First-Principles Analysis on the Catalytic Role of Additives in Low-Temperature Synthesis of Transition Metal Diborides Using Nanolaminates

Abstract

Carbon is known to significantly accelerate the formation reaction of zirconium diboride in reactive nanolaminates, although the detailed mechanism remains unclear. Here we investigate the catalytic effect of both C and N on the synthesis of ZrB2 using a first-principles theoretical approach. We show that the strong interactions of C and N with Zr at the B/Zr interfaces of the nanolaminate enhance the solid-state amorphization of the Zr lattice. Amorphization of the Zr, in turn, accelerates intermixing of the constituent layers of the reactive nanolaminate. On the basis of these results we propose that the addition of elements with strong binding energies to transition metals may facilitate low-temperature synthesis of transition metal diborides using reactive nanolaminates.

New Insight into the Effect of Alloying Elements on Elastic Behavior, Hardness, and Thermodynamic Properties of Ru2B3

“…In particular, the value of B / G ratio of alloying elements of W (1.57) and Re (1.56) is smaller than that of other alloying elements. This trend is similar to the G and E …”

“…In particular, the value of B/G ratio of alloying elements of W (1.57) and Re (1.56) is smaller than that of other alloying elements. This trend is similar to the G and E. 38 The Vickers hardness of Ru 2 B 3 in this article is examined by Chen et al model. 39 The calculated theoretical Vickers hardness of Ru 2 B 3 is 20.3 GPa.…”

Defects Mediated Corrosion in Graphene Coating Layer

“…The presence of the doping elements further reduces the strength, ductility, and elastic stiffness of graphene. S results in a larger reduction in strength than O because of the relatively stronger bonding of O–C, indicated by the formation energies in Figure , which retains the bonding network under strain . We take the sites 1 and 3 to represent the interstitial site at the pentagon and heptagon sites.…”

“…Figure 6 shows the stress− strain curves of six graphene models, including perfect graphene, graphene with grain boundaries, and graphene with 5, which retains the bonding network under strain. 44 We take the sites 1 and 3 to represent the interstitial site at the pentagon and heptagon sites. The interstitial atom at site 3 has a larger effect on the mechanical than that at site 1, which is consistent with the trend of the formation energy in Figure 5vacancy at the pentagon site causes less disruption to the carbon network when graphene is deformed because of a relatively smaller void size created by the pentagon vacancy (5−6−6 ring) than the heptagon vacancy (6−6−7 ring).…”

Two‐step pyrolysis preparation of co‐doped porous g‐C3N4 with Co–N coordination bond for dye efficient degradation driven by visible light

“…Metal doping is achieved by inserting said metal into the g-C 3 N 4 framework. Specifically, Lee et al 21 reported that transition metal cations (such as Fe 3+ , Mn 3+ , Co 3+ , Ni 3+ , and Cu 2+ ) were incorporated into the framework of g-C 3 N 4 , and results showed that the doped material extends its light absorption to longer wavelengths and reduces the recombination efficiency of photogenerated carriers. Zhao et al 22 used melamine, potassium chloride, and sodium chloride as precursors and prepared the tunable K Na co-doped g-C 3 N 4 by molten salt method.…”