Switching surface interactions with photochemical and electrochemical control

Surfaces are the barrier between two states of matter, most recognisably a solid in contact with either a gas (air) or a liquid. Surfaces that can change their interaction with the other state of matter would have widespread importance and potential in many applications and systems. The interactions of surfaces with liquids are especially important ranging from biofilm formation, corrosion protection, to how fast a boat moves through water. The interaction of concern in this thesis is that between smart surfaces and liquids, and especially liquid crystals. The properties of surfaces relevant to interactions with liquid crystals are described and the design strategies to make these surfaces are categorised by the stimuli they respond to are discussed. In many applications of liquid crystals, the interactions of the surface are controlled through a so called alignment layer, which largely determines the phase adopted by the liquid crystal. Controlling liquid crystalline states by changing the interactions of the surface alignment layer with the liquid crystal is the ultimate goal of the work descried in this thesis. The surfaces and coatings described not only fulfill multiple functions, but also change their functionality upon an external stimulus, with the ultimate goal to control liquid crystalline phases.