnected ionic and electronic effects complicate assessing the underlying electrical processes while contributing greatly to the efficiency and stability of devices. Fortunately, these coupled processes manifest on distinct timescales that enable frequency-specific electrochemical analysis. However, hybrid perovskites dissolve in most of the common aqueous and organic solvents utilized for electrochemistry. Here, we utilize a hydrofluoroether (HFE) solvent toolkit to perform nondestructive electrochemical impedance spectroscopy of methylammonium lead iodide (MAPbI3) perovskite thin films. This enables the extraction of dielectric constants and double-layer formation in these perovskite films. [ABSTRACT FROM AUTHOR]

We present one-pot colloidal synthesis of copper indium telluride (CITe) from respective metal salts with sodium tellurite in 1-octadecene with variation in surfactant and the reaction temperature between 200 and 300 °C. Oleic acid and/or oleyl amine are employed to initially, generate tellurides of individual element at intermediate stage. The tuning of reaction parameter including temperature variations play important role for the formation of phase-pure CuInTe2 nanocrystals with a band-gap of about 1.15 eV. The phase-purity was confirmed by XRD. EMI Shielding efficiency of CITe/PVA film can be enhanced to the tune of −8.84 dB by use of silver nano-particles. The composite can be suitable for X-band applications.

This work examined the development of the transient current of a ferroelectric thin film such as (Hf,Zr)O2, Pb(Zr,Ti)O3, and (Al,Sc)N to clarify the origin of the decrease in transient current during switching. Toward this end, the measured transient switching current of the ferroelectric capacitor was simulated while considering the coercive voltage distribution across the capacitor area. Furthermore, to understand how the non-ferroelectric interfacial layer behaved, the Al2O3 capacitor was serially connected to the ferroelectric capacitors. The coercive voltage distribution of the ferroelectric layer determined the slope of the current plateau, and the non-ferroelectric layer behaved like resistance during switching. [ABSTRACT FROM AUTHOR]

The ceramic composite electronic material of (Sn0.8Ti0.2)O2 has been synthesized through a cost-effective solid-state ceramic approach. The crystallographic tetragonal structure from the XRD spectrum, hydrophilic porous structure from SEM micrograph, dielectric, conductivity, and electrical modulus in addition to impedance spectroscopy over an extensive range of temperature and frequency have been elucidated. Hydrophilicity, superior dielectric response with significantly low dielectric loss, and enhanced capacitive behaviour draw the major attraction of this ceramic-based material system. The temperature-dependent conductivity spectrum evinces Arrhenius's behaviour. The grain and grain boundary effects in the synthesized sample has been displayed through the Nyquist spectrum. The non-Debye type of relaxation mechanism has been established through an electric modulus study. The extensive study sketched out this composite as a potential capacitive electronic component for humidity sensor device applications. The investigated electrical parameters associated with the ceramic composite may enlighten the development of functional electronic devices. [ABSTRACT FROM AUTHOR]

To enhance the excellent light management capability, the GaN nanowire array (NWA) resonator is designed. When the diameter D = 120 nm, the height H = 750 nm, and the period P = 240 nm, the maximum resonance-enhanced optical absorption can be obtained at a resonance wavelength of 341 nm, the value is about 98%. The carrier concentration is mainly concentrated inside the nanowire, and the light reflection at the resonance wavelength is reduced to about 3%. These factors comprehensively enhance the quantum efficiency (QE). The QE of the GaN NWA cathode is 2.7 times as long as that of the GaN planar cathode. [ABSTRACT FROM AUTHOR]

