Solvothermal synthesis of PVP-assisted CuS structures for sunlight-driven photocatalytic degradation of organic dyes

Utilizing polymers in the synthesis process enhances the growth and variety of the semiconductor structures which increases their effectiveness in reducing environmental pollution. The ball-shaped CuS semiconductor structures were synthesized via solvothermal technique by varying the amount of PVP additive. The impact of PVP on the synthesis of CuS structures was investigated using XRD, FE-SEM, TEM, EDS, XPS, Raman, FT-IR, and UV–visible spectroscopic techniques. XRD analysis identified a polycrystalline hexagonal structure in the synthesized structures. FE-SEM revealed that these structures have spherical ball shapes containing flaky nanoparticles. EDS study reveals that PVP-assisted CuS structures are slightly copper-rich and have Cu:S (at.%) of 60:40. XPS analysis showed that in the synthesized material Cu element exists in two states i.e., Cu (II) and Cu(I). A broad absorption spectrum of CuS structures was observed within the 330–750 nm wavelength range with an absorption edge at ∼330 nm. Moreover, the photocatalytic degradation activity of PVP-assisted CuS against methylene blue and crystal violet organic dyes was investigated under natural sunlight conditions without any additive.