Sun-light-driven plasmonic Ag/AgCl@TNT photocatalysts for high-efficient absorption-regeneration and photocatalytic degradation

Abstract

Sun-light-driven plasmonic photocatalyst Ag/AgCl@TNT was successively synthesized by two-step hydrothermal method and followed by a photo-reduction procedure. The Ag/AgCl@TNT composites performed great adsorption and regeneration properties to high chroma dyes via coupling with the photo-degradation technique. The adsorption capacity for crystal violet (CV) solution after five cycle regeneration texts was found to be 115 mg.g−1 (reduced by 8%), which was much higher than the bare H2Ti3O7 nanotube (TNT) (27 mg.g−1), as it almost showed no renewable adsorption ability under the same condition. The excellent performance was attributed to the synergistic effect of the Ag/AgCl nanoparticles (NPs) and TNT, the TNT provided the absorption behavior with large and negatively charged surface, whereas the exposed Ag/AgCl NPs may easily get excited under sun light due to the SPR effect and charge separation mechanism. Once the excited electrons transferred to TNT, the compensative electrons may transfer from AgCl to Ag simultaneously and leave the Cl0 there in turn, thus the Ag/AgCl@TNT can exhibit a great cycle stability not only on the high chroma dyes removal but also the phenol degradation and Cr (VI) reduction, of which the removal rate were both over 95% in dozens of minutes. The TOC results verified the progressive mineralization of phenol resulting from the effective decomposition of aromatic intermediates, which indicated the great potential for practical applications in environmental remediation.