Controlled chemical transformation and crystallization design for the formation of multifunctional Cu-doped ZnO/ZnAl2O4 composites

Photoactive Cu-doped ZnO-ZnAl 2 O 4 ceramic nanocomposites and coatings were prepared by polymer-salt method. The luminescent and IR spectroscopy, SEM and XRD methods were used for the study the structure, morphology and materials properties. The nanocomposites consist of small hexagonal ZnO and cubic ZnAl 2 O 4 nanocrystals having size about 10 nm. The study of luminescence properties shows that prepared nanocomposites can be used as light down-converters that transfer UV-C radiation into UV-A and visible spectral range. These nanocomposites can be very attractive in photovoltaic applications as spectral down-converters. Also obtained nanocomposites demonstrate the ability to generate chemically active singlet oxygen under UV-A radiation and blue light. The experiments show that Cu-doped ZnO-ZnAl 2 O 4 materials demonstrate antibacterial activity against gram-positive bacteria.