Interface engineering of Ti-MOFs: Adsorption of anionic, cationic and neutral dyes in wastewater

Adsorption technology is a promising method of removing pollutants in fluid phase. Ti-MOFs are widely used as adsorbents. But Ti-MOF with different morphologies for dyes adsorption has not been reported, so far. In this work, three kinds of morphologies Ti-MOFs, truncated octahedron, frustum, cake-like structure were prepared to adsorbing different dyes, including methylene blue (MB), methyl orange (MO) and indigo (IB), and it found that has the best removal efficiency for the cationic MB dye. It is found the adsorption process is exothermically and follows pseudo-second-order/Freundlich isotherm model. Adsorption is facet-dependent, absorbed energy has the order of {100}> {111}> {001}, truncated octahedron Ti-MOFs is with the large exposed {111}/{100} surface, exhibit the best adsorption and three kinds of Ti-MOFs have the adsorption order of truncated octahedron > frustum structure > cake-like structure. Actual wastewater treatment was processed. This work provided a highly efficiently adsorbent for industrial dyes wastewater remediation.