The hydrothermal approach was used to make an inorganic semiconducting CdS/Zn3(PO4)2
nanocomposite at a mild reaction temperature of 100 ºC. The XRD data indicate peaks that correspond
to CdS hexagonal structure and Zn3(PO4)2 monoclinic-phase with good crystalline character.
Surprisingly, the phase shift from α-phase of Zn3(PO4)2 to γ-phase of Zn3(PO4)2 is observed under
hydrothermal conditions due to the coupling of CdS with Zn3(PO4)2, as well as internal structural
alterations leading to the formation of CdS/Zn3(PO4)2 nanocomposite. Debye-Scherrer and W-H methods
were used to calculate average crystallite size, lattice strain and dislocation density. The average crystal
lattice is 15-25 nm in size. The hexagonal spheres aggregated on rectangular flakes, indicating core-shell
heterostructure, may be seen on the surface morphology of the prepared composite. Due to the quantum
size effect, the absorption peak for the composite is in the visible wavelength. It also has a low optical
band gap of 2.42 eV, which makes it useful for photocatalytic and photoelectrochemical applications.
FT-IR spectrum shows all the fundamental vibrational modes of CdS/Zn3(PO4)2 nanocomposite. Colour
coordinate values and CCT values of the prepared composites indicate that they are used for LED
applications and the photoluminescence spectrum reveals a broad, intense luminescence band in the
visible region with wavelengths ranging from 510 to 518 nm, in good agreement with the absorption
wavelength and the CIE diagram.