Photocatalysis is a green technology which converts abundantly available photonic energy into useful chemical energy.

Various new strategies have been recently developed to produce CaCO ₃ micro-/nanoparticles with controlled size, morphology, polymorphism and crystallinity, which are then surface modified, functionalized and hierarchically assembled to yield medical, environmental, and energy materials.

Hybrids of silver particles of 1 to 2 nm in size with highly branched amphiphilically modified polyethyleneimines adhere effectively to polar substrates providing environmentally friendly antimicrobial coatings.