The low responsivity of conventional Silicon photodiodes in ultraviolet and near-infrared regimes restricts their utility as broadband photodetectors (BBPDs). Despite ongoing investigations into various p-n heterostructures for Silicon-based BBPDs, challenges such as high dark current (I _dark ), low collection efficiency, low detectivity, and compatibility issues with large-scale Silicon-based devices persist. In this context, we have fabricated relatively unexplored n-Er _2 O _3 /p-Si heterojunction-based BBPDs. Polycrystalline Er _2 O _3 thin films (∼110 nm) were deposited on p-Si 〈100〉 substrates by radio frequency magnetron sputtering. Although this process induces a microstrain of approximately 0.022 and a dislocation density of about 0.00303/nm ^2 , the presence of optically active defects is minimal, indicated by a low Urbach energy (∼0.35 eV). X-ray photoelectron spectroscopy (XPS) analysis confirms staggered band alignment at the heterointerface, facilitating efficient charge carrier separation and transport. Consequently, the In/p-Si/n-Er _2 O _3 /In device demonstrated significant BBPD properties– low I _dark ∼0.15 μ A (at +5 V), photo-to-dark current ratio (PDCR) ∼6.5 (at +5 V, 700 nm) with a maximum photoresponsivity ∼22.3 A W ^−1 , and impressive detectivity (∼10 ^13 Jones) even in UV-C region where traditional silicon-based photodetectors respond feebly. The device also demonstrates transient photo-response across an ultrawide spectrum (254 nm–1200 nm) with a fast rise time/fall time ∼79 ms/∼86 ms (at −5 V for 600 nm illumination). This work establishes a straightforward and reliable method for proper material engineering, surface texturing, staggered heterojunction formation, and high-performance BBPD fabrication with prominent broad-spectrum responsivity, sizeable detectivity, and fast response. The integration of these BBPDs with Silicon opens possibilities for their use in electronic devices containing optical switches for communications and broadband image sensors, enhancing their utility in various applications.

Devices containing transition metal dichalcogenides are being investigated for next generation electronics. Understanding material properties under typical use conditions is important for the longevity and effectiveness of these devices. In this study, CVD-grown MoS2 crystals with pre-existing defects from the growth process were subjected to DC-voltages of 10 V, 20 V, and 40 V for up to 96 h. The presence of pre-existing defects was found to lead to more extensive material damage that scales with voltage and time. SEM, AFM, Raman and photoluminescence imaging indicated regions of increased defect concentration post-electrical stress. [ABSTRACT FROM AUTHOR]

We investigated the field emission of graphdiyne-C60 nanocomposite by using first principle calculation. The results show that graphdiyne obtains good electrical performances such as high level of emission currents. The construction with C60 cluster and graphdiyne can take full advantages of the curvature effect and the tip effect of C60 cluster which induces local charge improvement. It shows that the C60 cluster can strengthen the field emission of graphdiyne-C60 nanocomposite. It implies that the graphdiyne-C60 nanofabrication could have a potential application for field emission electron sources in the future. A novel graphdiyne-C60 nanocomposite is proposed for field emission electron sources. We investigated field emission mechanism of graphdiyne-C60 nanocomposite. We detected that graphdiyne has a high level of emission currents with a low external electric field. We detect the curvature effect and the tip effect of C60 cluster that induce local charge enhancement. It implies the graphdiyne-C60 nanofabrication maybe a candidate of field emission electron sources. [ABSTRACT FROM AUTHOR]

Samarium substituted BiFeO 3 –PbTiO 3 ceramic compound of (Pb 0.6 Sm 0.2 Bi 0.2)(Fe 0.4 Ti 0.6)O 3 has been fabricated by mixed oxide solid state reaction method. The crystallographic structure from XRD study, distribution of grains from SEM micrograph, dielectric behavior, conductivity spectrum, impedance along with electric modulus spectroscopy have been illustrated. The experimental results corroborate the impact of samarium substitution in BiFeO 3 –PbTiO 3 entailing reduced grain size, higher dielectric response with reasonably dielectric loss and enrichment in capacitive behavior with negative temperature coefficient of resistance. The temperature dependent conductivity spectra exhibit Arrhenius behavior, whereas the frequency dependent conductivity spectra follow the Jonscher universal power law. The basic correlated barrier hopping (CBH) model governs the charge transport mechanism in the fabricated compound. The exploration reveals the enriched dielectric and electrical behavior that endorse the samarium substituted material as a potential ceramic entity for designing electronic devices such as capacitors and ferroelectric accessories. [ABSTRACT FROM AUTHOR]

