Photoinduced generation of electron anions in H-doped nanoporous oxide 12CaO∙7Al2O3: Toward an optically controlled formation of electrides

We suggest, on the basis of detailed ab initio calculations of both ground and photoexcited states of H-doped 12CaO∙7Al2O3 (C12A7:H), that stable high-conductivity regions can be optically generated in this insulating system. Each H− ion in C12A7:H can, under photoirradiation at 3.8–4.5 eV, produce up to two electrons and a proton that binds to the lattice network and forms OH−. Mobile electrons play a role of anions in this system. They move over subnanosized cages of the C12A7 lattice via polaron hopping. The insulating state is reversibly restored upon heating to 300 °C.