pubs.acs.org/Langmuir © 2010 American Chemical Society
Self-Cleaning Antireflective Coatings Assembled from Peculiar Mesoporous Silica Nanoparticles Xiaoyu Li,†,‡ Xin Du,†,‡ and Junhui He*,† †
Functional Nanomaterials Laboratory and Key Laboratory of Organic Optoelectronic Functional Materials, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (CAS), Zhongguancun Beiyitiao 2, Haidianqu, Beijing 100190, China, and ‡Graduate University of Chinese Academy of Sciences, Beijing 100864, China Received April 27, 2010. Revised Manuscript Received July 1, 2010 Novel mesoporous silica nanoparticles of peculiar shapes were synthesized, from which hierarchically porous silica coatings were fabricated on glass substrates via layer-by-layer (LbL) assembly, followed by calcination. These porous silica coatings were highly transparent and superhydrophilic. The maximum transmittance reached as high as 94%, whereas that of the glass substrate is 91%. The time for a droplet to spread lower than 5° decreased to as short as 0.25 s. After the coating surface was treated with a low surface energy material, the surface became superhydrophobic (water contract angle >150°) with a very low sliding angle of
