Embodiments of a coated substrate comprise a substrate (100) with a multi-functional multi-layer nanoparticle coating (105) having a thickness of up to about 500 nm thereon. The nanoparticle coating (105) comprises an ionic polyelectrolyte layer (110), and a mixed colloid layer disposed over the polyelectrolyte layer (110). The mixed colloid layer comprises hydrophilic colloid ions (130) and conductive colloid ions (120) which is coupled through electrostatic or non-electrostatic forces, and the conductive colloid ions (120), the hydrophilic colloid ions (130), or both are coupled to the polyelectrolyte layer (110).