Cassidymaldonado0998

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19 mg/g, which has not been previously reported.In the current research, p-type Si/n-type nanocrystalline FeSi₂ heterojunctions were fabricated at room temperature with an argon pressure of 2.66×10-1 Pa by means of the utilization of a radiofrequency magnetron sputtering technique. These heterojunctions were studied for the carrier transportation mechanism and near-infrared (NIR) light detection at various temperatures ranging from 300 K down to 150 K. At 300 K, the fabricated heterojunctions displayed a typical rectifying action together with substantial leakage current. At 150 K, the leakage current was clearly reduced by greater than four orders of magnitude. The value of the ideality factor (n) at 300 K was computed to be 1.87 and this was nearly constant under temperatures ranging from 300 down to 260 K. This implies that a recombination process was predominant. At temperatures lower than 250 K, the value of n was found to be more than 2. These results demonstrated that the carrier transportation mechanism was governed by a tunnelling process. A weak response for the irradiation of NIR light was observed at 300 K. At 150 K, the ratio of the photocurrent to the dark current evidently increased by more than two orders of magnitude. The detectivity at 150 K was 4.84×1010 cm Hz1/2 W-1 at zero bias voltage, which was clearly improved as compared to that at 300 K.In this research, β-FeSi₂ thin films were manufactured onto Si(111) wafer substrates through the usage of radio-frequency magnetron sputtering (RFMS) method at 2.66 × 10-1 Pa of sputtering pressure. The substrate temperatures were varied at 500 °C, 560 °C, and 600 °C. The Raman lines of the β-FeSi₂ fabricated at 500 °C revealed the peaks at the positions of ~174 cm-1, ~189 cm-1, ~199 cm-1, ~243 cm-1, ~278 cm-1, and ~334 cm-1. For the higher substrate temperatures of 560 °C and 600 °C, the Raman peaks of ~189 cm-1, ~243 cm-1, and ~278 cm-1 were shifted toward higher Raman positions. The surface view of the films was observed with several grains over the β-FeSi₂ film surface at all substrate temperatures. The average grain size of the films for the samples deposited at 500 °C and 560 °C was in the range of 28 to 30 nm, where the size was enlarged to 36 nm at 600 °C of substrate temperature. The root mean square roughness were 10.19 nm, 10.84 nm, and 13.67 nm for the β-FeSi₂ film surface prepared at the substrate temperatures of 500 °C, 560 °C, and 600 °C, respectively. The contact angle (CA) values were 99.25°, 99.80°, and 102.00° for the created samples at 500 °C, 560 °C, and 600 °C, respectively. selleck chemicals As the acquired CA values, all β-FeSi₂ samples exhibited a hydrophobic property with CA in the range of 90° to 150°. Consequently, the produced β-FeSi₂ film surface employing the RFMS method indicated a potential to be employed in a hydrophobic coating application.We designed novel thermally activated delayed fluorescence (TADF) host molecules for blue electrophosphorescence by combining the electron acceptor benzimidazole (BI) unit and the electron donor acridine derivatives into a single molecular unit based on density functional theory (DFT). We obtained the energies of the first singlet (S1) and the first triplet (T1) excited states of the TADF materials by performing DFT and time-dependent DFT (TD-DFT) calculations to the ground state using dependence on charge transfer amounts for the optimal Hartree-Fock percentage in the exchange-correlation of TD-DFT. Using DFT and TD-DFT calculations, the large separation between the HOMO and LUMO caused a small difference in energy (ΔEST) between the S1 and T1 states. The host molecules retained high triplet energy and showed great potential for use in blue phosphorescent organic light-emitting diodes. The results showed that these molecules are promising TADF host materials because they have a low barrier to hole and electron injection, balanced charge transport for both holes and electrons, and a small ΔEST.As multifunctional materials, rare-earth hexaborides (RB6) display many interesting physical properties such as optical absorption, magnetic and thermionic emission. With the wide application of rare earth hexaboride and the continuous extension of its research fields, researchers have studied the synthesis of multi-rare earth hexaboride nano-powders and their thermal emission and light absorption properties. In the present work, ternary Single-phase LaxPr1-xB6 submicron powders are successfully synthesized using a solid-state reaction, in which lanthanum chloride (LaCl₃) and praseodymium chloride (PrCl₃) are used as rare-earth source and NaBH₄ as the boron source under continuous vacuum conditions. The reaction temperature is 1150 °C and the holding time is 2 h. The Pr doping effects on crystal structure, grain morphology, and optical absorption properties were investigated using X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM) and ultraviolet-vis absorptionf LaB6 in the visible region after doping Pr is related to the decrease of kinetic energy of electrons near the Fermi plane. X-ray photoelectron spectroscopy (XPS) analysis shows that the La and Pr exist in the type of La3+ and Pr3+ in LaxPr1-xB6. Therefore, it exists as an efficient optical absorption material. The LaxPr1-xB6 should open up a new route to extend the optical applications of rare-earth hexaborides.The friction stir welding (FSW) parameters were designed in this study by orthogonal experimental method. The microstructure, mechanical properties and corrosion behavior of corresponding FSW joints of 5083 aluminium alloy (AA5083) were also investigated. Scanning Kelvin probe force microscopy (SKPFM) was employed to study local potential differences on the FSW joint. Results showed that the welding parameters greatly influenced the FSW joint properties of the AA5083. The ratio of rotation speed to welding speed (n/v) mainly affected the mechanical properties of the joint. The tensile strength for the joint was reduced when welded with too large or too small n/v. The hardness of all FSW joints was characterized with similar 'W-shaped,' and minimum hardness value appeared on advancing side of the heat affected zone. Different heat input and agitation intensity caused heterogeneous microstructure for the AA5083 FSW joint, which led to differences in passivation properties of weld nugget zone, thermo-mechanically affected zone and heat-affected zone.