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The interface microzone characteristics determine the thermophysical properties of diamond/Cu composites, while the mechanisms of interface formation and heat transport still need to be revealed. Here, diamond/Cu-B composites with different boron content were prepared by vacuum pressure infiltration. Diamond/Cu-B composites up to 694 W/(mK) were obtained. The interfacial carbides formation process and the enhancement mechanisms of interfacial heat conduction in diamond/Cu-B composites were studied by HRTEM and first-principles calculations. It is demonstrated that boron can diffuse toward the interface region with an energy barrier of 0.87 eV, and these elements are energetically favorable to form the B4C phase. The calculation of the phonon spectrum proves that the B4C phonon spectrum is distributed in the range of the copper and diamond phonon spectrum. The overlapping of phonon spectra and the dentate structure together enhance the interface phononic transport efficiency, thereby improving the interface thermal conductance. [ABSTRACT FROM AUTHOR]

Vanadium-based alloys have excellent reversible hydrogen storage properties, and the empirical lattice parameter law is often used experimentally for optimization of alloy composition. To reveal the underlying mechanisms, hydrogen storage properties and local environmental effect of H dissolution in V–Fe–Ti alloys were studied experimentally and computationally. The experimental results show that adding Fe and Ti has opposite effects on the hydrogen storage capacity of alloys, and (V 85 Fe 15) 100- x Ti x alloys with 20%Ti addition can exhibit the best performance, which satisfies the empirical lattice parameter law. Furthermore, atomic-scale simulations have demonstrated that H dissolution is affected by its dissolution location and surrounding alloy species through comparing the stability, electronic structure, and bonding characteristics of different V-based alloys. Besides, the correlation analyses of different factors with the hydrogen dissolution energy verify the rationality of the empirical law. Our findings provide useful insight into the rational design of Fe–V–Ti alloys for high-capacity hydrogen storage. [Display omitted] • V–Fe–Ti alloys with the 20%Ti addition exhibit the best performance in experiments. • The empirical lattice parameter law was interpreted by experiments and DFT. • The interaction mechanism of H with V–Fe–Ti alloys was revealed theoretically. • The correlation of varied factors with hydrogen dissolution energy was analyzed. [ABSTRACT FROM AUTHOR]