To determine the arc-erosion behavior at different electrical contact modes for titanium diboride-nickel co-reinforced (Ag-TiB2-Ni) and nickel-enhanced (Ag-Ni) silver-based electrical contact materials, Ag-4 wt.%TiB2-4 wt.%Ni and Ag-8 wt.%Ni contact materials were fabricated by metal metallurgy and spark plasma sintering. The arc-erosion tests were respectively performed at make-only, make-break (M-B), and break-only modes. The eroded morphology, arc duration/energy, mass change, material transfer, welding, and arc waveforms at different modes were comparatively investigated for the Ag-TiB2-Ni and Ag-Ni contact materials. The results show that the Ag-4TiB2-4Ni contact material presents a discrete distribution of arc duration/energy, low arc stability, and seriously damaged surface, while a concentrated distribution of arc duration/energy, high arc stability, and concentrated crater/protrusion morphology appear for the Ag-8 wt.%Ni contact material. Additionally, the Ag-4TiB2-4Ni contact material shows material transfer from anode to cathode, but the transfer occurs in the reverse direction for the Ag-8Ni contact material. Moreover, at the make-only mode, it presents a higher make-arc-duration than that at the M-B mode, whereas the lower break-arc-duration appears at the break-only mode rather than at the M-B mode for the Ag-8Ni contact material. For the Ag-4TiB2-4Ni contact material, however, the make-arc resistance shows a slower degradation rate at the make-only mode than that at the M-B mode, but at both break-only and M-B modes it has a similar deterioration speed in the break-arc resistance. The difference in arc parameter and material transfer is derived from the various material properties which effectively influence the formation of a molten bridge and metal evaporation. [ABSTRACT FROM AUTHOR]

A new nanocomposite of graphene oxide (GO) functionalized with polyaniline (PANI) doped with silver was synthesized. The monomer was oxidized on the surface of the graphene oxide afterward was treated with the silver nitrate solution. The composite polyaniline@graphene oxide/Ag (PANI@GO/Ag) was subjected to the characterization with various spectrophotometric instrumental methods such as, SEM-EDX, TGA, FTIR, UV–vis etc. The four probe electrical conductivity of the PANI@GO/Ag was determined that showed its semiconductor nature. Cyclic and isothermal conductivity study of the composite was shown excellent results in the perspective of strong material. The property of the composite was cashed for the designing of ion sensitive membrane electrode for Cd2+ heavy metal from the waste water. Different physical parameters of ion-sensitive membrane electrode such as, Nernstian slope (26.20 mV/decade conc change); working pH range (2–6); response time (15 s) was determined. The analytical utility of this composite ion sensitive membrane as an indicator electrode in different titrations for municipal wastewater.

We present calculations of performance characteristics of Indium Gallium Nitride-Silicon Heterojunction Schottky barrier solar cells. The effect of growth axis and spontaneous and piezoelectric effects in the Indium Gallium Nitride are taken into account. We consider both wurtzite Indium Gallium Nitride layers on 111 silicon and cubic indium gallium nitride layers on 100 silicon. The short-circuit current as a function of depletion-layer thickness is studied along with the effect of Indium Gallium Nitride composition on the dark current. We consider the effect of composition grading on solar cell characteristics. Greater than 20% power conversion efficiency is achievable with a simple quasi-unipolar design. [ABSTRACT FROM AUTHOR]

