In virtue of the first-principle calculations, the hydrogen storage behavior in several metal decorated graphyne was investigated. It is found that the hydrogen storage capacity can be as large as 18.6, 10.5, 9.9 and 9.5 wt% with average adsorption energy of about −0.27, −0.36, −0.76 and −0.70 eV/H2 for Li, Ca, Sc, Ti decorated graphyne, respectively. The results suggest potential candidates for hydrogen storage at ambient condition. The adsorption mechanism for H2 on metal coated graphyne was mainly attributed to the polarization induced by electrostatic field of metal atoms on graphyne and the hybridization between the metal atoms and hydrogen molecules. Furthermore, the formation of super-molecules of hydrogen can enhance the adsorption energy.Highlights► We studied Li, Ca, Sc, Ti decorated graphyne as a medium for hydrogen storage. ► The hydrogen storage capacity can be as large as 18.6, 10.5, 9.9 and 9.5 wt%. ► The average adsorption energy is about −0.27, −0.36, −0.76 and −0.70 eV/H2.

The hydrogen adsorption on Ti-coated graphene under an external electric field was investigated through the first-principle calculations. Strikingly, the external electric field not only stabilizes the dispersion of Ti atoms on graphene against aggregating, but also enhances the hydrogen storage capacity. Furthermore, our calculations revealed that the external electric field can effectively tune the hydrogen adsorption energy, providing an effective approach for the hydrogen adsorption and desorption for hydrogen storage applications.Highlights► The dispersive Ti atoms on graphene are against aggregation with F > −0.006 au. ► The external electric field can effectively tune the hydrogen adsorption energies. ► The additional hydrogen molecules can be adsorbed with F > −0.01 au.

The charge trap flash memory cells incorporating high-k ZrO2/Al2O3 nanolaminate as charge trapping layers and amorphous Al2O3 as tunneling and blocking layers were prepared, investigated and optimized. The interfaces between ZrO2/Al2O3 nanolaminate play an important role in the charge storage characteristics. With increasing number of the interfaces in the charge trapping layer, the memory window increases first and then decreases due to electrostatic repulsion between the trapped electrons. A satisfactory retention performance was observed in the optimized cell structure, which was attributed to the deep quantum wells between the ZrO2/Al2O3 nanolaminate.Graphical abstractHighlights► Nanolaminate-based charge trap flash memory cells incorporating a high-k ZrO2/Al2O3 nanolaminate as charge trapping layer and amorphous Al2O3 as tunneling and blocking layer. ► It is proposed that the charges are trapped by the ZrO2/Al2O3 interfaces. ► Excellent retention performance was attributed to appropriate distance of neighboring interfaces and deep quantum well as identified by measured valence band offsets and electron energy loss spectrum.

We report non-saturating linear magnetoresistance (LMR) in silver-poor composite thin films of Ag10Ge15Te75 (AGT). The LMR increases with decreasing temperature and reaches a value of 110% at 200 K under a magnetic field of 70 kOe. The observed magnetoresistance is proportional to carrier mobility due to identical temperature dependencies. The microstructures of AGT films annealed at different temperature are investigated by TEM observations. The observed LMR effect is resulting from the inhomogeneous distribution of conductivity caused by highly conductive Ag2Te and GeTe4 precipitates, which generate a current distortion in the surrounding amorphous silver-poor Ag–Ge–Te matrix.Highlights► The linear magnetoresistance has been observed in silver-deficient chalcogenides. ► The observed magnetoresistance is linearly proportional to carrier mobility due to the identical temperature dependencies. ► The inhomogeneous distribution of Ag2Te observed by TEM caused the LMR effect.

On the basis of first-principles density functional calculations, we predict that Li-decorated graphyne can serve as a promising candidate for hydrogen storage, with a largest storage capacity of 18.6 wt %. The average adsorption energy of hydrogen is about −0.27 eV/H2, indicating that the doped system is an ideal hydrogen storage material at ambient conditions. It is proposed that the polarization mechanism, which stems from the electric field induced by the ionic Li coated on the graphyne, plays a key role in the adsorption of H2 molecules. Furthermore, the formation of the hydrogen–hydrogen complex also stabilizes the adopted hydrogen molecules.

The structural and optical characterizations of titania incorporated with alumina nanocrystals have been presented in this paper and the films exhibit excellent properties like low current density, small hysteresis as well as high photoluminescence quantum yields of about 361 nm. These properties are promising for the applications in future electronic devices.

The room-temperature microstructural evolution of 18 μm thick electroplated copper deposits was investigated by cross-sectional focused ion-beam microscopy. The fraction of transformed volume as a function of annealing time was measured. The transformation was found to start and nucleate from the bottom of the foils and then propagate towards the free surfaces. Based on differential scanning calorimetry results, the activation energy for grain growth is 0.85 eV atom−1. The mechanism of the grain growth is also discussed.