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This study synthesized cuprous oxide nanoparticles (Cu2O-ONPs) from the green precursors CuSO4.3H2O and Na2SO3. The materials samples were studied at prepared temperatures of 70 °C, 80 °C, 90 °C and 100 °C. The structure and characteristics of the materials were determined by methods such as Raman shift, UV-vis absorption spectrum, SEM, XRD. The results showed that, Cu2O-ONPs were crystallized the best in octahedral form at temperature of 90 °C. The absorption spectrum of the materials was in the visible light region \(\lambda \,\, \approx\) 500–600 nm with the band gap energy defined as Eg \(\approx\) 1.78–2.1eV. At calcination temperatures of 200 °C the materials retained the octahedral shape, but the absorption spectrum was shifted strongly in visible light region \(\lambda \,\, \approx\) 600–700 nm with Eg \(\approx\) 1.94eV. At the firing temperature of 300–400 °C the octahedral shapes of the materials were slightly distorted. At 500 °C the materials particles were inflated, broken and no longer retaining the original octahedral shape. Within this high temperature range of 300–500 °C the absorption spectra of the materials samples were shifted more strongly in visible light region \(\lambda \,\, \approx\) 800–900 nm, the optical band gap energy was reduced to a value Eg \(\approx\) 1.37–1.46eV which was due to the existence of two Cu2O-CuO phases. These will be desirable of material fabrication for applications in photochemical reactions in visible light region and other specific commercial applications that need further research and exploitation.

Antimony-doped tin oxide (ATO) nanoparticles (NPs) (Sb-doped content 3%, 10%, and 15%) were synthesized by the (2 l autoclave, medium-scale) solvothermal method followed by sintering at various temperatures (500°C, 800°C, 900°C and 1000°C) so they would crystallize. The particle size increased from several to tens of nanometers with the increase of sintered temperature from 500°C to 1000°C, sharply from 800°C to 1000 °C; ~30 g of final product was received for each experiment. More interestingly, the crystallinity of the as-synthesized ATO was also increased with the increasing Sb doped content from 3% to 15%. The ATO NPs were coated onto glass substrates and then sintered at 500°C, which effectively prevented transmittance of infrared (IR) wavelengths (>800 nm) with 10% wt Sb-doped content, which is useful for thermal insulated glass coating application.

Undoped and Eu3+ doped ZnO nanostructures were prepared by single-step mild hydrothermal conditions. The nanostructures were deposited on a Si or glass substrate without template. The reaction was carried out for 10–20h which resulted in morphology and aspect ration of the final products depend on the concentration of the precursors and reaction time. The concentration of dopant Eu3+ in the synthesized nanostructures was below 4 at.%. The crystal structure and the microstructure of the doped nanostructures were studied and compared with undoped ZnO. Photoluminescence measurements of the nanowires exhibit a strong band gap emission at room temperature. In partcular, relative intensity of band gap and defect emission changes drastically in ZnO:Eu and ZnO nanostructures with different morphology. The highly crystalline ZnO nanorods, nanowires can be a good one-dimensional candidate to study optical and electronic properties