Method of preparing light scattering layer

A method of preparing a light scattering layer, the method comprising:

• obtaining an emulsion by dispersing droplets of a second phase into a first phase comprising a hydrophobic metal oxide sol, the second phase comprising a droplet supporting material and a hydrophilic liquid;
• forming an emulsion layer by casting the emulsion on a substrate;
• converting the emulsion layer into a matrix precursor layer by baking the emulsion layer and thus solidifying the first phase, the matrix precursor layer comprising a plurality of voids derived from the droplets of the second phase;
• and
• converting the matrix precursor layer into a metal oxide matrix layer by calcining the matrix precursor layer, the metal oxide matrix layer comprising a plurality of voids derived from the droplets of the second phase.