The interaction of water with oxygen-modified ZrC(100) surfaces

Atomistic simulations of surface reactions in ultra-high-temperature ceramics: O2, H2O and CO adsorption and dissociation on ZrBZhang1, Sanvito2 2021Applied Surface Science6000View full textAdd to dashboardCite

“…Thus, we conclude that on (0001) Zr the (a1) path, with the low activation energy of 0.09 eV, is the most kinetically favourable and dominates the dissociation of H 2 O into the OH and H groups. Notably, this is the same dissociation reaction experimentally observed for H 2 O on ZrC(001) [9]. The relatively high barrier for OH deprotonation, together with the fact that the energy of fully dissociated configuration is higher than the one in which the OH group remains intact on the surface, make this decomposition channel unlikely.…”

“…Furthermore, at an oxygen-modified ZrC(100) surface, the dissociation of H 2 O into hydroxyl (OH) and atomic O species was discovered by a combination of ultraviolet photoelectron spectroscopy (UPS) and XPS measurements. [9] As an alternative to experiments, atomistic simulations provide a powerful tool to explore surface reactions in more details. For example, by using density functional theory (DFT) calculations, Sayós et al [10] proposed that the adsorption of atomic O on the ZrB 2 (0001) surface takes place predominantly at the hollow and B-B bridge sites.…”

Photoelectron Spectroscopy Study of the Oxidation of TiC(100)

“…In addition, we also found that the reactivity of the ZrC(100) surface is much enhanced when the surface is covered with the ZrO-like layer; the ZrC(100) surface is inert towards H 2 O adsorption while H 2 O adsorbs dissociatively on the surface covered by the ZrOlike layer, to form hydroxyl (OH) and atomic O species. 11) These results suggest that the oxidative treatment forming a suboxide layer is essential to reform the TMC surfaces, and thus further study of the oxidation process of other TMC surfaces is urgently called for.…”

Synthesis of zirconium carbide (ZrC) nanoparticles covered with graphitic “windows” by pulsed plasma in liquid

“…However, the poor oxidation resistance of ZrC when produced as nanometer-sized particle restricts these above applications. [5][6][7][8] Since 1993, 9 graphitic carbon-coated nanoparticles [10][11][12][13][14] have attracted a great deal of research globally, most theorizing that the carbon shell in these structures would be able to protect the inner core materials, thus improving anti-oxidation of ZrC nanoparticles in our case. Although some works on the synthesis of ZrC nanoparticles composed of such a structure by arc burning, mechanical alloying or the co-reduction-carburization method exist, [15][16][17] these methods have failed to avoid thick carbon coatings, unwanted carbonaceous debris or size growth, all of which debilitate the light absorption and emissivity rate of the particles.…”