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Al-doped zinc oxide (AZO) thin films containing trace Ag nanoparticles (Ag/Zn = 0-0.15 at.%) were prepared by the sol-gel process. It was found that the doping of Ag nanoparticles resulted in the significant sintering of AZO grains and further led to the enhancement of conductivity. From the analysis of surface morphology, it was suggested that the presence of Ag nanoparticles might be helpful for the sintering of AZO grains at lower temperatures, which increased the grain size (or decreased the grain boundaries) and led to the decrease in electrical resistivity. By optimizing the heat treatment conditions, the electrical resistivity of AZO thin films containing 0.1 at.% Ag could be lowered to be 1.72 × 10 −3 cm when the calcination temperature was 550 • C and hydrogen treatment was conducted in the Ar/H 2 (97/3) atmosphere at 500 • C and at a gauge pressure of 0.4 kg cm −2 . In addition, the optical transmittances of AZO thin films containing Ag nanoparticles were higher than 85% in the visible wavelength region. The decrease in transparency owing to the surface plasmon resonance of Ag nanoparticles was negligible.

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The non- and O-terminated diamond (1 1 1)-1  ×  1 surfaces, with the substitutional B (or N) dopants in different atomic layers, have been modelled in the present study. The influences of the O adsorbates, dopant and dopant position on the adsorption energy, have been studied by performing the density functional theory (DFT) calculations. Various parameters were additionally calculated in order to analyze the obtained results: bond lengths, total electron densities, bond populations, atomic charges, Fukui functions (FFs) and density-of-states. Dangling bonds on non-terminated surfaces, O adsorbates, as well as dopants within various atomic layers were all found to induce local effects. In fact, the degree of influences of the dopant on the adsorption energy of the O adsorbates, as well as on parameters like the near-surface bond lengths, total electron density, bond populations and atomic charges, were all found to be dependent on the dopant position. More generally, the deeper the dopant position, the less influence it had on the surface structures and properties. The influences by the dopant in the 1st or 2nd C atomic layer were observed to be significant, but those in the 3rd to 5th C layers were almost negligible. It was also found that the B dopant would decrease the adsorption energy of the adjacent O adsorbates, while the N dopant in the 2nd layer would increase it. Furthermore, the combination of the O adsorbates, together with the dopants within the 1st or 2nd C layer, could induce significant elongation of the bonds between neighboring atoms within the 1st and 2nd layers (i.e. C–C, C–B or C–N bonds). Moreover, all the terminating O atoms could react strongly with either the electrophilic or the nucleophilic species.