Sun-light driven photo degradation of organic dyes from wastewater on precipitation Ag2CrO4 over SiO2-aerogel and nano silica.

In this research, The Ag 2 CrO 4 over Silica Aerogel and Nano Silica was successfully synthesized using the precipitation method, which was used to obtain an appropriate morphology and used ultrasound to better particle distribution on Silica Aerogel and Nano Silica. To determine the physicochemical and optical properties of the synthesized samples, the characterization techniques such as XRD, FESEM, FTIR, BET-BJH, and UV–Vis DRS were employed. Photocatalytic experiments show that Ag 2 CrO 4 /NS(20%) has the highest solar-light-driven degradation of Acid Orange 7 (95.4% in 120 min). The best photo activity of Ag 2 CrO 4 /NS(20) is ascribed to efficient homogenous distribution of Ag 2 CrO 4 nanoparticles on the Nano Silica and Silica Aerogel, high surface area, and remarkable separation of charge carries and low recombination rate of electron-hole pairs due to the unique structure of Nano Silica. Also in this study Silica was synthesized by CO 2 reduction method to investigate the impact of surface area on photocatalyst performance of optimal sample (Ag 2 CrO 4 /NS(20)). As can be seen from FESEM images by adding Nano Silica more than 20%, agglomeration occurs. This agglomeration impedes Ag 2 CrO 4 Nano particles to adsorb light. [Display omitted] • Successfully synthesis Ag 2 CrO 4 over SiO 2 -Aerogel and Nano Silica by precipitation method. • Increase specific surface area of Ag 2 CrO 4 by applying Silica Aerogel and Nano Silica. • Optimum percentage of Nano Silica is 20%, more than this amount it cause to agglomeration on the surface of Photocatalyst. • Applying Nano Silica cause to reduce particle size and increase light adsorption on the surface of catalyst. In this study, Ag 2 CrO 4 /SiO 2 nanostructure was synthesized by the precipitation method to ameliorate the low specific surface area of Ag 2 CrO 4 with nano-Silica (NS) and Silica Aerogel (SA). The coupled nanophotocatalysts with various weighted contents of Ag 2 CrO 4 and Nano Silica were characterized with PXRD, FESEM, UV–Vis, FTIR and BET-BJH analyses. In order to find the optimal amount, different percentages of Nano Silica 10%, 20% and 30% were investigated. It was observed from BET-BJH that adding Nano Silica lead to an increase the catalyst surface area and crystallinity of synthesis samples. Then, in order to investigate the impact of specific surface area on optimal catalyst activity (Ag 2 CrO 4 /Nano Silica (20%)), Silica Aerogel, which has a higher surface area than Nano silica, was used instead of Nano silica. It was observed that increasing the surface area has a direct effect on the activity of the Ag 2 CrO 4. The photocatalytic activity of various nanocomposites was evaluated in the remediation of the organic dyes after 120 min visible light irradiation. The tremendous enhanced photocatalytic activity under the simulated solar light with 95.4% removal of AO7 was observed over Ag 2 CrO 4 /Nano Silica (20%) sample. In addition, to illustrate how the influence of various parameters such as various organic dyes, pH, catalyst loading and reusability on the photodegradation efficiency, were conducted over Ag 2 CrO 4 /Nano Silica (20). The high activity was obtained in the medium with pH = 7, catalyst loading = 1 g/L and AO7 concentration = 20 mg/L. [ABSTRACT FROM AUTHOR]