Seed-assisted Method Research Articles

Layer-by-layer assembly synthesis of ZnO/SnO 2 composite nanowire arrays as high-performance anode for lithium-ion batteries

A layer-by-layer approach has been developed to synthesize ZnO/SnO 2 composite nanowire arrays on copper substrate. ZnO nanowire arrays have been first prepared on copper substrate through seed-assisted method, and then, the surface of ZnO nanowires have been modified by the polyelectrolyte. After oxidation–reduction reaction, SnO 2 layer has been deposited onto the surface of ZnO nanowires. The as-synthesized ZnO/SnO 2 composite nanowire arrays have been applied as anode for lithium-ion batteries, which show high reversible capacity and good cycling stability compared to pure ZnO nanowire arrays and SnO 2 nanoparticles. It is believed that the improved performance may be attributed to the high capacity of SnO 2 and the good cycling stability of the array structure on current collector.

Experimental Evidence for Nucleation and Growth Mechanism of Diamond by Seed-Assisted Method at High Pressure and High Temperature

In this paper, the diamond growth mechanism at high-pressure and high-temperature (HPHT) conditions from solvent-graphite system was investigated by growing diamond on different seeds and tracking the particular shapes of the seeds before and after treated under HPHT conditions. According to the results, we established a direct correlation between the morphology of the diamond and the original shape of the seeds. The crystallization of carbon phases (diamond-graphite) in the Fe−Ni−C system is depicted in detail in the P−T diagram. Experimental results show the synthetic pressure obviously decreases when diamond seed crystals are added into the original synthetic system, which confirms that the energy barrier of the diamond nucleation is higher than that of growth. In addition, we detected in our experiments that the diamond growth at HPHT conditions belongs to two-dimensional growth. Furthermore, we also found crystal direction and original shape of seed play important roles in the formation of diamond mo...