Department of Physics, Institute of Advanced Materials (IAM), Hong Kong Baptist University (HKBU), 224 Waterloo Road, Kowloon Tong, Hong Kong SAR, People's Republic of China.
Nanoscale. 2012 Sep 28;4(19):5835-9. doi: 10.1039/c2nr31680c. Epub 2012 Aug 16.
Metal-assisted chemical etching (MACE) was carried out to fabricate solid silicon nanowires (s-SiNWs) and mesoporous silicon nanowires (mp-SiNWs). Total reflection and transmission were measured using an integrated sphere to study optical properties of the MACE-generated silicon nanostructures. Without NW aggregation, mp-SiNWs vertically standing on a mesoporous silicon layer trap less light than s-SiNWs over a wavelength range of 400-800 nm, owing to porosification-enhanced optical scattering from the rough inner surfaces of the mesoporous silicon skeletons. Porosification substantially weakens the NW mechanical strength; hence the elongated mp-SiNWs aggregate after 30 min etching and deteriorate optical trapping.
采用金属辅助化学刻蚀（MACE）工艺制备了体硅纳米线（s-SiNWs）和介孔硅纳米线（mp-SiNWs）。利用积分球对全反射和全透射进行了测量，以研究 MACE 生成的硅纳米结构的光学性质。在没有纳米线聚集的情况下，介孔硅层上垂直排列的 mp-SiNWs 在 400-800nm 的波长范围内比 s-SiNWs 捕获的光少，这是由于粗糙的介孔硅骨架内表面增强了多孔硅的光学散射。多孔化显著削弱了纳米线的机械强度；因此，在 30 分钟刻蚀后，细长的 mp-SiNWs 会聚集，从而降低光捕获效率。
