Optical study of ZnP2 nanoparticles in zeolite Na-X

Nanoparticles of the II-V semiconductor (ZnP2) were prepared and investigated. ZnP2 nanoparticles were incorporated into zeolite Na-X matrix. Absorption, diffuse reflection (DR) and photoluminescence (PL) spectra of ZnP2 nanoparticles were measured at the temperature of 77 K. Five bands B1-B5 are observed in both the DR and PL spectra demonstrating the blue shift from the line of free exciton in bulk crystal. We attribute the B1-B5 bands to five stable nanoparticles with size less than the size of zeolite Na-X supercage. We observed Stokes shift of the PL bands with respect to the absorption bands. This dependence of this Stokes shift on the particle size is nonmonotonic.