Advanced Aqueous Solutions for Low Voltage and Electrolysis-Free Electrowetting Devices

Electrowetting has come a long way since the concept was first introduced by Gabriel Lippmann in 1875.Since the emergence of Bruno Berge's concept of electrowetting on dielectrics in the 1990's, electrowetting has seen an explosion of interest.Recent development in electrowetting applications has led to the need for low operating voltages for many applications.Besides a low voltage requirement, larger contact angle modulation, reliable, and electrolysis free electrowetting are important for all electrowetting applications.The basis of this thesis is to compare and introduce ways to attain low voltage electrowetting on a two-layer dielectric system.Two dielectrics are investigated, Al 2 O 3 and Si 3 N 4 .Surfactants are then tested in the form of sodium dodecyl sulfate (water soluble) and triton X-15 (oil soluble) to observe how the interfacial surface tension affects electrowetting effect.Once low voltage electrowetting is observed, the investigation of electrolysis free and reliable electrowetting is discussed.Various surfactants are tested for dielectric failure and a catanionic surfactant is synthesized.The catanionic surfactant is also tested for dielectric failure.Once those tests are performed, water is replaced as a medium for electrowetting by propylene glycol.With larger molecules for propylene glycol, dielectric failure is substantially reduced.The results of the work described herein show the promise for low voltage and reliable electrowetting.