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Large area single and bilayer graphene are grown on Pt/Ti/SiO2 substrates by hot filament chemical vapor deposition (HFCVD) with and without the assistance of Cu foil. The quality and number of graphene layers deposited on the substrate are assessed by Raman Spectroscopy. Atomic Force Microscopy (AFM) is used for assessing the surface topography of the graphene films grown on the Pt/Ti/SiO2 substrates. The microstructure and elemental analyses are performed by Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results show that bilayer graphene growth is facilitated by a copper foil placed nearby Pt/Ti/SiO2 substrate and by a high filament temperature in the HFCVD reactor. Monolayer graphene grows only when no copper foil is placed near the Pt/Ti/SiO2 substrate at a low filament temperature. The approach paves a novel pathway towards the layer‐controlled growth of graphene on Pt/Ti/SiO2 substrates by HFCVD for frontier applications. [ABSTRACT FROM AUTHOR]

Here, we have studied the phase transition and magneto-electric properties of a 70 wt. % Pb(Fe0.5Nb0.5)O3–30 wt. % Co0.6Zn0.4Fe1.7Mn0.3O4 (70 wt. % PFN–30 wt. % CZFMO) multiferroic composite that exhibits a maximum magneto-electric (ME) coefficient of 26.78 mV/cm Oe at room temperature. Raman analysis confirms the formation of composite and development of strain with the shifting of Raman modes. The local symmetry breaking of end members of the composite is observed by the splitting of Raman modes. The first-order derivative of magnetization with temperature (dM/dT vs T) shows anomalies across 140 K due to the PFN phase, whereas the anomaly around 250 K is due to the spin glass transition of the CZFMO phase. The magnetization vs magnetic field (M–H) study at different temperatures reveals the existence of superparamagnetic behavior above 300 K. The temperature-dependent dielectric behavior of the composite shows an anomaly around ferroelectric phase transition (Tm) for the PFN phase along with the broad relaxation peak arising due to the CZFMO phase. The linear behavior of magnetocapacitance (MD%) with the square of magnetization (M2) suggests the existence of biquadratic ME coupling. The ME study on the composite suggests the existence of both direct and converse ME effects. [ABSTRACT FROM AUTHOR]

2D tin chalcogenides are promising materials for thin-film solar cells due to their excellent characteristics. SnS1−xSex alloy films have garnered attention from researchers over the last few decades due to their tunable physical features. Here, we report the successful preparation of SnS1−xSex powder using a temperature-assisted mechanochemical process and their subsequent deposition on glass substrates via thermal evaporation. X-ray diffraction (XRD) and Raman spectroscopy were used to extensively analyse SnS1−xSex thin films, elucidating their structural characteristics. The presence of a ternary alloy has been verified by both energy dispersive X-ray spectroscopy (EDAX) and X-ray photoelectron spectroscopy (XPS). The absorption spectrum shows that TSSe thin films have great potential for absorbing a wide range of visible light. Hall measurement revealed that n-type TSSe thin films have shown great promise with the highest hall mobility of up to 16.7 cm2 V−1 s−1. Our study demonstrates that TSSe has excellent potential as a 2D material for cutting-edge photovoltaic applications. [ABSTRACT FROM AUTHOR]

Multiferroic materials capable of robust magnetoelectric coupling at room temperature are currently being explored for their possible multifunctional device applications. Highly (100)-oriented Pb(Fe0.5Ta0.5)x(Zr0.53Ti0.47)1−x (PZTFTx) thin films (x = 0.2 and 0.3) with a thickness of about 300 nm were grown on La0.67Sr0.33CoO3 (LSCO)-buffered MgO 100-oriented substrates via the pulsed laser deposition method. An analysis of their X-ray diffraction patterns suggests the stabilization of the orthorhombic phase in the thin films at room temperature. Dielectric spectroscopic measurements of the metal–insulator–metal (Pt/PZTFTx/LSCO) thin-film capacitors as a function of temperature revealed a diffuse ferroelectric-to-paraelectric phase transition around Tm ~520 and 560 K for the x = 0.2 and 0.3 thin films, respectively. Well-saturated electrical hysteresis loops with large remanent (Pr) and saturation (Ps) polarizations were observed in these capacitors, which indicates the establishment of intrinsic ferroelectric ordering in the thin films at room temperature. These thin films retained ferromagnetic/ferrimagnetic ordering up to 300 K and showed saturation magnetization values of 8.3 (x = 0.2) and 6.1 (x = 0.3) emu/cm3 at room temperature. The magnetoelectric coupling constants of 2040 mV/cmOe (x = 0.2) and 850 mV/cmOe (x = 0.3), respectively, were obtained at an in-plane bias field at room temperature. The present study demonstrates that PZTFTx thin films are multiferroic at room temperature with large magnetoelectric couplings, and these materials may be suitable for use in magnetic sensors and spintronic device applications. [ABSTRACT FROM AUTHOR]

In this work, we report a systematic study of complex La3+ and Sc3+ doped lead zirconate titanate ceramics with the stoichiometric formula (PbZr0.53Ti0.47)0.90 (LaxSc1−x)0.10O3−δ for x = 0.2, 0.4, 0.6, and 0.8 denoted as PLZTS2, PLZTS4, PLZTS6, and PLZTS8, respectively (abbreviated as PLZTS10x), synthesized using the solid-state reaction method. We carried out dielectric measurements on Ag/PLZTS10x/Ag metal–ferroelectric–metal capacitors as a function of temperature (100–650 K) and frequency (102–106 Hz). Upon increasing La3+ concentration, the dielectric constant was found to be increased up to x = 0.6 and attained the highest value of ∼1800 at room temperature, and consequently, the highest saturation polarization was observed. The relaxor behavior of PLZTS8 can be attributed to the polar nano regions created in the materials. A recoverable energy density of ∼1162 mJ/cm3 with an excellent efficiency of ∼79% was achieved under an applied electric field of 97 kV/cm. The demonstrated high dielectric constant (ɛ′), spontaneous polarization (Ps), and energy density make these bulk materials promising for ferroelectric memory and energy-storage applications. [ABSTRACT FROM AUTHOR]

Alloy engineering are efficient methods to improve the physical properties of two‐dimensional (2D) material‐based photovoltaic application. Tin chalcogenide belonging to layered structured semiconducting family has been a significant compound due to its outstanding characteristics. Tin selenide (SnSe) is known as promising layered compound to develop 2D materials for optoelectronic devices. The current study focused onto the effect of tin sulfoselenide (SnSSe) alloy engineering on the structural, morphological, optical, and electrical characteristics. X‐ray Diffraction (XRD) confirmed that SnSSe and SnSe are exist in the orthorhombic crystal structure phase without other secondary phases, with the preferred high‐intensity peak along (111) oriented plane. Raman spectra was reported to give information about the vibrational characteristics of the compounds. The presence of Sulfur ion in SnSSe was further confirmed by Energy Dispersive X‐ray Spectroscopy (EDAX) and X‐ray Photoelectron Spectroscopy (XPS) analysis. Bandgap energy (Eg) has been analysed by Tauc's plot and the derivative of transmittance spectra. According to both sets of analyses, the bandgap of the SnSSe thin film is considerably smaller than that of the SnSe thin film. Hall measurements indicated that SnSSe exhibits the higher hole mobility. The present work's results offer useful insight into the prospective device applications of two‐dimensional alloy materials. [ABSTRACT FROM AUTHOR]