ultrasound-assisted design of narrow-band gap ag/ag2cro4 vs# ceo2 nanophotocatalyst for remediation of rhb and ao7 under sunlight

In this research, the visible-light-active ag2cro4 as narrow-band gap nanophotocatalyst was synthesized by a sono-precipitation method and ceo2 as wide-bandgap nanophotocatalyst was synthesized by the alkaline hydrothermal and their performance was compared in the degradation of 25 mg/l acid orange 7 (ao7) and 10 mg/l rhodamine b (rhb)# the mentioned nanophotocatalyts were characterized by xrd and fesem analyses# the consequences obtained from xrd demonstrated that the samples were fabricated well# moreover, the results of reactor tests exhibited that with 1 g/l catalyst and after 120 min simulated sunlight irradiation, the degradation percentage of ao7 and rhb over the ag2cro4 was 97 and 99#5%, respectively# in contrast, the efficiency obtained over the ceo2 for the degradation of ao7 and rhb in the same conditions was 10#9 and 14#3%# the high activity of the ag2cro4 nanophotocatalyst could be devoted to its suitable bandgap, high activity in the solar light region originating from the high absorption light, which could lead to the increase of excitons (electron-hole pairs), the effect of ultrasound energy and the plasmonic effect of ag particles#