Surface roughness hydrogen termination

In summary, oxide layers on silicon surfaces are chemically dissolved in HF leading to the formation of an atomically rough hydrogen-terminated surface. At (111) surfaces, relatively large domains of ideally terminated Si(lll) H (1x1) can be formed by subsequent immersion in buffered HF of pH 8-9. The smoothening process is controlled by the rate of step recession at the surface. 

The substitution of the H(D)-termination by the D+CH ) in the solution at the extreme cathodic potential was confirmed from the above-mentioned results[24]. The hydrogen evolution at the B-doped diamond electrode does proceed via the carbon radical formation at the surface, as shown in eq.(7.l). However, it is difficult to estimate the surface concentration of the substituted sites due to the lack of the inspected correlation between the yield obtained and the surface concentration of the surface hydrogen. The absorption of atomic hydrogen or deuterium in the subsurface and bulk of the B-doped diamond may also confuse this problem [25, 26]. Since the surface roughness affects the yield, TOF ESD measurements at epitaxially grown B-doped diamond single crystalline electrodes [27, 28] are desirable in order to estimate the kinetics of the cathodic substitution of the surface hydrogen. 

Although the Mo-terminated (0001) surface model provides important insights into the benzene hydrogenation on M02C, it may not correctly reflect the whole story of the reaction. The MCNPs, as opposed to the bulk form, are usually roughly spherical amorphous particles [49]. Since the interaction of the surface species with the catalyst (or adsorption) is known as a local phenomenon, the topology of the active site on MCNPs may be essential for the reactions. Also, the quanmm size effect of the MCNPs should not be neglected. 

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