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In this work, bismuth oxide nanoparticles were successfully deposited on porous silicon (PSi) in order to enhance the light absorption and reduce the optical losses. The obtained bismuth oxide $$(\hbox {Bi}_{2}\hbox {O}_{3})/\hbox {PSi}$$ samples were characterized by means of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, scanning electron microscopy (SEM) combined with energy-dispersive spectroscopy (EDS), atomic force microscopy (AFM), photoluminescence (PL), UV–visible absorption and reflection spectroscopy techniques. The XRD studies revealed the formation of the monoclinic $$\upalpha \hbox {-Bi}_{2}\hbox {O}_{3}$$ phase. The XPS analysis demonstrates the formation of highly pure $$\hbox {Bi}_{2}\hbox {O}_{3}$$ nanoparticles in accordance with XRD results. The SEM and AFM analyses confirmed that the bismuth oxide nanoparticles are well incorporated and uniformly distributed over the surface of PSi without changes in the arrangement and shape of the pores, resulting in an optimized microstructure. The $$\hbox {Bi}_{2}\hbox {O}_{3}/\hbox {PSi}$$ films showed better absorption than PSi layers as indicated by UV–Vis absorption technique. The reflection measurements confirmed a further reduction in reflectivity of PSi from 6.4 to 3.5% after the inclusion of $$\hbox {Bi}_{2}\hbox {O}_{3}$$ nanoparticles, which is of significant importance for solar cells application since it can enhance its conversion efficiency. The $$\hbox {Bi}_{2}\hbox {O}_{3}/\hbox {PSi}$$ films have a great promise to be used as efficient antireflection coatings in innovative concepts of higher efficiency and cost-effective solar cells.

Mn(II) doped SnO2 thin films used for shielding fluoride glasses against corrosion were investigated by x-ray absorption spectroscopy (EXAFS and XANE)S at the Sn and Mn K-edges. The effect of firing treatment on the densification of the films was studied. It has been evidenced a partial change of Mn valence from 2.3 to 2.6 upon heating which is attributed to a change of ratios of two Mn sites: grafted divalent Mn ions at the surface of SnO2 nanocrystallites and trivalent Mn ions embedded into a substitutional solid solution with Sn.

Cadmium poisoning and the cost of panel recovery which is very expensive and difficult in the buffer layers of CdS in solar cell, for these two drawbacks, we do a search on the effect of proportion of zinc/cadmium in the properties layers of CdS. For this, our studies study the properties of CdxZn1-xS layers deposited by chemical bath (CBD). CdZnS thin films were synthesized by chemical bath deposition (CBD) with different deposition protocols to optimize deposition parameters such as temperature, deposition time, ion concentrations and pH. The surface morphology, structural, optical and chemical properties of the CdZnS thin films were studied by SEM, XRD, Raman and UV-visible spectrophotometer. The transmittance is 80% in the visible region 300 nm - 800 nm; the crystalline structure is hexagonal and cubic, the grain size is between 9.95 to 25.82 nm. It is observed that the transmittance and the shape change with the concentration of zinc in the solution; this result favors the application of these films in solar cells application.