Our research aims to develop plastic films that change the colour of the light that passes through them, not by absorbing certain wavelengths of light, as a simple colour filter would, but by converting light of one wavelength to another without losing any energy. Such a film, applied to a silicon solar cell, could make it up to 30% more efficient. To do this we need to make semiconductor nanocrystals ("quantum dots"), coat them with a very thin layer of an organic semiconductor so the two materials are in molecular contact. This proposal is about how we prepare the surfaces of the quantum dots to make sure the desired molecules will definitely stick there. What we are designing will only work if the thin layer of organic semiconductor is intimately stuck on to the quantum dot, so that the light can transfer seamlessly from one to the other.