Nonlinear optical crystalline material is the fascinating tool for the optoelectronic devices and for phase-matched equipments, frequency matching circuits and etc. Present study portrays the synthesize and utility of macro and nano scaled crystals of 2-[4-(trifluoromethyl) phenyl]-1H-benzimidazole (TFMPHB) by slow evaporation solution growth method and by milling conversion. As-prepared crystals were studied by XRD, CHNSO analysis, dielectric and tribology-mechanical, NLO, and photoconductivity. The orthorhombic phase structure with the average crystalline size of 21 nm was observed. The elemental composition of crystals was analyzed for the presence of elements. Tribological studies of macro and nano TFMPHB crystals were favorable for mechanical applications. Further, the high dielectric constant (363 K) at low frequency was suitable for microelectronic devices; NLO is analyzed with phase matching effect over particle size, and photoconductivity study also reported for the entitled crystalline specimen. The structural parameters by AFM and SEM, absorbance nature by UV spectra, and modeling data by computational methods are also reported. [ABSTRACT FROM AUTHOR]

3D-printed polymer structures were successfully metalized by a supercritical carbon dioxide (scCO2)-assisted electroless plating process. ScCO2 was used as the solvent in the catalyzation step, and the source of the catalyst was palladium bis-hexafluoroacetylacetonate. Ni–P coatings were deposited on surfaces of the catalyzed polymer structure with a commercially available solution. Electrical resistance of the Ni–P metallized polymer structure was measured, and the adhesion of the Ni–P coating on the polymer structure was evaluated by a tape adhesion test. The electrical resistance was 0.03 Ω and maintained at a low level of 0.04 Ω after the tape adhesion test. [ABSTRACT FROM AUTHOR]

Ternary NiCo2O4 has paying more attention as a class of potential electrochemical energy storage materials. In the present endeavor, we report spinel NiCo2O4 nanoplates, which were prepared by cetyl trimethyl ammonium bromide (CTAB)-assisted hydrothermal technique followed by proper calcination process. The structural and morphological features were characterized by x-ray diffraction, Fourier transform infrared spectra, scanning electron microscope and high-resolution transmission electron microscopic analyses. The supercapacitive properties of the materials were evaluated using cyclic voltammetric, electrochemical impedance spectroscopy and galvanostatic charge/discharge analysis in 1 M NaOH electrolyte. The freshly prepared NiCo2O4 materials offer the specific capacitance of 329 mA h g−1 at a current density of 1 A g−1, and it provides superior long-term cyclic stability, which retained 97% of initial capacitance after 2000 continuous CV cycles at a high scan rate of 100 mV s−1. These outcomes demonstrate thus prepared spinel NiCo2O4 as a significant electrode material for supercapacitor application. [ABSTRACT FROM AUTHOR]

Exploring as well as examining novel functional double perovskite material represents an important aspect in the field of electronic devices. In this present study the electronic material Bi2MnNiO6 has been framed through high temperature solid state ceramic processing method. Its electronic structure, morphological and electrical characteristics has been evaluated. Its structure is found to be monoclinic through XRD analysis. The uniform and compact grain distribution has been observed form the micrographs. The impedance analysis of the ceramic suggests negative temperature coefficient of resistance behaviour. The important electrical properties associated with this compound may be essential in the development of next generation electronic devices. [ABSTRACT FROM AUTHOR]

A multiple cation containing sample as [(Pb0.8Dy0.1Bi0.1)(Fe0.2Ti0.8)O3] is fabricated by adopting the solid-state reaction process. The crystallographic structure, crystallite size, morphology, dielectric behavior, conductivity, polarization, impedance as well as electric modulus spectroscopy are experimentally observed for this fabricated composition. The crystal structure of the specimen is observed to be tetragonal from X-ray diffraction. The micrograph shows the presence of polycrystalline microstructure with uniform distributed grains. The impedance spectroscopy analysis as a function of temperature (100–450 °C) and frequency (1–1000 kHz) helps to signify the resistive and capacitive behavior of the compound. The nature of the prepared specimen and conduction mechanism is illustrated through AC conductivity study. The modulus analysis elucidates the existence of non-Debye dielectric relaxation nature in the synthesized compound. The compound possesses appreciable value of loss tangent and remnant polarization, i.e., 0.02 and 0.014 µC/cm2, with high value of dielectric constant at room temperature. The dysprosium doping entails stability with interesting electrical and dielectric properties. The preliminary capacitive characteristic has been elucidated, thus making it a stronger contender for functional device applications. [ABSTRACT FROM AUTHOR]

