Rapid microwave-assisted deposition of microwire patterns of nanoaluminum and nanosilver from colloids.

The rapid self-assembly of microwire patterns of 52-nm aluminum and 19-nm silver nanoparticles was demonstrated under microwave heating using novel surfactant-solvent systems. Colloid solutions of 0.03% (w/v) nanoaluminum in 10% (v/v) poly(dimethylsiloxane)-acetone were used to self-assemble the microwire patterns of Al on glass substrates, which were dipped into the solution and held against the wall. Also, colloids of 0.001% (w/v) nanosilver prepared in an acetone solution of 33.3% (v/v) chloroform, 16.6% (v/v) poly(dimethylsiloxane), and 0.3% (v/v) Tween-20 were utilized for the deposition of microwire patterns under microwave heating at 51-55 degrees C. The evaporation-induced self-assembly of microwire patterns at the contact line was due to stick-slip dynamics. The rapid self-assembly of micropatterns of nanoaluminum and nanosilver was also demonstrated under microwave radiation within 2 min, and the width of the microwires was about 1-20 mum depending on the concentration of nanoparticles.