Revealing The Degradation Mechanism of (Sr,Ca)AlSiN₃:Eu²⁺ Phosphor Aged Under Thermal-Moisture-Sulfur Conditions: A Combined Experimental and Ab Initio Study

MAlSiN₃:Eu²⁺ (M = Ca, Sr) is commonly used in high-power phosphor-converted white-light-emitting diodes and laser diodes to promote their color-rendering index. However, the wide application of this phosphor is limited by the degradation of its luminescent properties in high-temperature, high-humidity, and high-sulfur...

First-Principles Study on the Elastic Mechanical Properties and Anisotropies of Gold–Copper Intermetallic Compounds

In this study, first-principles calculations were utilized to investigate the lattice constants, elastic constants, and mechanical properties of gold–copper (Au–Cu) intermetallic compounds (IMCs), including AuCu3, AuCu, and Au3Cu. We also verified the direction dependence of the Young’s modulus, shear modulus, and Poisson’s ratio of the...

Hydrogenated Boron Phosphide with the excellent tunability of electronic properties and Current-Voltage responses

Combining the first principles calculations and the non-equilibrium Green’s function formalisms, we decipher the structural, electronic, and transport properties of boron phosphide (BP) with hydrogenation. Hydrogenated BP monolayer is an indirect semiconductor with a wide-bandgap of 3.76 eV that is favorable in power devices. We find that the...

Electron-Irradiation-Induced Degradation of Transfer Characteristics in Super-Junction VDMOSFET

High electric-field stress is an effective solution to the recovery of irradiated devices. In this paper, the dependence of the recovery level on the magnitude of gate voltage and duration is investigated. Compared with the scheme of high gate-bias voltage with a short stress time, the transfer characteristics are significantly recovered by...

Strain-engineered S-HfSe₂ monolayer as a promising gas sensor for detecting NH₃: A first-principles study

The development of high-performance gas sensing materials is one of the development trends of new gas sensor technology. In this work, in order to predict the gas-sensitive characteristics of HfSe₂ and its potential as a gas-sensitive material, the interactions of nonmetallic element (O, S, Te) doped HfSe₂ monolayer and...

Solder joint reliability risk estimation by AI-assisted simulation framework with genetic algorithm to optimize the initial parameters for AI models

Solder joint fatigue is one of the critical failure modes in ball-grid array packaging. Because the reliability test is time-consuming and geometrical/material nonlinearities are required for the physics-driven model, the AI-assisted simulation framework is developed to establish the risk estimation capability against the design and process...

The Mechanical Properties and Elastic Anisotropy of η’-Cu6Sn5 and Cu3Sn Intermetallic Compounds

Full intermetallic compound (IMC) solder joints present fascinating advantages in high-temperature applications. In this study, the mechanical properties and elastic anisotropy of η’-Cu6Sn5 and Cu3Sn intermetallic compounds were investigated using first-principles calculations. The values of single-crystal elastic constants, the elastic (E),...

A hybrid mimetic spectral element method for three-dimensional linear elasticity problems

We introduce a domain decomposition structure-preserving method based on a hybrid mimetic spectral element method for three-dimensional linear elasticity problems in curvilinear conforming structured meshes. The method is an equilibrium method which satisfies pointwise equilibrium of forces. The domain decomposition is established through...

Effective Approaches of Improving the Performance of Chalcogenide Solid Electrolytes for All-Solid-State Sodium-Ion Batteries

All-solid-state sodium-ion batteries (SIBs) possess the advantages of rich resources, low price, and high security, which are one of the best alternatives for large-scale energy storage systems in the future. Also, the chalcogenide solid electrolytes (CSEs) of SIBs have the characteristics of excellent room-temperature ionic conductivity (10...

First principles study of gas molecules adsorption on monolayered β-SnSe

For the purpose of exploring the application of two-dimensional (2D) material in the field of gas sensors, the adsorption properties of gas molecules, CO, CO₂, CH₂O, O₂, NO₂, and SO2 on the surface of monolayered tin selenium in β phase (β-SnSe) has been researched by first principles calculation...

First-principles investigation of the adsorption behaviors of CH ₂ O on BN, AlN, GaN, InN, BP, and P monolayers

CH ₂ O is a common toxic gas molecule that can cause asthma and dermatitis in humans. In this study the adsorption behaviors of the CH ₂ O adsorbed on the boron nitride (BN), aluminum nitride (AlN), gallium nitride (GaN), indium nitride (InN), boron phosphide (BP), and phosphorus (P) monolayers were investigated using...

Uptake of heavy metal ions in layered double hydroxides and applications in cementitious materials: Experimental evidence and first-principle study

The uptake mechanism of heavy metal ions in layered double hydroxides (LDHs) is investigated in this paper via solid-solution exchange experiments and first principle study. The uptake capacities of C-LDHs for heavy metal ions from solutions are experimentally investigated and the structures of LDHs doped with various heavy metal ions are...

Repairing surface defects of metal parts by groove machining and wire + arc based filling

An approach to repairing surface defects of metal parts is proposed, which includes a combined application of (i) groove machining, (ii) wire and arc additive manufacturing (WAAM), and (iii) finishing machining. The completed analysis revealed that (i) the inclination angle of the groove to be machined is strongly influenced by the...

The effects of graphene stacking on the performance of methane sensor: A first-principles study on the adsorption, band gap and doping of graphene

The effects of graphene stacking are investigated by comparing the results of methane adsorption energy, electronic performance, and the doping feasibility of five dopants (i.e., B, N, Al, Si, and P) via first-principles theory. Both zigzag and armchair graphenes are considered. It is found that the zigzag graphene with Bernal stacking has...

Influence of Pressure on the Mechanical and Electronic Properties of Wurtzite and Zinc-Blende GaN Crystals

The mechanical and electronic properties of two GaN crystals, wurtzite and zinc-blende GaN, under various hydrostatic pressures were investigated using first principles calculations. The results show that the lattice constants of the two GaN crystals calculated in this study are close to previous experimental results, and the two GaN crystals...

Promoting sensitivity and selectivity of HCHO sensor based on strained InP₃ monolayer: A DFT study

Sensitive materials for formaldehyde (HCHO) sensor need high sensitivity and selectivity. The research on two dimensional (2D) sensitive material is growing, and most studies focus on the pristine or modified graphene. So it is essential to introduce other 2D materials into HCHO gas sensor. In this report, the adsorption behaviors of organic...

Mechanical, thermodynamic and electronic properties of wurtzite and zinc-blende GaN crystals

For the limitation of experimental methods in crystal characterization, in this study, the mechanical, thermodynamic and electronic properties of wurtzite and zinc-blende GaN crystals were investigated by first-principles calculations based on density functional theory. Firstly, bulk moduli, shear moduli, elastic moduli and Poisson's ratios...