Silicon, macroporous nanoporous

In the majority of cases nanoporous materials exist in a highly dispersed state (seldom - as films). It limits practical application of these materials and in many cases makes difficult for study of their properties. Samples of the nanoporous carbon (NPC) used in this work are produced as a body of cylinder shape with a sufficient mechanical strength. They synthesized by heat treatment of carbide silicon and carbide titanium in chlorine have been studied in the present work. The samples of materials are characterized by the advanced structure of pores, which contains two types of pores macropores (with the sizes in a few micron) and nanopores with sizes about 0.8 nm. Surface area and volume of pores NPC with... 

Luminescence from Porous Electrodes As in bulk systems, photogeneration of charge carriers in a porous electrode or injection of minority carriers from solution can lead to light emission [25]. In a macroporous system in which the depletion layer can follow the contours of the porous matrix, one does not expect significant differences between bulk and porous electrodes with regard to the potential dependence of the emission. If, however, the porosity is high and the dimensions of the structures become very small (e.g. <5 nm) then special effects may be expected. These are indeed found as, for example, with nanoporous silicon. 

When the silicon-electrolyte interface is front-side illuminated during the anodization, the macropore Si walls and the top of the Si pillars are covered by a nanoporous silicon layer (Fig. 13) [70, 91, 92, 99, 105, 106]. Cross-sections of elec-trochemically detached nanoporous layers well illustrate the morphology of the... 

To prepare porous silicon microarrays in the Laurell group, 380 pm-thick <100> silicon wafers were utilized. The p-type boron-doped wafer with a resistivity of 10-15 Qcm was mounted in an in-house-made electrochemical etch cell. The porosification was made in an electrolyte solution of HF/DMF 1 10, and the wafer was illuminated by a 100 W halogen lamp at a distance of 10 cm. A current density of 2 mA/cm was applied for 1 h. The macropores in the porous layer produced for protein microarrays typically measured 0.5-1.5 pm with a fine side branching network of nanopores (Ressine et al. 2005). 

Other recent materials created using these ordered arrays include porous nickel phosphide film for lithium ion batteries, porous aluminum films for lithium electrodeposition, macroporous silicon films for optics, cobalt metal nanoarrays of various morphologies for biomedicine," macro-/ nanoporous gold films for electrocatalysis, " silver bowls as SERS substrates, and complex macroporous gold and polypyrrole films. ... 

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