Resumen
The invention relates to the use, in the production of materials or devices for photonic applications, of chalcogenide-type compounds having an octaedrically co-ordinated indium element, and in which a transition element is introduced in the octaedric position, thus generating a partially occupied intermediate band separate from those of valency and conduction of the initial semiconductor, according to quantum mechanics calculations. This enables, by absorption of two photons having lower energy than the width of the prohibited band of the initial semiconductor, a result equivalent to that obtained, without the intermediate band, by the absorption of a higher-energy photon. The use of such a material can thereby improve efficiency and performance in various photovoltaic, photocatalytic, photoelectrochemical, optoelectronic or photonic conversion devices. Indium sulfide substituted in part with vanadium or titanium is one of the specific materials having these properties that is synthesised according to the invention.