Zinc sulfide (ZnS) and n-type zinc oxide (ZnO) nanostructures have been synthesized and deposited on p-type porous silicone to investigate their photovoltaic properties. The morphology of the synthesized structures has been investigated via scanning electron microscopy and it has been determined that the structures are in the nanoscale. Energy dispersive spectroscopy has been used to investigate the composition of the synthesized structures, and it has been determined that they have defects. The absorption measurements have been performed by ultraviolet–visible spectrophotometry. Based on these absorption measurements, the band gaps of the nanostructures have been calculated as 3.11 eV for spherical ZnO, 3.12 eV for flowers ZnO and 3.64 eV for ZnS. The nanostructures were deposited to obtain thin films in different thicknesses by using a spin-coating method on porous p-type silicone substrates, and then the photovoltaic and electrical properties were investigated. According to the obtained experimental results, it has been determined that the photovoltaic properties of the sample depend on the film thickness. Consequently, ZnS and n-type ZnO nanostructures have been synthesized by a sol–gel method and it has been found that they have photovoltaic properties. [ABSTRACT FROM AUTHOR]

In this report, Ba1Bi1Cu1Fe1Ni1Ti3O12 (BBCFNTO termed further) ceramics were synthesized using a conventional ceramic processing route. The formation of multiple phases has been confirmed from by the XRD pattern at room temperature. The surface micrograph indicates the uniform distribution of grains with distinct grain boundary. The co-relation between the impedance and dielectric parameters was realized by using a phase sensitive meter over a good temperature and frequency range. The temperature- and frequency-dependent dielectric properties are linked to the conduction mechanism. The dielectric constant (K) and loss (tanδ) are increased sharply at high-temperature region, which is expected to be the onset of dipolar relaxation phenomena. The contribution of grain boundary (GBs) and grain (Gs) effects can be identified using the complex impedance spectroscopy. This synthesized material is investigated to model multifunctional devices. [ABSTRACT FROM AUTHOR]

In this report, Ba1Bi1Cu1Fe1Ni1Ti3O12 (BBCFNTO termed further) ceramics were synthesized using a conventional ceramic processing route. The formation of multiple phases has been confirmed from by the XRD pattern at room temperature. The surface micrograph indicates the uniform distribution of grains with distinct grain boundary. The co-relation between the impedance and dielectric parameters was realized by using a phase sensitive meter over a good temperature and frequency range. The temperature- and frequency-dependent dielectric properties are linked to the conduction mechanism. The dielectric constant (K) and loss (tanδ) are increased sharply at high-temperature region, which is expected to be the onset of dipolar relaxation phenomena. The contribution of grain boundary (GBs) and grain (Gs) effects can be identified using the complex impedance spectroscopy. This synthesized material is investigated to model multifunctional devices. [ABSTRACT FROM AUTHOR]

The polycrystalline 0.7Bi(Fe 0.98 Ga 0.02)O 3 -0.30BaTiO 3 (BFG-BTO) ceramic was processed by high temperature reaction route. The room temperature X-ray spectra suggest a tetragonal symmetry. The structural refinement was also carried out. The high densification of sample formation is depicted from a scanning of the natural surface of the sample. The electrical properties were measured using a complex impedance method over a wide range of frequencies and temperatures. The overlapping large-polaron tunnelling model type of conduction mechanism is obtained from the frequency dependent ac conductivity plots. The relaxation mechanism is studied with the help of various spectroscopic tools (modulus and dielectric). The Nyquist plot indicates the non-Debye characteristics and the combined contribution of both grain and grain boundary towards the resistive property of the sample. Image 1062858 • The BFG-BTO is synthesized by cheap cost ceramic processing. • Dielectric properties with respect to temperature is investigated. • The complex impedance plots shows grain and grain boundary effects in the BFG-BTO. • A well defined relaxation mechanism was identified by modulus analysis. [ABSTRACT FROM AUTHOR]

