Preparation, Surface Modification, and Photoelectrochemical Application of Silicon Nanowires
| Autor: | Wirawan Ciptonugroho, 席維倫 |
|---|---|
| Rok vydání: | 2009 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 97 Single crystalline silicon nanowires have been synthesized using electroless metal deposition method on a p-type silicon wafer (100) in AgNO3/HF solutions. The orthogonal structure has been confirmed by SEM. XRD analysis exhibits one highly dominant peak at 700 which is belong to (004) silicon plane. UV-VIS spectra show the reflectance of light is significantly reduced to less than 10% for at least 30 minute immersion time. Surface modification of silicon nanowires with platinum nanoparticles has also been carried out by ethylene glycol reduction and electroless plating method. The platinum nanoparticles deposit very well and uniformly dispersed on silicon nanowires for the electroless plating method at which the particle size is 5.99 nm in average and 2.295 nm of standard deviation. From HRTEM image, 1.388 Å of lattice spacing has been obtained which is in the accordance with platinum (220) plane. EDX spectra also corroborate the presence of platinum nanoparticles. In contraty, only a few platinum nanoparticles remain on silicon nanowires surface by ethylene glycol method and electroless deposition in which ethylene glycol was employed as solvent. Photoelectrochemical measurement was carried out to examine the effect of platinum-modified silicon nanowires by irradiating the samples using 97.1 mW/cm2 of light power (measured at 400 nm). The nanowires structure has the greater photocurrent compared to the unmodified planar silicon. Subsequently, platinum-modified silicon nanowires perform the highest photocurrent over all tested sample. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
| Externí odkaz: |
|