Enhanced adsorption and photocatalytic degradation of high-concentration methylene blue on Ag2O-modified TiO2-based nanosheet

TiO2-based nanosheet (TNS) was modified with Ag2O, and the adsorption and photocatalytic performances of modified nanosheet were characterized by the removal of high-concentration methylene blue (MB). When TNS was loaded with a proper amount of Ag2O, the adsorption capacity is enhanced to 2.2 times, with a maximum of 172.4 mg/g determined from Langmuir isotherm. The adsorption results also show that a small amount of Ag2O-modified TNS can quickly enrich large amounts of MB molecules onto its surface via adsorption. Furthermore, Ag2O-modified TNS exhibits novel separation efficiency of photogenerated carriers evidenced by photoluminescence measurements, and enhanced photocatalytic activity proved by the degradation of MB. The good reusability of Ag2O-modified TNS implies a potential application for dealing with high-concentration dyes by adsorption–photocatalytic degradation.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► TiO2-based nanosheet (TNS) was modified by Ag2O photocatalyst. ► Ag2O-modified TNS possesses enhanced adsorption and photocatalytic activity. ► The maximum adsorption capacity of Ag2O-modified TNS for MB is up to 172.4 mg/g. ► High-concentration MB can be removed by adsorption–photocatalytic degradation. ► Ag2O-modified TNS exhibits good reusability for removing high-concentration MB.