ASSEMBLY OF ORIENTED NANOMETER CHANNELS ON ORGANIC LAYERS

摘要

Strategies for the assembly of molecular sieve crystals on gold substrates are discussed. The article focuses on the growth of oriented nanometer structures on organic layers. Three different models of self-assembled multilayer mixed organo-phosphonate films are prepared on gold surfaces. The first model uses spacer molecules having a chain length similar to the phosphonate chains but containing methyl head groups. In model II, the phosphonate surface acts as a base layer, and a longer alkyl spacer molecule protrudes from the surface. The third model system contains a mixture of end groups such as bromide and methyl with different chain length and ratios. The bromide end groups in the mixed layers were converted into organic templating agents similar to those used in the preparation of the bulk synthesis gel. The first two types of mixed functional films show profound effects on the surface crystallization of zincophosphate molecular sieves, with a nonlinear dependence of both surface crystal density and orientation on phosphonate surface group density.