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 electronic properties are dependent of the stacking orders and the binding strength of the AA-, AB-, and AE-stacked patterns are strongest in the investigated configurations. Under the external E-field, the bandgaps of hydrogenated BP bilayer show a quasi-parabolic function and a feature of the semiconductor-metallic transition. Besides, when we apply a tensile strain on hydrogenated BP bilayer, its bandgap linearly decreases with the increasing of the strain strength along the zigzag and armchair directions. The strain energies further confirm that hydrogenated BP has an excellent characteristic of elastic deformation, being independent of the stacking orders and strain orientation. The transport calculations exhibit various responses to the different two-probe configurations, which indicates that hydrogenated BP possesses the feature of transmission anisotropy. Owing to the nontrivial tunability and transport feature, the hydrogenated BP materials may have tremendous prospects to be applied in micro-/nano-devices with high consumption.@en

The authors regret that one of the affiliations (affiliation f) was incorrectly omitted in the original manuscript. The corrected list of affiliations is as shown below. The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers.

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Nano-metal sintering has been proven to be a promising die attachment technology for power electronics packaging in the high-end application. Compared with nano silver technology, it is believed that copper-based sintering technology has better cost and performance superiority, and thus has more potential to be utilized in the industry in the future. However, most of the current developed nano copper sintering material and technology shows bad performance with high sintering energy input. In this study, a novel nano-copper based paste has been developed with excellent process ability (sinterable below 280°C for 10 min with low pressure assisted) and good material property (over 40 MPa shear strength), which turns out to be suitable for the state-of-the-art packaging process. Then the material was applied into a SiC power module packaging scenario which shows comparable performance as silver sintering. The whole process only consumed less than 0.5h for each batch, which indicates that the copper sintering technology has great potential for the packaging application in high power situation.@en

At present, non-equilibrium thermodynamics is an important theory and method for studying the phenomenon of small scales. In this work, by studying the temperature changes of PN junctions under different voltage conditions and doping concentrations, the micro-scale semiconductor materials PN junctions in non-equilibrium thermodynamics and thermal phenomena are researched. It is found that under the effect of lower voltage, the temperature of the PN junction will first decrease and then increase, and as the voltage increases, this phenomenon will gradually disappear. This shows that under certain voltage conditions, the phenomenon of unbalanced junction temperature of the PN junction exists, which will provide a huge impetus for the development of the reliability of solar cells, light-emitting diodes, high-frequency devices, sensors and measurement methods.

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As the concentration of acetone (C₃H₆O) in exhaled gas of diabetics is significantly higher than that of healthy people. Here, the sensing performance of X doped MoSe₂ (X–MoSe₂, X = Ti, Ni and Cu) for acetone is studied theoretically. It is found that Ti–MoSe₂ shows absolute advantages in both adsorption energy and charge transfer. Additionally, the changes of bandgap for C₃H₆O/Ti–MoSe₂ in the adsorption process are the largest in all adsorption systems, indicating it will produce the largest electrical signal that can be detected. Besides, the co-adsorption system (consisting of C₃H₆O, H₂O, CO₂, N₂ and O₂) will be more stable after O₂ is removed and the adsorption site occupied by acetone restricts the contact of other disturbing gases with Ti–MoSe₂. Importantly, comparing with the reported acetone sensing materials ((110) face of SnO₂, (MgO)₁₂-graphene and oxygen-plasma-treated ZnO (ZnO–O)), Ti–MoSe₂ demonstrates its superiority in terms of the absolute value of charge transfer (0.37 e) and adsorption energy (2.42 eV). All these results show that Ti–MoSe₂ is expected to become the reliable sensing material for acetone and has enormous potential for the application in noninvasive and rapid detection of type-1 diabetes.

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As an outstanding corrosion inhibitor for copper, the adsorption behavior of benzotriazole on copper nano cluster has been investigated and compared with copper (111), (100) and (110) surfaces by means of density functional theory (DFT) calculations. Calculations reveal that benzotriazole has chemical adsorption on different copper surfaces and copper nano cluster when its N2-N3 bond is placed down on them. Also, the adsorption energy and closest interatomic distance show strong dependence on the surface structure, which indicates its ability to passivate the reactive under-coordinated surface sites. Relatively strong chemical bond between the copper cluster and the adsorbate is found to form. The chemisorption mechanism and the local structure of benzotriazole on copper surfaces and nano cluster are also discussed and presented.@en

Nano-metal sintering is a promising technology for the next generation of semiconductor packaging due to its positive effect on reliability enhancement. Compared with the silver sintering, copper-based sintering technique has more potential to be applied in die attachment field as its superiorities on lower cost, higher melting temperature without electromigration. In this study, Taguchi method is applied to study and analyze the effect of nano-/micro- particle ratio on sintering properties. Sintering temperature is also taken into account since it depends on the particle size a lot. The results show that both sintering temperature and nano-micro- ratio play significant role on influencing shear strength. The best combination is 300 nm with 1 um mixing (1:1) with over 35 MPa shear strength with 300°C sintering temperature. The fracture surface result shows that the crack propagated in the sintering body. Furthermore, the cross-section inspection reveals dense bonding and clearly sintering necking, and the porosity is lower than 12%. 227.8 W/m*K thermal conductivity and 6.0 uΩ·cm electrical resistivity are measured for the sample, which indicates the great potential for the packaging application in high power situation.@en

Exploring effective disinfection methods and understanding their mechanisms on the new coronavirus is becoming more active due to the outbreak of novel coronavirus pneumonia (COVID-19) caused by severe acute respiratory coronavirus 2 (SARS-CoV-2). By combining molecular dynamics and first-principles calculations, we investigate the interaction mechanism of chemical agents with 3CL hydrolase of SARS-CoV-2. The radial distribution functions indicate that the biocidal ingredients are sensitive to the unsaturated oxygen atoms of 3CL hydrolase and their interactions remarkably depend on the concentration of the biocidal ingredients. Besides, we find that the adsorption performance of the active ingredients for the unsaturated oxygen atoms is superior to other styles of atoms. These computational results not only decipher the inactivation mechanism of chemical agents against SARS-CoV-2 from the molecule-level perspective, but also provide a theoretical basis for the development and application of new chemical methods with a high disinfection efficiency.

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