The invention relates to particles or a coating for splitting water. The aim of the invention is to provide particles or coatings for splitting water in which corrosive damage is prevented to a great extent. To achieve this, the particles or the coating consist(s) of a nucleus or a sub-layer and a shell or top layer, the nucleus or the sub-layer forming a reactive unit and consisting of a material that releases electrons with the input of energy from sunlight, said electrons being capable of splitting water into hydrogen and oxygen, and the shell or top layer forming a protective unit capable of holding the split products away from the surface of the reactive unit and having at the same time conductive fractions. Surprisingly, corrosive damage to the reactive particles is prevented to a great extent by the targeted separation of reaction particles and split products over the range of the released electrons.