Write Once Read Many (WORM) Memory, as one of the most important nonvolatile memory type, has widespread used in a variety of permanent storage applications in the Big Data age. As an excellent material, CsPbBr 3 quantum dots have widely used in a lot of photoelectric devices, but CsPbBr 3 quantum dots based memory device remain to be studied. In this work a WORM memory device based on CsPbBr 3 quantum dots is demonstrated. The CsPbBr 3 QDs based WORM shows great reproducibility, good data retention ability, irreversible electrical transition from the high resistance state (HRS) or OFF state to the low resistance state (LRS) or ON state and the resistance ratio (ON/OFF) can reach almost 104. Additionally, the device exhibits high performances under low power consumption — low reading voltage (−0.5 V) and writing voltage (−1.1V). To study the CsPbBr 3 QDs based WORM provides an opportunity to develop the next generation high-performance and stable WORM devices. • We present a sandwiched WORM based on CsPbBr 3 AIPQDs by solution processed method. • Our CsPbBr 3 AIPQDs based WORM shows great reproducibility, good data retention ability. • The resistance ratio (ON/OFF) of the WORM device between the OFF and ON state can reach almost 104. • Additionally, the device exhibits high performances under low power consumption — low reading voltage (−0.5V) and operation voltage (−1.1V). [ABSTRACT FROM AUTHOR]

Electronic products enhance our lives and bring change in almost every field including communications, entertainment, and healthcare. However, the fast-growing surplus of electronic waste has become a serious challenge to the environment: the majority of these toxic materials are deposited directly into landfills or incinerated because recycling is difficult and/or expensive. Electronic devices manufactured with biocompatible and biodegradable polymers are in demand because they are environmentally safe, of low cost, of potentially large volume, and are disposable. In addition, biocompatible and biodegradable electronics may enable the use of electronic devices in implantable biomedical applications. This review is focused on polymer materials, both natural and synthetic, that are utilized in biodegradable and/or biocompatible electronic devices as substrates, dielectrics, conductors, or semiconductors. Specific application examples are highlighted, such as biodegradable electronic devices, implantable medical devices, and edible sensors. [ABSTRACT FROM AUTHOR]

Abstract A series of pyrite thin films were deposited in-situ in a monolayer-by-monolayer fashion using sequential evaporation of iron under high vacuum, followed by sulfidation at a sulfur pressure of 133 Pa, as a function of substrate temperature. The stoichiometry, crystallinity, topographic smoothness, and phase purity of the deposited pyrite thin films improve with increasing substrate temperature up to 420 °C, the highest temperature studied. Characterization of the films deposited at 420 °C using selected-area precession electron diffraction, Raman Spectroscopy, and conventional X-ray diffraction indicated that the pyrite layer is phase pure, with no evidence of a secondary marcasite phase, and grew in columnar grains with a preferential (100) orientation on the (100) silicon substrates. This novel sequential evaporation technique has the potential to make useful low-cost semiconducting pyrite materials for large-area electronic applications. Highlights • A sequential vapor deposition method produced high–quality, pyrite thin films • Films deposited at >400 °C exhibit ideal stoichiometry and ~100% phase purity. • Film grown at 420 °C have columnar grains with pyrite (100)||(100) Si substrate. [ABSTRACT FROM AUTHOR]

Supercapacitors (SCs) have drawn considerable attention as one of the energy storage devices. The key to fabricating flexible supercapacitors lies in the acquirement of flexible electrodes. In this study, the manganese oxide (MnO2) and reduced graphene oxide (RGO) hybrid films (MnO2/RGO) were prepared by a filtration deposition and thermal reduction technique. Electrochemical measurements show that the hybrid films exhibit a specific capacitance of 333.9 F g−1 at 0.5 A g−1, and 87% capacitance after 3000 cycles at 0.5 A g−1. The flexible symmetric SCs was further fabricated with two pieces of MnO2/RGO hybrid films as electrodes. The fabricated flexible and sandwich type symmetrical SCs exhibited a safe working range with a potential window of 0-0.7 V with a maximum energy density of 23.5 Wh kg−1 at 0.5 A g−1 and the maximum power density of 1716.9 W kg−1 at 2.25 A g−1. [ABSTRACT FROM AUTHOR]

