| 摘要 |
<p>The invention relates to novel and improved methods for preparing porous silicon and for modifying the structural and/or optical properties of silicon. Generally, the invention relates to a method for modifying the structural properties of silicon, in particular non-porous silicon, by ultrasonication in the presence of a liquid HF- free medium wherein said structural properties are selected from the group consisting of roughness, porosity, crystallinity, number of defect states, hydrogen-terminated bonds, quantum dots, and centers for charge separation. In more specific embodiments, the ultrasonication is effected in a liquid medium comprising a solvent which is selected from the group consisting of an organic solvent, including an alcohol, water, an ionic liquid or a mixture thereof. Preferably, the liquid medium for ultrasonication further contains an additive which is selected from the group consisting of hydrogen, a hydrogen donor, e.g. NaBH4, Mg or Al, a charged or uncharged surfactant, a polyelectrolyte, a complexation agent comprising an element E, with E = N, O, F, H, or mixtures thereof.</p> |
