Thermally Induced Silane Dehydrocoupling on Silicon Nanostructures

Organic trihydridosilanes can be grafted to hydrogen‐terminated porous Si nanostructures with no catalyst. The reaction proceeds efficiently at 80 °C, and it shows little sensitivity to air or water impurities. The modified surfaces are stable to corrosive aqueous solutions and common organic solvents. Octadecylsilane H(3)Si(CH(2))(17)CH(3), and functional silanes H(3)Si(CH(2))(11)Br, H(3)Si(CH(2))(9)CH=CH(2), and H(3)Si(CH(2))(2)(CF(2))(5)CF(3) are readily grafted. When performed on a mesoporous Si wafer, the perfluoro reagent yields a superhydrophobic surface (contact angle 151°). The bromo‐derivative is converted to azide, amine, or alkyne functional surfaces via standard transformations, and the utility of the method is demonstrated by loading of the antibiotic ciprofloxaxin (35 % by mass). When intrinsically photoluminescent porous Si films or nanoparticles are used, photoluminescence is retained in the grafted products, indicating that the chemistry does not introduce substantial nonradiative surface traps.