Electron transport layers (ETLs) with suitable energy level alignment for facilitating charge carrier transport as well as electron extraction are essential for planar heterojunction perovskite solar cells (PSCs) to achieve high open-circuit voltage (VOC) and short-circuit current. Herein we systematically investigate band offset between ETL and perovskite absorber by tuning F doping level in SnO2 nanocrystal. We demonstrate that gradual substitution of F-into the SnO2 ETL can effectively reduce the band offset and result in a substantial increase in device VOC. Consequently, a power conversion efficiency of 20.2% with VOC of 1.13 V can be achieved under AM 1.5 G illumination for planar heterojunction PSCs using F-doped SnO2 bilayer ETL. Our finding provides a simple pathway to tailor ETL/perovskite band offset to increase built-in electric field of planar heterojunction PSCs for maximizing VOC and charge collection simultaneously. [ABSTRACT FROM AUTHOR]

In this communication we have compared the dielectric behavior of cobalt aluminate mullite (CAM) nanocomposite and cobalt aluminate mullite polymer (CAMP) nanocomposite with different molar concentration of Co +2 ions. The study of dielectric property of the CAM samples as well as that of the CAMP samples at room temperature shows that at all concentrations the dielectric constant is higher than pure mullite and there is a critical concentration of Co +2, where maximum enhancement of dielectric property occurs. This paper demonstrates that the loading of a conductive component into a highly insulating matrix is an effective way to fabricate composites with high permittivity as well as a charge storage material. We have designed a device using CAM as the electrode material and CAMP as the separator to compare it with a commercial Li-polymer ion mobile battery. We observed that the charge storage ability of the composite system is better than the commercial Li-polymer ion mobile battery. Our device persists for more than 24 h while the maximum voltage recorded by the device is 0.885 V, whereas the maximum voltage recorded by the conventional commercial Li-polymer ion mobile battery is 0.566 V. [ABSTRACT FROM AUTHOR]

A new package called 2DRoptimize has been released for performing two-dimensional searches of the equation of state (EOS) for rhombohedral, tetragonal, and hexagonal compounds. The package is compatible and available with the WIEN2k package. The 2DRoptimize package performs a convenient volume and c/a structure optimization. First, the package finds the best value for c/a and the associated energy for each volume. In the second step, it calculates the EoS. The package then finds the equation of the c/a ratio vs. volume to calculate the c/a ratio at the optimized volume. In the last stage, by using the optimized volume and c/a ratio, the 2DRoptimize package calculates a and c lattice constants for tetragonal and hexagonal compounds, as well as the a lattice constant with the α angle for rhombohedral compounds. We tested our new package based on several hexagonal, tetragonal, and rhombohedral structures, and the 2D search results for the EOS showed that this method is more accurate than 1D search. Our results agreed very well with the experimental data and they were better than previous theoretical calculations. [ABSTRACT FROM AUTHOR]

Organic–inorganic halide perovskite solar cells (OIHPSCs) offer a fantastic opportunity to harness solar energy in a low cost and efficient way. This ambition for commercialization has been greatly encouraged by the surge in device performance from 3.8% in 2009 to the state-of-the-art 22.7%. For high device performance, tailoring the interfacial properties is demonstrated essentially important. Being in a molecular scale, the self-assembly monolayers (SAMs) are proved a facile but effective tool for interface modification. And lots of studies have demonstrated that SAMs have a variety of positive effects for perovskite solar cells, including mediating the morphology, improving energy level alignment, passivating trap states, etc. In this mini review, we give an insightful summary on the recent application of SAMs in OIHPSCs, analyze the mechanisms to improve device performance, and provide guidance to SAM-boosted perovskite solar cells for high performance and practical application. Finally, a landscape is depicted for future application of SAMs in perovskite solar cells. [ABSTRACT FROM AUTHOR]