Fabrication of Ag-TiO2 functionalized activated carbon for dyes degradation based on tea residues

Being used as a renewable resource material, waste tea residues are usually applied in pollutants adsorption. However, it is a big challenge to effectively adsorb and degrade the pollutants at the same time in water resources. Herein, we proposed a strategy to prepare green tea residue derived activated carbon (g-AC), which was further used as substrates for loading Ag-TiO2 nanoparticles, forming a complex of Ag-TiO2/g-AC, to adsorb and degrade the dyes in wastewater. The study showed that Ag-TiO2/g-AC complexes behaved an excellent adsorption capacity of 479.5 mg g(-1) and a high degradation efficiency of 95.9%. Also, the reusability of Ag-TiO2/g-AC in multiple cycles (n = 4, > 82.9%) revealed its good stability in the degradation process. This work, therefore, provides an alternative to recycle the tea industry-based wastes, offering a waste-to-green method for adsorbing and removing the pollutants in water.